FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
“CHARGE AND DISCHARGE CONTROL DEVICE, CHARGE CONTROL METHOD,DISCHARGE CONTROL METHOD, AND
PROGRAM”
MITSUBISHI HEAVY INDUSTRIES, LTD., a Japanese
Company of 16-5, Konan 2-chome, Minato-ku, Tokyo, 108-
8215, Japan
The following specification particularly describes the invention and the
manner in which it is to be performed.
EN Translation of Original JP Specification
1
DESCRIPTION
CHARGE AND DISCHARGE CONTROL DEVICE, CHARGE CONTROL METHOD,
DISCHARGE CONTROL METHOD, AND PROGRAM
TECHNICAL FIELD
[0001]
The present invention relates to a charge and discharge control device, a charge
control method, a discharge control method, and a program for controlling charge and
discharge of a secondary battery to be coupled to a load capable of generating the
regenerative power.
Priority is claimed on Japanese Patent Application No. 2011-269937, filed
December 9, 2011, the content of which is incorporated herein by reference.
BACKGROUND ART
[0002]
Conventionally, vehicles running with the power supplied from wires are known.
The power required for such a vehicle to run (running power) differs depending on
environments, such as slopes of rails on which the vehicle runs. For this reason, the
capacity and power consumption of a substation supplying the power to wires are
determined based on a variation of the voltage caused by the running power.
[0003]
Additionally, when such a vehicle brakes and thereby causes the regenerative
power to be generated, the regenerative power is fed to the wires to prevent a
regenerative failure. The regenerative power fed to the wires is collected by the
EN Translation of Original JP Specification
2
substation. For this reason, an interval at which substations are to be installed is
determined based on a variation of the voltage caused by the regenerative power.
[0004]
In order to reduce costs for a traffic system by decreasing the number of
substations to be installed, suppression of the peaks of the running power and the
regenerative power (peak cut) has been considered. As a method of cutting the peaks of
the running power and the regenerative power, there is a method in which a secondary
battery is mounted on a vehicle to absorb the regenerative power and supplement the
running power.
In order to adequately cut the peak of the power, it is necessary to adequately
manage a charging rate of the secondary battery.
[0005]
Patent Document 1 discloses a method of performing a charge so that a charging
rate varies within an adequate range of the charging rate, thereby preventing a secondary
battery mounted on a wire-less vehicle from deteriorating.
Patent Document 2 discloses a method of controlling a charging rate of a
secondary battery mounted on a wire-less vehicle.
CITATION LIST
[Patent Document]
[0006]
[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-054958
[Patent Document 2] Japanese Patent Laid-Open Publication No. 2009-273198
DISCLOSURE OF THE INVENTION
EN Translation of Original JP Specification
3
Problems to be Solved by the Invention
[0007]
However, the methods disclosed by Patent Documents 1 and 2 are used to adjust
the charging rate of the secondary battery in order to enable the vehicle to run in
wire-less intervals. Both documents fail to disclose a method of adjusting the charging
rate of the secondary battery while performing a peak cutting process.
An object of the present invention is to provide a charge and discharge control
device, a charge control method, a discharge control method, and a program for adjusting
a charging rate of a secondary battery while performing a peak cutting process.
Means for Solving the Problems
[0008]
The present invention has been made to solve the above problem. The present
invention is a charge and discharge control device configured to control charge and
discharge of a secondary battery coupled to a load capable of generating a regenerative
power. The charge and discharge control device includes a peak cutting unit configured
to, in a case that a required power required by the load is larger than or equal to a
reception peak-cut power set as a power receivable from a wire, have the secondary
battery discharged at a power rate that is larger or equal to a difference between the
required power and the reception peak-cut power; an improving power value calculating
unit configured to calculate a discharge improving power value defined as a power value
that increases as a charging rate of the secondary battery becomes larger than a target
charging rate; and a charging rate improving unit configured to, in a case that the
required power is smaller than or equal to the reception peak-cut power, have the
secondary battery discharged at a power rate that is smaller than or equal to the discharge
EN Translation of Original JP Specification
4
improving power value calculated by the improving power value calculating unit.
[0009]
Additionally, regarding the present invention, the peak cutting unit is preferably
configured to have the secondary battery discharged at a power rate equal to the
discharge improving power value, in a case that the required power is larger than or equal
to the reception peak-cut power, and the discharge improving power value is larger than
or equal to a value of a difference between the required power and the reception peak-cut
power.
[0010]
Further, regarding the present invention, the peak cutting unit is preferably
configured to have the secondary battery discharged at a power rate that is smaller than a
maximum discharge power value for discharge allowed by the secondary battery.
[0011]
Moreover, regarding the present invention, the charge and discharge control
device preferably further includes a discharge terminating unit configured to terminate
discharge by the peak cutting unit in a case that the charging rate of the secondary battery
is smaller than a minimum charging rate allowed to the secondary battery.
[0012]
Additionally, regarding the present invention, the peak cutting unit is preferably
configured to, in a case that a regenerative power generated by the load is larger than or
equal to a transmission peak-cut power set as a power transmittable to a wire, have the
secondary battery charged at a power rate that is larger than or equal to a difference
between the regenerative power and the transmission peak-cut power. The improving
power value calculating unit is preferably configured to calculate a charge improving
power value defined as a power value that increases as the charging rate of the secondary
EN Translation of Original JP Specification
5
battery becomes lower than the target charging rate of the secondary battery. The
charging rate improving unit is preferably configured to, in a case that the regenerative
power is smaller than or transmission peak-cut power, have the secondary battery
charged at a power rate that is smaller than or equal to the charge improving power value
calculated by the improving power value calculating unit.
[0013]
Further, regarding the present invention, the peak cutting unit is preferably
configured to have the secondary battery charged at a power rate equal to the charge
improving power value, in a case that the regenerative power is larger than or equal to the
transmission peak-cut power, and the charge improving power value is larger than or
equal to a difference between the regenerative power and the transmission peak-cut
power.
[0014]
Moreover, regarding the present invention, the peak cutting unit is preferably
configured to have the secondary battery charged at a power rate that is smaller than a
maximum charge power value for charge allowed by the secondary battery.
[0015]
Additionally, regarding the present invention, the charge and discharge control
device preferably further includes a charge terminating unit configured to terminate
charge by the peak cutting unit in a case that the charging rate of the secondary battery
exceeds a maximum charging rate allowed to the secondary battery.
[0016]
Further, the present invention is a charge and discharge control device
configured to control charge and discharge of a secondary battery coupled to a load
capable of generating a regenerative power. The charge and discharge control device
EN Translation of Original JP Specification
6
includes: a peak cutting unit configured to, in a case that a regenerative power generated
by the load is larger than or equal to a transmission peak-cut power set as a power
transmittable to a wire, have the secondary battery charged at a power rate that is larger
or equal to a difference between the regenerative power and the transmission peak-cut
power; an improving power value calculating unit configured to calculate a charge
improving power value defined as a power value that increases as a charging rate of the
secondary battery becomes smaller than a target charging rate; and a charging rate
improving unit configured to, in a case that the regenerative power is smaller than or
equal to the transmission peak-cut power, have the secondary battery charged at a power
rate that is smaller than or equal to the charge improving power value calculated by the
improving power value calculating unit.
[0017]
Moreover, regarding the present invention, the peak cutting unit is preferably
configured to have the secondary battery charged at a power rate equal to the charge
improving power value, in a case that the regenerative power is larger than or equal to the
transmission peak-cut power, and the charge improving power value is larger than or
equal to a value of a difference between the regenerative power and the transmission
peak-cut power.
[0018]
Additionally, the present invention is a charge and discharge control method
using a charge and discharge control device configured to control charge and discharge of
a secondary battery coupled to a load capable of generating a regenerative power. The
charge and discharge control method includes: in a case that a required power required by
the load is larger than or equal to a reception peak-cut power set as a power receivable
from a wire, a peak cutting unit having the secondary battery discharged at a power rate
EN Translation of Original JP Specification
7
that is larger or equal to a difference between the required power and the reception
peak-cut power; an improving power value calculating unit calculating a discharge
improving power value defined as a power value that increases as a charging rate of the
secondary battery becomes larger than a target charging rate; and in a case that the
required power is smaller than or equal to the reception peak-cut power, a charging rate
improving unit having the secondary battery discharged at a power rate that is smaller
than or equal to the discharge improving power value calculated by the improving power
value calculating unit.
[0019]
Further, the present invention is a charge and discharge control method using a
charge and discharge control device configured to control charge and discharge of a
secondary battery coupled to a load capable of generating a regenerative power. The
charge and discharge control device includes: in a case that a regenerative power
generated by the load is larger than or equal to a transmission peak-cut power set as a
power transmittable to a wire, a peak cutting unit having the secondary battery charged at
a power rate that is larger or equal to a difference between the regenerative power and the
transmission peak-cut power; an improving power value calculating unit calculating a
charge improving power value defined as a power value that increases as a charging rate
of the secondary battery becomes smaller than a target charging rate; and in a case that
the regenerative power is smaller than or equal to the transmission peak-cut power, a
charging rate improving unit having the secondary battery charged at a power rate that is
smaller than or equal to the charge improving power value calculated by the improving
power value calculating unit.
[0020]
Moreover, the present invention is a program to cause a charge and discharge
EN Translation of Original JP Specification
8
control device configured to control charge and discharge of a secondary battery coupled
to a load capable of generating a regenerative power, to function as: a peak cutting unit
configured to, in a case that a required power required by the load is larger than or equal
to a reception peak-cut power set as a power receivable from a wire, have the secondary
battery discharged at a power rate that is larger or equal to a difference between the
required power and the reception peak-cut power; an improving power value calculating
unit configured to calculate a discharge improving power value defined as a power value
that increases as a charging rate of the secondary battery becomes larger than a target
charging rate; and a charging rate improving unit configured to, in a case that the
required power is smaller than or equal to the reception peak-cut power, have the
secondary battery discharged at a power rate that is smaller than or equal to the discharge
improving power value calculated by the improving power value calculating unit.
[0021]
Additionally, the present invention is a program to cause a charge and discharge
control device configured to control charge and discharge of a secondary battery coupled
to a load capable of generating a regenerative power, to function as: a peak cutting unit
configured to, in a case that a regenerative power generated by the load is larger than or
equal to a transmission peak-cut power set as a power transmittable to a wire, have the
secondary battery charged at a power rate that is larger or equal to a difference between
the regenerative power and the transmission peak-cut power; an improving power value
calculating unit configured to calculate a charge improving power value defined as a
power value that increases as a charging rate of the secondary battery becomes smaller
than a target charging rate; and a charging rate improving unit configured to, in a case
that the regenerative power is smaller than or equal to the transmission peak-cut power,
have the secondary battery charged at a power rate that is smaller than or equal to the
EN Translation of Original JP Specification
9
charge improving power value calculated by the improving power value calculating unit.
Effects of the Invention
[0022]
According to the present invention, a peak cutting process is performed using a
secondary battery when the required power or the regenerative power is larger than or
equal to the peak cut power. When the required power or the regenerative power is
smaller than the peak cut power, the charging rate of the secondary battery is improved.
Thus, it is possible to adjust the charging rate of the secondary battery while performing a
peak cut process.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023]
FIG. 1 is a schematic block diagram illustrating a configuration of a vehicle
including a charge and discharge control device according to a first embodiment of the
present invention.
FIG. 2 is a flowchart illustrating processing of a charge and discharge control
device according to the first embodiment of the present invention.
FIG. 3 is a diagram illustrating a specific example of a state at the time the
charge and discharge control device of the first embodiment of the present invention
performs charge and discharge control on a secondary battery.
FIG. 4 is a schematic block diagram illustrating a configuration of the vehicle
including the charge and discharge control device according to a second embodiment of
the present invention.
FIG. 5 is a flowchart illustrating processing of a charge and discharge control
EN Translation of Original JP Specification
10
device according to a second embodiment of the present invention.
FIG. 6 is a diagram illustrating a specific example of a state at the time the
charge and discharge control device of the second embodiment of the present invention
performs charge and discharge control on a secondary battery.
FIG. 7 is a schematic block diagram illustrating a configuration of a vehicle
including a charge and discharge control device according to a fourth embodiment of the
present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0024]
Hereinafter, embodiments of the present invention will be described in detail
with reference to drawings.
[0025]
<>
FIG. 1 is a schematic block diagram illustrating a configuration of a vehicle 100
including a charge and discharge control device 150 according to a first embodiment of
the present invention.
The vehicle 100 of the present embodiment includes an inverter 110, a load 120,
a DC-DC converter 130, a secondary battery 140, and a charge and discharge control
device 150.
The inverter 110 converts into the alternate-current power, the direct-current
power supplied from a wire 200 and the direct-current power supplied from the
secondary battery 140 via the DC-DC converter 130.
The load 120 has the vehicle 100 run using the alternate-current power
converted by the inverter 110. Additionally, the load 120 has the vehicle 100 perform
EN Translation of Original JP Specification
11
regenerative braking, thereby causing the regenerative power to be generated. The
regenerative power is fed to the wire 200 and the secondary battery 140 via the inverter
110.
The DC-DC converter 130 converts the voltage of the power supplied from the
wire 200 and the load 120 and the voltage of the power supplied from the secondary
battery 140.
The secondary battery 140 is coupled to the wire 200 and the load 120 via the
DC-DC converter 130. The secondary battery 140 is charged using the power supplied
from the wire 200 and the load 120. Additionally, the secondary battery 140 supplies
the power to the load 120 via the DC-DC converter 130.
[0026]
The charge and discharge control device 150 is a device that controls charge and
discharge of the secondary battery 140. The charge and discharge control device 150
includes a load power monitoring unit 151, a mode control unit 152, a peak cutting unit
153, a charging rate monitoring unit 154, an improving power value calculating unit 155,
and a charging rate improving unit 156.
[0027]
The load power monitoring unit 151 monitors the required power required for
the load 120 to have the vehicle run, and a value of the regenerative power generated by
the load 120. Hereinafter, the required power and the regenerative power are
collectively referred to as the “load power”.
The mode control unit 152 changes, based on the load power, a control mode
that controls charge and discharge of the secondary battery 140 to one of a wire preferred
mode or a battery preferred mode. The wire preferred mode is a mode that prefers to
use a power supply from the wire 200. The battery preferred mode is a mode that
EN Translation of Original JP Specification
12
prefers to improve charging rate of the secondary battery 140.
[0028]
The peak cutting unit 153, when the control mode is set to the wire preferred
mode, outputs to the DC-DC converter 130, an instruction to control the amount of
power by which the secondary battery 140 is charged or discharged, so that the power
received from or fed to the wire 200 does not exceed a predetermined peak-cut power.
Specifically, when the vehicle 100 is running, the peak cutting unit 153 outputs a
discharge instruction to have the secondary battery 140 discharged at a power rate equal
to a value of a difference between the required power and the reception peak-cut power
that is the maximum value of the power receivable from the wire 200. On the other
hand, when the vehicle 100 is braking, the peak cutting unit 153 outputs a charge
instruction to have the secondary battery 140 charged at a power rate equal to a value of a
difference between the regenerative power and the transmission peak-cut power that is
the maximum value of the power transmittable to the wire 200.
[0029]
The charging rate monitoring unit 154 monitors a charging rate of the secondary
battery 140. The monitoring of the secondary battery 140 can be performed by
measuring the open circuit voltage of the secondary voltage 140 and specifying the
charging rate associated with the open circuit voltage.
The improving power value calculating unit 155 calculates an improving power
value representing a power value required to have the charging rate of the secondary
battery 140 reach a predetermined target charging rate. Here, calculation of the
improving power value is performed by PI control. Here, as a difference between the
charging rate of the secondary battery 140 and the target charging rate becomes larger,
the improving power value becomes larger. Specifically, when the charging rate of the
EN Translation of Original JP Specification
13
secondary battery 140 is larger than the target charging rate, the improving power value
used to discharge the secondary battery 140 (discharge improving power value) increases
as the difference between the charging rate of the secondary battery 140 and the target
charging rate increases. On the other hand, when the charging rate of the secondary
battery 140 is smaller than the target charging rate, the improving power value used to
charge the secondary battery 140 (charge improving power value) increases as the
difference between the charging rate of the secondary battery 140 and the target charging
rate increases.
The charging rate improving unit 156, when the control mode is set to the
battery preferred mode, outputs to the DC-DC converter 130, an instruction to control the
power rate at which the secondary battery 140 is charged or discharged, based on the
improving power value.
[0030]
Next, processing of the charge and discharge control device 150 according to the
present embodiment is described.
FIG. 2 is a flowchart illustrating the processing of the charge and discharge
control device 150 according to the first embodiment of the present invention.
When a train initiates running, the load power monitoring unit 151 obtains the
load power (step S1). Then, the load power monitoring unit 151 determines whether the
load 120 is under a running operation or a braking operation (step S2).
[0031]
If the load power monitoring unit 151 determines that the load 120 is under the
running operation (step S2: YES), the mode control unit 152 determines whether or not
the required power is larger than the preset reception peak-cut power (step S3). If the
mode control unit 152 determines that the required power is larger than the preset
EN Translation of Original JP Specification
14
reception peak-cut power (step S3: YES), the mode control unit 152 changes the control
mode to the wire preferred mode (step S4). Here, if the control mode is already set to
the wire preferred mode, there is no need to change the control mode.
[0032]
If the control mode of the mode control unit 152 is set to the wire preferred
mode, the peak cutting unit 153 outputs to the DC-DC converter 130, a discharge
instruction to discharge the secondary battery 140 at a power rate obtained by dividing a
value of the difference between the required power and the reception peak-cut power by
the efficiency of the DC-DC converter 130 (step S5). Then, the processing returns to
step S1, and the charge and discharge control device 150 performs charge and discharge
control at the next time.
[0033]
On the other hand, if the mode control unit 152 determines that the required
power is smaller than or equal to the preset reception peak-cut power (step S3: NO), the
mode control unit 152 changes the control mode to the battery preferred mode (step S6).
Here, if the control mode is already set to the battery preferred mode, there is no need to
change the control mode.
[0034]
When the control mode of the mode control unit 152 is set to the battery
preferred mode, the charging rate monitoring unit 154 obtains the charging rate of the
secondary battery 140. Then, the improving power value calculating unit 155
determines whether or not the charging rate of the secondary battery 140 is larger than
the preset target charging rate (step S7). If the charging rate of the secondary battery
140 is smaller than or equal to the target charging rate (step S7: NO), discharge of the
secondary battery 140 is not performed and the processing returns to step S1, since the
EN Translation of Original JP Specification
15
difference between the charging rate of the secondary battery 140 and the target charging
rate becomes larger if the secondary battery 140 is discharged.
[0035]
On the other hand, if the charging rate of the secondary battery 140 is larger than
the target charging rate (step S7: YES), the improving power value calculating unit 155
calculates, by PI control, a discharge improving power value based on the charging rate
of the secondary battery 140 and the target charging rate (step S8). Then, the charging
rate improving unit 156 determines whether or not the power value obtained by dividing
the required power by the efficiency of the DC-DC converter 130 is smaller than or equal
to the discharge improving power value (step S9).
[0036]
If the charging rate improving unit 156 determines that the power value obtained
by dividing the required power by the efficiency of the DC-DC converter 130 is smaller
than or equal to the discharge improving power value (step S9: YES), the charging rate
improving unit 156 outputs to the DC-DC converter 130, a discharge instruction to have
the secondary battery 140 discharged at a power rate obtained by dividing the required
power by the efficient (step S10). Thus, the power required by the load 120 is supplied
from the secondary battery 140. Consequently, the charging rate of the secondary
battery 140 becomes closer to the target charging rate. Then, the processing returns to
step S1, and the charge and discharge control device 150 performs charge and discharge
control at the next time.
[0037]
On the other hand, if the charging rate improving unit 156 determines that the
power value obtained by dividing the required power by the efficiency of the DC-DC
converter 130 is larger than the discharge improving power value (step S9: NO), the
EN Translation of Original JP Specification
16
charging rate improving unit 156 outputs to the DC-DC converter 130, a discharge
instruction to have the secondary battery 140 discharged at a power rate equal to the
discharge improving power value (step S11). Thus, the charging rate of the secondary
battery 140 becomes closer to the target charging rate. At this time, similar to step S10,
if control is made to supply all the power required by the load 120 from the secondary
battery 140, the charging rate of the secondary battery 140 might be below the target
charging rate. For this reason, the secondary battery 140 is discharged at a power rate
equal to the discharge improving power value, and the rest of the required power is
supplied from the wire 200, thereby making it possible to adequately control charge and
discharge so that the charging rate of the secondary battery 140 becomes closer to the
target charging rate.
Then, the processing returns to step S1, and the charge and discharge control
device 150 performs charge and discharge control at the next time.
[0038]
In step S2, if the load power monitoring unit 151 determines that the load 120 is
under the regenerative breaking operation (step S2: NO), the mode control unit 152
determines whether or not the regenerative power is larger than the preset transmission
peak-cut power (step S12). If the mode control unit 152 determines that the
regenerative power is larger than the transmission peak-cut power (step S12: YES), the
mode control unit 152 changes the control mode to the wire preferred mode (step S13).
Here, if the control mode is already set to the wire preferred mode, there is no need to
change the control mode.
[0039]
When the control mode of the mode control unit 152 is set to the wire preferred
mode, the peak cutting unit 153 outputs to the DC-DC converter 130, a charge instruction
EN Translation of Original JP Specification
17
to have the secondary battery 140 charged at a power rate obtained by multiplying a
value of a difference between the regenerative power and the transmission peak-cut
power by the efficiency of the DC-DC converter 130 (step S14). Then, the processing
returns to step S1, and the charge and discharge control device 150 performs charge and
discharge control at the next time.
[0040]
On the other hand, if the mode control unit 152 determines that the regenerative
power is smaller than or equal to the preset transmission peak-cut power (step S12: NO),
the mode control unit 152 changes the control mode to the battery preferred mode (step
S15). Here, if the control mode is already set to the battery preferred mode, there is no
need to change the control mode.
[0041]
When the control mode of the mode control unit 152 is set to the battery
preferred mode, the charging rate monitoring unit 154 obtains the charging rate of the
secondary battery 140. Then, the improving power value calculating unit 155
determines whether or not the charging rate of the secondary battery 140 is smaller than
the target charging rate (step S16). If the charging rate of the secondary battery 140 is
larger than or equal to the target charging rate (step S16: NO), charge of the secondary
battery 140 is not performed and the processing returns to step S1, since the difference
between the charging rate of the secondary battery 140 and the target charging rate
becomes larger if the secondary battery 140 is charged.
[0042]
On the other hand, if the charging rate of the secondary battery 140 is smaller
than the target charging rate (step S16: YES), the improving power value calculating unit
155 calculates, by PI control, a charge improving power value based on the charging rate
EN Translation of Original JP Specification
18
of the secondary battery 140 and the target charging rate (step S17). Then, the charging
rate improving unit 156 determines whether or not a power value obtained by multiplying
the regenerative power by the efficiency of the DC-DC converter 130 is smaller than or
equal to the charge improving power value (step S18).
[0043]
If the charging rate improving unit 156 determines that the power value obtained
by multiplying the regenerative power by the efficiency of the DC-DC converter 130 is
smaller than or equal to the charge improving power value (step S18: YES), the charging
rate improving unit 156 outputs to the DC-DC converter 130, a charge instruction to have
the secondary battery 140 charged at a power rate obtained by multiplying the
regenerative power by the efficient (step S19). Thus, all the regenerative power
generated by the load 120 is stored in the secondary battery 140. Consequently, the
charging rate of the secondary battery 140 becomes closer to the target charging rate.
Then, the processing returns to step S1, and the charge and discharge control device 150
performs charge and discharge control at the next time.
[0044]
On the other hand, if the charging rate improving unit 156 determines that the
power value obtained by multiplying the regenerative power by the efficiency of the
DC-DC converter 130 is larger than the charge improving power value (step S18: YES),
the charging rate improving unit 156 outputs to the DC-DC converter 130, a charge
instruction to have the secondary battery 140 charged at a power rate equal to the charge
improving power value (step S20). Thus, the charging rate of the secondary battery 140
becomes closer to the target charging rate. At this time, similar to step S19, if control is
made to supply all the regenerative power generated by the load 120 to the secondary
battery 140 for charging, the charging rate of the secondary battery 140 might exceed the
EN Translation of Original JP Specification
19
target charging rate. For this reason, the secondary battery 140 is charged at the power
rate equal to the charge improving power value, and the surplus power is collected by the
wire 200, thereby making it possible to adequately control charge and discharge so that
the charging rate of the secondary battery 140 becomes closer to the target charging rate.
Then, the processing returns to step S1, and the charge and discharge control
device 150 performs charge and discharge control at the subsequent time.
[0045]
The above processes from step S1 to step S20 are repeatedly performed, thereby
making it possible to implement the peak-cut of the powers supplied from and corrected
by the wire 200 and to perform a control so that the charging rate of the secondary
battery 140 becomes closer to the target charging rate.
[0046]
Next, charge and discharge control of the secondary battery 140 performed by
the charge and discharge control device 150 of the present embodiment is described with
reference to a specific example.
FIG. 3 is a diagram illustrating a specific example of the state at the time the
charge and discharge control device 150 of the first embodiment of the present invention
performs charge and discharge control on the secondary battery 140.
First, at time t0, the load power monitoring unit 151 obtains the load power and
determines in step S2 that the load 120 is under the running operation. Then, the mode
control unit 152 compares the required power of the load 120 and the reception peak-cut
power, in step S3. At time t0, the required power of the load 120 is smaller than the
reception peak-cut power, as shown in FIG. 3(A). For this reason, in step S6, the mode
control unit 152 changes the control mode to the battery preferred mode, as shown in FIG.
3(C).
EN Translation of Original JP Specification
20
[0047]
Then, the improving power value calculating unit 155 determines whether or not
the charging rate of the secondary battery 140 is larger than the target charging rate. At
time t0, the charging rate of the secondary battery 140 is larger than the target charging
rate, as shown in FIG. 3(B). For this reason, in step S8, the improving power value
calculating unit 155 calculates a discharge improving power value, as shown in FIG.
3(A).
[0048]
Then, the charging rate improving unit 156 compares the discharge improving
power value and a power value obtained by dividing the required power by the efficiency
of the DC-DC converter 130, in step S9. At time t0, the power value obtained by
dividing the required power by the efficiency of the DC-DC converter 130 is smaller than
or equal to the discharge improving power value, as shown in FIG. 3(A). For this
reason, in step S10, the charging rate improving unit 156 outputs a discharge instruction
to have the secondary battery 140 discharged at the power rate obtained by dividing the
required power by the efficiency of the DC-DC converter 130.
[0049]
Then, at time t1, the power value obtained by dividing the required power by the
efficiency of the DC-DC converter 130 exceeds the discharge improving power value, as
shown in FIG. 3(A). For this reason, in step S11, the charging rate improving unit 156
outputs a discharge instruction to have the secondary battery 140 discharged at the power
rate equal to the discharge improving power value. Then, the differential power
between the required power and the power supplied from the secondary battery 140 is
supplied from the wire 200 to the load 120, as shown in FIG. 3(A).
[0050]
EN Translation of Original JP Specification
21
Then, at time t2, the required power of the load 120 exceeds the reception
peak-cut power, as shown in FIG. 3(A). For this reason, in step S4, the mode control
unit 152 changes the control mode to the wire preferred mode. Then, the peak cutting
unit 153 outputs a discharge instruction to have the second battery 140 discharged at a
power rate obtained by dividing the difference between the required power and the
reception peak-cut power by the efficiency of the DC-DC converter 130. At this time,
the power supplied from the wire 200 becomes the reception peak-cut power.
[0051]
Then, at time t3, the required power of the load 120 becomes below the reception
peak-cut power, as shown in FIG. 3(A). For this reason, in step S6, the mode control
unit 152 changes the control mode to the battery preferred mode. Additionally, at time
t3, the charging rate of the secondary battery 140 reaches the target charging rate, as
shown in FIG. 3(B). For this reason, in the process at the time t3, the charge and
discharge control device 150 does not output a discharge instruction to the DC-DC
converter 130 in accordance with the result of the determination in step S7. For this
reason, all the required power of the load 120 is supplied from the wire 200.
[0052]
Then, at time t4, the load 120 generates the regenerative power, as shown in FIG.
3(A). For this reason, in step S12, the mode control unit 152 compares the regenerative
power of the load 120 and the transmission peak-cut power. At time t4, the regenerative
power of the load 120 becomes larger than or equal to the transmission peak-cut power,
as shown in FIG. 3(A). For this reason, the mode control unit 152 changes the control
mode to the wire preferred mode, in step S13, as shown in FIG. 3(C).
[0053]
Then, the peak cutting unit 153 outputs a charge instruction to have the
EN Translation of Original JP Specification
22
secondary battery 140 charged at a power rate obtained by the multiplying the difference
between the regenerative power and the transmission peak-cut power by the efficiency of
the DC-DC converter 130. At this time, the power collected by the wire 200 becomes
the transmission peak-cut power. Additionally, by charging the secondary battery 140 at
time t4, the charging rate of the secondary battery 140 becomes larger than the target
charging rate, as shown in FIG. 3(B).
[0054]
Then, at time t5, the regenerative power of the load 120 becomes below the
transmission peak-cut power, as shown in FIG. 3(A). For this reason, in step S15, the
mode control unit 152 changes the control mode to the battery preferred mode.
Additionally, at time t5, the charging rate of the secondary battery 140 is larger than the
target charging rate, as shown in FIG. 3(B). For this reason, the charge and discharge
control device 150 does not output a charge instruction to the DC-DC converter 130 in
accordance with a result of the determination in step S16. For this reason, all the
regenerative power of the load 120 is collected by the wire 200.
[0055]
Then, at time t6, the operation of the load 120 changes from the regenerative
breaking operation to the running operation, as shown in FIG. 3(A). Additionally, at
time t6, the charging rate of the secondary battery 140 is larger than the target charging
rate, as shown in FIG. 3(B). For this reason, in step S9, the improving power value
calculating unit 156 compares the discharge improving power value and a power value
obtained by dividing the required power by the efficiency of the DC-DC converter 130.
At time t6, the power value obtained by dividing the required power by the efficiency of
the DC-DC converter 130 is smaller than or equal to the discharge improving power
value, as shown in FIG. 3(A). For this reason, in step S10, the charging rate improving
EN Translation of Original JP Specification
23
unit 156 outputs a discharge instruction to have the secondary battery 140 discharged at
the power rate obtained by dividing the required power by the efficiency of the DC-DC
converter 130. Thus, the charging rate of the secondary battery 140 becomes closer to
the target charging rate, again.
[0056]
As explained above, according to the present embodiment, the charge and
discharge control device 150 has the secondary battery 140 discharged at a power rate
that is larger than or equal to the difference between the required power and the reception
peak-cut power when the required power of the load 120 is larger than or equal to the
reception peak-cut power. When the required power of the load 120 is smaller than the
reception peak-cut power, the discharge control device 150 has the secondary battery 140
discharged at a power rate that is smaller than or equal to the discharge improving power
value.
Additionally, according to the present embodiment, the charge and discharge
control device 150 has the secondary battery 140 charged at the power rate that is larger
than or equal to the difference between the regenerative power and the transmission
peak-cut power when the regenerative power of the load 120 is larger than or equal to the
transmission peak-cut power. When the regenerative power of the load 120 is smaller
than the transmission peak-cut power, the charge and discharge control device 150 has
the secondary battery 140 charged at the power rate that is smaller than or equal to the
charge improving power value.
Thus, it is possible to adjust the charging rate of the secondary battery 140 while
cutting the peaks of the power transmitted to the wire 200 and the power received from
the wire 200.
[0057]
EN Translation of Original JP Specification
24
Descriptions have been given in the present embodiment with respect to the case
where the peak cutting unit 153, in the wire preferred mode, control charge and discharge
of the secondary battery 140 so that the power supplied from or collected by the wire 200
becomes the peak-cut power. However, the configuration is not limited thereto. In
other words, as long as the power supplied from or collected by the wire 200 does not
become larger than or equal to the peak-cut power, the peak cutting unit 153 may be
configured to control charge and discharge of the secondary battery 140 so that the power
received from or transmitted to the wire 200 becomes smaller than or equal to the
peak-cut power.
[0058]
<>
Next, a second embodiment of the present invention is described here.
FIG. 4 is a schematic block diagram illustrating a configuration of the vehicle
100 including the charge and discharge control device 150 according to a second
embodiment of the present invention.
The charge and discharge control device 150 of the second embodiment does not
include the mode control unit 152 included in the charge and discharge control device
150 of the first embodiment, but includes a power determining unit 157. The power
determining unit 157 outputs to the DC-DC converter 130, an instruction to have the
secondary battery 140 charged or discharged at a power rate that is larger of the powers
to charge or discharge the secondary battery 140, which are output from the peak cutting
unit 153 and the charging rate improving unit 156.
[0059]
Next, processing of the charge and discharge control device 150 of the second
embodiment is described here.
EN Translation of Original JP Specification
25
FIG. 5 is a flowchart illustrating the processing of the charge and discharge
control device 150 according to the second embodiment of the present invention.
When a train initiates running, the load power monitoring unit 151 obtains the
load power (step S101). Then, the load power monitoring unit 151 determines whether
the load 120 is under a running operation or a braking operation (step S102).
[0060]
If the load power monitoring unit 151 determines that the load 120 is under the
running operation (step S102: YES), the peak cutting unit 153 determines whether or not
the required power is larger than the preset reception peak-cut power (step S103). If the
peak cutting unit 153 determines that the required power is larger than the preset
reception peak-cut power (step S103: YES), the peak cutting unit 153 calculates, as a first
power value, a power value obtained by dividing a value of the difference between the
required power and the reception peak-cut power by the efficiency of the DC-DC
converter 130 (step S104). On the other hand, if the peak cutting unit 153 determines
that the required power is smaller than or equal to the preset reception peak-cut power
(step S103: NO), the peak cutting unit 153 sets the first power value to be zero (step
S105).
[0061]
After the peak cutting unit 153 calculates the first power value in step S104 or
step S105, the charging rate monitoring unit 154 obtains the charging rate of the
secondary battery 140. Then, the improving power value calculating unit 155 calculates,
by PI control, a discharge improving power value based on the charging rate of the
secondary battery 140 and the target charging rate (step S106). Here, if the charging
rate of the secondary battery 140 is smaller than the target charging rate, the discharge
improving power value becomes zero. Then, the charging rate improving unit 156
EN Translation of Original JP Specification
26
determines whether or not the power value obtained by dividing the required power by
the efficiency of the DC-DC converter 130 is smaller than or equal to the discharge
improving power value (step S107).
[0062]
If the charging rate improving unit 156 determines that the power value obtained
by dividing the required power by the efficiency of the DC-DC converter 130 is smaller
than or equal to the discharge improving power value (step S107: YES), the charging rate
improving unit 156 calculates, as a second power value, the power value obtained by
dividing the required power by the efficiency (step S108). On the other hand, if the
charging rate improving unit 156 determines that the power value obtained by dividing
the required power by the efficiency of the DC-DC converter 130 is larger than the
discharge improving power value (step S107: NO), the charging rate improving unit 156
sets the second power value to be the discharge improving power value (step S109).
[0063]
After the charging rate improving unit 156 calculates the second power value in
step S108 or S109, the power determining unit 157 determines whether or not the first
power value calculated by the peak cutting unit 153 is larger than the second power value
calculated by the charging rate improving unit 156 (step S110). If the power
determining unit 157 determines that the first power value is larger than the second
power value (step S110: YES), the power determining unit 157 outputs to the DC-DC
converter 130, a discharge instruction to have the secondary battery 140 discharged at a
power rate equal to the first power value (step S111). On the other hand, if the power
determining unit 157 determines that the first power value is smaller than or equal to the
second power value (step S110: NO), the power determining unit 157 outputs to the
DC-DC converter 130, a discharge instruction to have the secondary battery 140
EN Translation of Original JP Specification
27
discharged at a power rate equal to the second power value (step S112).
Then, the processing returns to step S101 and the charge and discharge control
device 150 performs charge and discharge control at the subsequent time.
[0064]
On the other hand, in step S102, if the load power monitoring unit 151
determines that the load 120 is under the regenerative breaking operation (step S102:
NO), the peak cutting unit 153 determines whether or not the regenerative power is larger
than the preset transmission peak-cut power (step S113). If the peak cutting unit 153
determines that the regenerative power is larger than the preset transmission peak-cut
power (step S113: YES), the peak cutting unit 153 calculates, as a first power value, a
power value obtained by multiplying a value of the difference between the regenerative
power and the transmission peak-cut power by the efficiency of the DC-DC converter
130 (step S114). On the other hand, if the peak cutting unit 153 determines that the
regenerative power is smaller than or equal to the preset transmission peak-cut power
(step S103: NO), the peak cutting unit 153 sets the first power value to be zero (step
S115).
[0065]
After the peak cutting unit 153 calculates the first power value in step S114 or
step S115, the charging rate monitoring unit 154 obtains the charging rate of the
secondary battery 140. Then, the improving power value calculating unit 155 calculates,
by PI control, a charge improving power value based on the charging rate of the
secondary battery 140 and the target charging rate (step S116). Here, when the charging
rate of the secondary battery 140 is smaller than the target charging rate, the charge
improving power value becomes zero. Then, the charging rate improving unit 156
determines whether or not the power value obtained by multiplying the regenerative
EN Translation of Original JP Specification
28
power by the efficiency of the DC-DC converter 130 is smaller than or equal to the
charge improving power value (step S117).
[0066]
If the charging rate improving unit 156 determines that the power value obtained
by multiplying the regenerative power by the efficiency of the DC-DC converter 130 is
smaller than or equal to the charge improving power value (step S117: YES), the
charging rate improving unit 156 calculates, as a second power value, the power value
obtained by multiplying the regenerative power by the efficiency (step S118). On the
other hand, if the charging rate improving unit 156 determines that the power value
obtained by multiplying the regenerative power by the efficiency of the DC-DC converter
130 is larger than the charge improving power value (step S117: NO), the charging rate
improving unit 156 sets the second power value to be the charge improving power value
(step S119).
[0067]
After the charging rate improving unit 156 calculates the second power value in
step S118 or S119, the power determining unit 157 determines whether or not the first
power value calculated by the peak cutting unit 153 is larger than the second power value
calculated by the charging rate improving unit 156 (step S120). If the power
determining unit 157 determines that the first power value is larger than the second
power value (step S120: YES), the power determining unit 157 outputs to the DC-DC
converter 130, a charge instruction to have the secondary battery 140 charged at the
power rate equal to the first power value (step S121). On the other hand, if the power
determining unit 157 determines that the first power value is smaller than or equal to the
second power value (step S120: NO), the power determining unit 157 outputs to the
DC-DC converter 130, a charge instruction to have the secondary battery 140 charged at
EN Translation of Original JP Specification
29
the power rate equal to the second power value (step S122).
Then, the processing returns to step S101, and the charge and discharge control
device 150 performs charge and discharge control at the subsequent time.
[0068]
The above processes from step S101 to step S122 are repeatedly performed,
thereby making it possible to implement the peak-cut of the powers supplied from and
corrected by the wire 200 and to perform a control so that the charging rate of the
secondary battery 140 becomes closer to the target charging rate. Particularly,
according to the second embodiment, it is possible to perform a control so that the
charging rate of the secondary battery 140 becomes closer to the target charging rate
faster than in the first embodiment.
[0069]
Next, charge and discharge control of the secondary battery 140 performed by
the charge and discharge control device 150 according to the present embodiment is
described with reference a specific example.
FIG. 6 is a diagram illustrating a specific example of the state at the time the
charge and discharge control device 150 of the second embodiment of the present
invention performs charge and discharge control on the secondary battery 140.
First, at time t0, the load power monitoring unit 151 obtains the load power and
determines in step S102 that the load 120 is under the running operation. At this time,
the required power of the load 120 is smaller than the reception peak-cut power as shown
in FIG. 6(A). For this reason, in step S105, the peak cutting unit 153 sets the first power
value to be zero. On the other hand, the power value obtained by dividing the required
power by the efficiency of the DC-DC converter 130 is smaller than or equal to the
discharge improving power value, as shown in FIG. 6(A). For this reason, in step S108,
EN Translation of Original JP Specification
30
the charging rate improving unit 156 sets the second power value to be the power value
obtained by dividing the required power by the efficiency of the DC-DC converter 130.
At this time, the first power value is smaller than or equal to the second power
value. For this reason, the power determining unit 157 outputs a discharge instruction
to have the secondary battery 140 discharged at the power rate equal to the second power
value, that is, the power value obtained by dividing the required power by the efficiency
of the DC-DC converter 130.
[0070]
Then, at time t1, the required power of the load 120 is smaller than the reception
peak-cut power, as shown in FIG. 6(A). For this reason, in step S105, the peak cutting
unit 153 sets the first power value to be zero. On the other hand, the power value
obtained by dividing the required power by the efficiency of the DC-DC converter 130 is
larger than the discharge improving power value, as shown in FIG. 6(A). For this
reason, in step S109, the charging rate improving unit 156 sets the second power value to
be the discharge improving power value.
At this time, the first power value is smaller than or equal to the second power
value. For this reason, the power determining unit 157 outputs a discharge instruction
to have the secondary battery 140 discharged at the power rate equal to the second power
value, that is, the discharge improving power. Then, the differential power between the
required power and the power supplied from the secondary battery 140 is supplied from
the wire 200 to the load 120, as shown in FIG. 6(A).
[0071]
Then, at time t2, the required power of the load 120 exceeds the reception
peak-cut power, as shown in FIG. 6(A). For this reason, in step S104, the peak cutting
unit 153 sets the first power value to be the power value obtained by dividing a value of
EN Translation of Original JP Specification
31
the difference between the required power and the reception peak-cut power by the
efficiency of the DC-DC converter 130. On the other hand, the power value obtained
by dividing the required power by the efficiency of the DC-DC converter 130 is larger
than the discharge improving power value, as shown in FIG. 6(A). For this reason, in
step S109, the charging rate improving unit 156 sets the second power value to be the
discharge improving power value.
At this time, the first power value is smaller than or equal to the second power
value. For this reason, the power determining unit 157 outputs a discharge instruction
to have the secondary battery 140 discharged at the power rate equal to the second power
value, that is, the discharge improving power value. In other words, according to the
present embodiment, even when the required power is larger than or equal to the
reception peak-cut power, as long as the discharge improving power value is larger than
or equal to the differential power between the required power and the reception peak-cut
power, the secondary battery 140 is discharged at the power rate equal to the discharge
improving power value.
[0072]
On the other hand, at time t3, the first power value becomes larger than the
second power value. For this reason, the power determining unit 157 outputs a
discharge instruction to have the secondary battery 140 discharged at the power rate
equal to the first power value, that is, the value of the difference between the required
power and the reception peak-cut power. At this time, the power supplied from the wire
200 becomes the reception peak-cut power.
[0073]
Then, at time t4, the required power of the load 120 becomes below the reception
peak-cut power, as shown in FIG. 6(A). For this reason, in step S105, the peak cutting
EN Translation of Original JP Specification
32
unit 153 sets the first power value to be zero. On the other hand, at time t4, the charging
rate of the secondary battery 140 is below the target charging rate, as shown in FIG. 6(B).
For this reason, the discharge improving power value is zero. Accordingly, the power
value obtained by dividing the required power by the efficiency of the DC-DC converter
130 is larger than the discharge improving power value. For this reason, in step S109,
the charging rate improving unit 156 sets the second power value to be the discharge
improving power value. In other words, the second power value becomes zero.
Accordingly, the first and second power values are zero. For this reason, the
power determining unit 157 outputs a discharge instruction to have the secondary battery
140 discharged at the power rate equal to zero. This is equivalent to that the discharge
instruction is not output. For this reason, all the required power of the load 120 is
supplied from the wire 200.
[0074]
Then, at time t5, the load power monitoring unit 151 obtains the load power and
determines in step S102 that the load 120 is under the regenerative breaking operation.
At this time, the regenerative power of the load 120 is larger than or equal to the
transmission peak-cut power, as shown in FIG. 6(A). For this reason, in step S114, the
peak cutting unit 153 sets the first power value to be a power value obtained by
multiplying a value of the difference between the regenerative power and the
transmission peak-cut power by the efficiency of the DC-DC converter 130. On the
other hand, the power value obtained by multiplying the regenerative power by the
efficiency of the DC-DC converter 130 is larger than the charge improving power value.
For this reason, in step S119, the charging rate improving unit 156 sets the second power
value to be the charge improving power value.
At this time, the first power value is larger than the second power value. For
EN Translation of Original JP Specification
33
this reason, the power determining unit 157 outputs a charge instruction to have the
secondary battery 140 charged at the power rate equal to the first power value, that is, the
power value obtained by multiplying the value of the difference between the regenerative
power and the transmission peak-cut power by the efficiency of the DC-DC converter
130.
[0075]
Then, at time t6, the regenerative power of the load 120 is larger than or equal to
the transmission peak-cut power, as shown in FIG. 6(A). For this reason, in step S115,
the peak cutting unit 153 sets the first power value to be zero. On the other hand, at
time t6, the charging rate of the secondary battery 140 is above the target charging rate, as
shown in FIG. 6(B). For this reason, the charge improving power value is zero.
Accordingly, the power value obtained by multiplying the regenerative power by the
efficiency of the DC-DC converter 130 is larger than the charge improving power value.
For this reason, in step S119, the charging rate improving unit 156 sets the second power
value to be the charge improving power value. In other words, the second power value
becomes zero.
Accordingly, the first and second power values are zero. For this reason, the
power determining unit 157 outputs a charge instruction to have the secondary battery
140 charged at the power rate equal to zero. This is equivalent to that the charge
instruction is not output. For this reason, all the regenerative power of the load 120 is
collected by the wire 200.
[0076]
Then, at time t7, the operation of the load 120 changes from the regenerative
braking operation to the running operation, as shown in FIG. 6(A). Additionally, the
required power of the load 120 is smaller than the reception peak-cut power, as shown in
EN Translation of Original JP Specification
34
FIG. 6(A). For this reason, in step S105, the peak cutting unit 153 sets the first power
value to be zero. On the other hand, the power value obtained by dividing the required
power by the efficiency of the DC-DC converter 130 is smaller than or equal to the
discharge improving power, as shown in FIG. 6(A). For this reason, in step S108, the
charging rate improving unit 156 sets the second power value to be the power value
obtained by dividing the required power by the efficiency of the DC-DC converter 130.
At this time, the first power value is smaller than or equal to the second power
value. For this reason, the power determining unit 157 outputs a discharge instruction
to have the secondary battery 140 discharged at the power rate equal to the second power
value, that is, the power value obtained by dividing the required power by the efficiency
of the DC-DC converter 130. Thus, the charging rate of the secondary battery 140
becomes closer to the target charging rate, again.
[0077]
As explained above, according to the present embodiment, the charge and
discharge control device 150 has the secondary battery 140 discharged at the power rate
equal to the discharge improving power value when the required power is larger than or
equal to the reception peak-cut power, and the discharge improving power is larger than
or equal to the value of the difference between the required power and the reception
peak-cut power.
Additionally, according to the present embodiment, the charge and discharge
control device 150 has the secondary battery 140 charged at the power rate equal to the
discharge improving power value when the regenerative power is larger than or equal to
the transmission peak-cut power, and the charge improving power is larger than or equal
to the value of the difference between the regenerative power and the transmission
peak-cut power.
EN Translation of Original JP Specification
35
Thus, it is possible to adjust the charging rate of the secondary battery 140 more
efficiently than in the first embodiment while cutting the peaks of the power transmitted
to the wire 200 and the power received from the wire 200. Additionally, determination
of the control mode is not performed, thereby making the control logic simpler than that
in the first embodiment. Further, it is possible in the second embodiment to prevent a
rapid variation of the power of the secondary battery, compared to the second
embodiment, thereby enabling a reduction in load on devices, such as the DC-DC
converter 130 and the inverter 110.
[0078]
Different from the first embodiment, descriptions have been given in the present
embodiment with respect to the case where determination of the control mode is not
performed. However, the configuration is not limited thereto. For example, the peak
cutting unit 153 may be configured to, when the control mode is set to the wire preferred
mode, if the discharge improving power value is larger than or equal to the power
obtained by dividing the difference between the required power and the reception
peak-cut power by the efficiency of the DC-DC converter 130, output an instruction to
have the secondary battery 140 discharged at the power rate equal to the discharge
improving power value, thereby achieving the same effect as that of the first embodiment.
Similarly, the peak cutting unit 153 may be configured to, when the control mode is set to
the wire preferred mode, if the charge improving power value is larger than or equal to
the power obtained by multiplying the difference between the required power and the
reception peak-cut power by the efficiency of the DC-DC converter 130, output an
instruction to have the secondary battery 140 charged at the power rate equal to the
charge improving power value, thereby achieving the same effect as that of the first
embodiment.
EN Translation of Original JP Specification
36
[0079]
<>
Next, processing of the charge and discharge control device 150 according to a
third embodiment of the present invention is described here.
The charge and discharge control device 150 of the third embodiment is
configured to perform a control such that the peak cutting unit 153 of the charge and
discharge control device 150 of the first or second embodiment outputs a control
instruction to have the secondary battery 140 charged or discharged within a use voltage
range or a use current range of the secondary battery 140. In other words, control is
made such that the peak cutting unit 153 outputs a discharge control instruction to have
the secondary battery 140 discharged at a power rate that is smaller than the maximum
discharge power value allowable by the second battery 140, and outputs a charge control
instruction to have the secondary battery 140 charged at a power rate that is smaller than
the maximum charge power value allowable by the second battery 140.
[0080]
Specifically, at the time the capacity of the secondary battery 140 is designed, a
configuration is made such that the power to be calculated by the peak cutting unit 153 in
step S5 or S104 becomes smaller than a power value obtained by multiplying a value of
the monitored voltage of the secondary battery 140 by the amount of the maximum
allowable discharge current. At this time, as the maximum allowable discharge current,
a current value obtained by dividing by an internal resistance of the secondary battery
140, a value obtained by subtracting the minimum allowable voltage of the secondary
battery 140 from the voltage of an open circuit of the secondary battery 140, may be
used.
[0081]
EN Translation of Original JP Specification
37
Additionally, at the time the capacity of the secondary battery 140 is designed, a
configuration is made such that the power to be calculated by the peak cutting unit 153 in
step S14 or S114 is smaller than a power value obtained by multiplying a value of the
monitored voltage of the secondary battery 140 by the amount of the minimum allowable
discharge current. At this time, as the minimum allowable discharge current, a current
value obtained by dividing by the internal resistance of the secondary battery 140, a value
obtained by subtracting the maximum allowable voltage of the secondary battery 140
from the voltage of the open circuit of the secondary battery 140, may be used.
[0082]
Thus, the charge and discharge control device 150 can control charge and
discharge of the secondary battery 140 within the use range of the secondary battery 140.
Here, when the use range is exceeded while the vehicle 100 is running, a margin is
previously provided for a power supplying device (not shown) that supplies the power to
the wire 200, or acceleration or deceleration of the vehicle 100 is adjusted, thereby
preventing the use range from being exceeded.
[0083]
<>
Next, a fourth embodiment of the present invention is described here.
FIG. 7 is a schematic block diagram illustrating a configuration of the vehicle
100 including the charge and discharge control device 150 according to the fourth
embodiment of the present invention.
The charge and discharge control device 150 of the fourth embodiment is
configured to further include a charge and discharge terminating unit 158 (a charge
terminating unit, a discharge terminating unit) in the charge and discharge control device
150 of the first embodiment. The charge and discharge terminating unit 158 terminates
EN Translation of Original JP Specification
38
discharge by the peak cutting unit 153 when the charging rate of the secondary battery
140 is smaller than the minimum charging rate allowable to the secondary battery 140.
Additionally, the charge and discharge terminating unit 158 terminates charge by the
peak cutting unit 153 when the charging rate of the secondary battery 140 exceeds the
maximum charging rate allowable to the secondary battery 140.
[0084]
Thus, the charge and discharge control device 150 can control charge and
discharge of the secondary battery 140 within the use range of the secondary battery 140.
Here, when the use range is exceeded while the vehicle 100 is running, a margin is
previously provided for a power supplying device (not shown) that supplies the power to
the wire 200, or acceleration or deceleration of the vehicle 100 is adjusted, thereby
preventing the use range from being exceeded.
Here, the charging rate improving unit 156 does not output a charge instruction
when the charging rate of the secondary battery 140 is larger than the target charging rate.
Additionally, the charging rate improving unit 156 does not output a discharge instruction
when the charging rate of the secondary battery 140 is smaller than the target charging
rate. For this reason, it is sufficient for the charge and discharge terminating unit 158 to
stop the peak cutting unit 153 to output the charge or discharge instruction.
[0085]
Some embodiments of the present invention have been described above with
reference to the drawings. However, the specific configuration is not limited to the
above, and various design modifications may be made without departing from the scope
of the present invention.
For example, descriptions have been given in the above embodiments with
respect to the case where control is performed with respect to both the charge processing
EN Translation of Original JP Specification
39
and the discharge processing. However, the configuration is not limited thereto. In
other words, a configuration may be such that the charge control method of the present
invention is used only at the time the secondary battery 140 is charged, and another
control method is used at the time the secondary battery 140 is discharged.
Alternatively, a configuration may be such that the discharge control method of the
present invention is used only at the time the secondary battery 140 is discharged, and
another control method is used at the time the secondary battery 140 is charged.
[0086]
The above charge and discharge control device 150 includes a computer system.
A program for implementing the above process of each processing unit is stored in a
computer-readable recording medium, so that a computer reads and executes the program
to perform the above process. Here, the “computer-readable recording medium”
includes a magnet disk, a magneto optical disk, a CD-ROM, a DVD-ROM, a
semiconductor memory, and the like. Additionally, the computer program may be
distributed to computers via communication lines, so that a computer receiving the
distribution can execute the program.
[0087]
Further, the program includes a program that executes part of the
aforementioned functions. Moreover, the program includes a program, called a
differential file (differential program), which can implement the aforementioned
functions in combination with the program already stored in the computer system.
INDUSTRIAL APPLICABILITY
[0088]
The present invention is applicable to wire-less vehicles mounted with
EN Translation of Original JP Specification
40
secondary batteries.
DESCRIPTION OF REFERENCE NUMERALS
[0089]
100: vehicle
110: inverter
120: load
130: DC-DC converter
140: secondary battery
150: charge and discharge control device
151: load power monitoring unit
152: mode control unit
153: peak cutting unit
154: charging rate monitoring unit
155: improving power value calculating unit
156: charging rate improving unit
157: power determining unit
158: charge and discharge terminating unit
200: wire
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CLAIMS
1. A charge and discharge control device configured to control charge and
discharge of a secondary battery coupled to a load capable of generating a regenerative
power, the charge and discharge control device comprising:
a peak cutting unit configured to, in a case that a required power required by the
load is larger than or equal to a reception peak-cut power set as a power receivable from
a wire, have the secondary battery discharged at a power rate that is larger or equal to a
difference between the required power and the reception peak-cut power;
an improving power value calculating unit configured to calculate a discharge
improving power value defined as a power value that increases as a charging rate of the
secondary battery becomes larger than a target charging rate; and
a charging rate improving unit configured to, in a case that the required power is
smaller than or equal to the reception peak-cut power, have the secondary battery
discharged at a power rate that is smaller than or equal to the discharge improving power
value calculated by the improving power value calculating unit.
2. The charge and discharge control device according to claim 1, wherein the peak
cutting unit is configured to have the secondary battery discharged at a power rate equal
to the discharge improving power value, in a case that the required power is larger than or
equal to the reception peak-cut power, and the discharge improving power value is larger
than or equal to a value of a difference between the required power and the reception
peak-cut power.
3. The charge and discharge control device according to claim 1 or 2, wherein the
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peak cutting unit is configured to have the secondary battery discharged at a power rate
that is smaller than a maximum discharge power value for discharge allowed by the
secondary battery.
4. The charge and discharge control device according to any one of claims 1 to 3,
further comprising:
a discharge terminating unit configured to terminate discharge by the peak
cutting unit in a case that the charging rate of the secondary battery is smaller than a
minimum charging rate allowed to the secondary battery.
5. The charge and discharge control device according to any one of claims 1 to 4,
wherein the peak cutting unit is configured to, in a case that a regenerative power
generated by the load is larger than or equal to a transmission peak-cut power set as a
power transmittable to a wire, have the secondary battery charged at a power rate that is
larger than or equal to a difference between the regenerative power and the transmission
peak-cut power,
the improving power value calculating unit is configured to calculate a charge
improving power value defined as a power value that increases as the charging rate of the
secondary battery becomes lower than the target charging rate of the secondary battery,
and
the charging rate improving unit is configured to, in a case that the regenerative
power is smaller than or transmission peak-cut power, have the secondary battery
charged at a power rate that is smaller than or equal to the charge improving power value
calculated by the improving power value calculating unit.
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6. The charge and discharge control device according to claim 5, wherein the peak
cutting unit is configured to have the secondary battery charged at a power rate equal to
the charge improving power value, in a case that the regenerative power is larger than or
equal to the transmission peak-cut power, and the charge improving power value is larger
than or equal to a difference between the regenerative power and the transmission
peak-cut power.
7. The charge and discharge control device according to claim 5 or 6, wherein the
peak cutting unit is configured to have the secondary battery charged at a power rate that
is smaller than a maximum charge power value for charge allowed by the secondary
battery.
8. The charge and discharge control device according to any one of claims 5 to 7,
further comprising:
a charge terminating unit configured to terminate charge by the peak cutting unit
in a case that the charging rate of the secondary battery exceeds a maximum charging rate
allowed to the secondary battery.
9. A charge and discharge control device configured to control charge and
discharge of a secondary battery coupled to a load capable of generating a regenerative
power, the charge and discharge control device comprising:
a peak cutting unit configured to, in a case that a regenerative power generated
by the load is larger than or equal to a transmission peak-cut power set as a power
transmittable to a wire, have the secondary battery charged at a power rate that is larger
or equal to a difference between the regenerative power and the transmission peak-cut
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power;
an improving power value calculating unit configured to calculate a charge
improving power value defined as a power value that increases as a charging rate of the
secondary battery becomes smaller than a target charging rate; and
a charging rate improving unit configured to, in a case that the regenerative
power is smaller than or equal to the transmission peak-cut power, have the secondary
battery charged at a power rate that is smaller than or equal to the charge improving
power value calculated by the improving power value calculating unit.
10. The charge and discharge control device according to claim 9, wherein the peak
cutting unit is configured to have the secondary battery charged at a power rate equal to
the charge improving power value, in a case that the regenerative power is larger than or
equal to the transmission peak-cut power, and the charge improving power value is larger
than or equal to a value of a difference between the regenerative power and the
transmission peak-cut power.
11. A charge and discharge control method using a charge and discharge control
device configured to control charge and discharge of a secondary battery coupled to a
load capable of generating a regenerative power, the charge and discharge control method
comprising:
in a case that a required power required by the load is larger than or equal to a
reception peak-cut power set as a power receivable from a wire, a peak cutting unit
having the secondary battery discharged at a power rate that is larger or equal to a
difference between the required power and the reception peak-cut power;
an improving power value calculating unit calculating a discharge improving
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power value defined as a power value that increases as a charging rate of the secondary
battery becomes larger than a target charging rate; and
in a case that the required power is smaller than or equal to the reception
peak-cut power, a charging rate improving unit having the secondary battery discharged
at a power rate that is smaller than or equal to the discharge improving power value
calculated by the improving power value calculating unit.
12. A charge and discharge control method using a charge and discharge control
device configured to control charge and discharge of a secondary battery coupled to a
load capable of generating a regenerative power, the charge and discharge control device
comprising:
in a case that a regenerative power generated by the load is larger than or equal
to a transmission peak-cut power set as a power transmittable to a wire, a peak cutting
unit having the secondary battery charged at a power rate that is larger or equal to a
difference between the regenerative power and the transmission peak-cut power;
an improving power value calculating unit calculating a charge improving power
value defined as a power value that increases as a charging rate of the secondary battery
becomes smaller than a target charging rate; and
in a case that the regenerative power is smaller than or equal to the transmission
peak-cut power, a charging rate improving unit having the secondary battery charged at a
power rate that is smaller than or equal to the charge improving power value calculated
by the improving power value calculating unit.
13. A program to cause a charge and discharge control device configured to control
charge and discharge of a secondary battery coupled to a load capable of generating a
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regenerative power, to function as:
a peak cutting unit configured to, in a case that a required power required by the
load is larger than or equal to a reception peak-cut power set as a power receivable from
a wire, have the secondary battery discharged at a power rate that is larger or equal to a
difference between the required power and the reception peak-cut power;
an improving power value calculating unit configured to calculate a discharge
improving power value defined as a power value that increases as a charging rate of the
secondary battery becomes larger than a target charging rate; and
a charging rate improving unit configured to, in a case that the required power is
smaller than or equal to the reception peak-cut power, have the secondary battery
discharged at a power rate that is smaller than or equal to the discharge improving power
value calculated by the improving power value calculating unit.
14. A program to cause a charge and discharge control device configured to control
charge and discharge of a secondary battery coupled to a load capable of generating a
regenerative power, to function as:
a peak cutting unit configured to, in a case that a regenerative power generated
by the load is larger than or equal to a transmission peak-cut power set as a power
transmittable to a wire, have the secondary battery charged at a power rate that is larger
or equal to a difference between the regenerative power and the transmission peak-cut
power;
an improving power value calculating unit configured to calculate a charge
improving power value defined as a power value that increases as a charging rate of the
secondary battery becomes smaller than a target charging rate; and
a charging rate improving unit configured to, in a case that the regenerative
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power is smaller than or equal to the transmission peak-cut power, have the secondary
battery charged at a power rate that is smaller than or equal to the charge improving
power value calculated by the improving power value calculating unit.