FORM 2
THE PATENTS ACT 1970
(39 of 1970)
AND
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rulel3)
1. TITLE OF THE INVENTION:
"AN EFFICIENT ENERGY MANAGEMENT SYSTEM"
2. APPLICANT:
(a) NAME: KPIT CUMMINS INFOSYSTEMS LIMITED
(b)NATIONALITY: Indian Company incorporated under the Companies Act, 1956
(c) ADDRESS: 35 & 36 Rajiv Gandhi Infotech Park, Phase 1, MIDC, Hinjewadi, Pune - 411057, Maharashtra, India.
3. PREAMBLE TO THE DESCRIPTION:
The following specification describes the invention and the manner in which it is to be performed.

Technical Field:
The invention generally relates to an energy management system for efficient/optimal utilization of energy storage devices and more specifically relates to a control circuit which provides a switching logic to ensure efficient utilization of the energy storage devices.
Background and Prior Art:
A hybrid vehicle utilizes a combination of two or more distinct power sources like fuel and electricity, and an electric vehicle utilizes electric motors for propulsion. As such, hybrid and electric vehicles are equipped with various energy storage devices like battery, supercapacitor, fuel cells, etc. With a combination of energy storage devices being utilized, it is important to ensure efficient flow of energy and optimal transfer of energy between the various energy storage devices. The energy storage devices store the charge/energy when they are charged. During the discharge of the storage device, the stored energy is released and the released energy is utilized for performing various activities.
Vehicles, when in the cruise mode, do not typically use electrical energy. On the other hand, electrical energy generated due to the rotating motor under a mechanical coupling can be utilized. This energy is otherwise, if not tapped, simply dissipated into the atmosphere. Tapping this energy to perform the work of the battery for a few extra cycles or for recharging the battery helps in increasing the efficiency by regeneration. This regeneration energy exhibits a large variation in current and voltage over time. It is characterized by current surges. Feeding such electric power to the battery while recharging would reduce the life of the battery. Hence, battery charging on the fly is not advisable. An alternative would be to charge a super capacitor (SC) during this regeneration mode. The super capacitors that can source and/or sink virtually any amount of current, under a voltage limitation, are best suited for the purpose. This is because they can be charged or discharged a great many times without undergoing performance deterioration. They avoid subjecting the batteries to sudden charging or discharging, increasing their lifetime, while fulfilling the purpose of efficiency enhancement. Moreover, regeneration of energy, which would otherwise be useful only when batteries

are in a discharged state, would take place through the SC even when the battery is fully charged.
The input voltage applied to charge the energy storage devices in a vehicle varies based on various parameters. Additionally, the voltage generated from the regenerative braking used to charge the energy storage devices varies over a range of voltages due to different reasons. Furthermore, for example, to charge a 50V battery from a supercapacitor, the supercapacitor voltage needs to be higher than 50V, which places cost and size constraints on the design. Also, a major portion of the energy stored in the supercapacitor cannot be transferred to the battery, because the battery voltage will be no lower than 40-45V.
Thus, to ensure efficient utilization of the energy storage devices, the devices should be charged to their maximum ratings, irrespective of the variable input voltage ranges. Additionally, the energy storage devices should also not be over charged or undercharged. Furthermore, the energy loss due to self-discharging, leakage and various other reasons should be minimal.
The voltage limitation of the super capacitors must be overcome by making their configuration controllable. That is, when more voltage is required than the maximum voltage of the supercapacitors, more of these devices in series will be able to provide it. In addition, depending on the actual voltage generated across the motor-generator, the configuration of the supercapacitors has to be decided.
Summary of the invention:
An object of the invention is to provide an energy management system for efficient/optimal utilization of the energy storage devices in various applications like a hybrid vehicle, an electric vehicle, machineries, and similar other applications utilizing various energy storage devices. The method of the present invention utilizes a switching circuitry matrix for providing switching between various series parallel combination of the plurality of supercapacitors and batteries being used in a vehicle.

Another object of the invention is to provide the energy management system for efficient/optimal utilization of the energy storage devices by charging them to their maximum rating irrespective of the variable input voltage range, avoiding overcharging or undercharging of the energy storage devices and reducing the energy losses due to self discharging, leakage and various other reasons.
A further object of the invention is to ensure efficient/optimal utilization of the supercapacitors to the charge the batteries with reduced cost and size constraints on the design.
Brief Description of the drawings:
FIG 1 illustrates a block diagram of a control circuit for charging and discharging
FIG 2 illustrates supercapacitors charging and discharging modes.
FIG 3 illustrates a state diagram of supercapacitors modes.
FIG 4 illustrates primary electric components.
FIG 5 illustrates charging profile of three different supercapacitors values.
FIG 6 illustrates partially charged supercapacitor switched into different configurations.
FIG 7 illustrates possible electric configuration of 8 capacitors.
FIG 8 illustrates control circuit block diagram in which microcontroller is used
FIG 9 illustrates the switch matrix used to modify supercapacitor configuration.
Detailed Description:
In accordance with the above objectives, the present invention provides an energy management system, for efficient/optimal utilization of multiple energy storage devices used in various applications like an electric vehicle, hybrid vehicle, machineries, etc. More specifically, the present invention discloses an efficient energy management system in a vehicle, comprising a switching circuitry matrix having plurality of charging-discharging switches; at least one rechargeable powering device which is enabled to power said hybrid vehicle; at least one energy storage device which is enabled to store and release energy during regenerative braking; a means connected to wheels of said hybrid vehicles and used to charge said energy storage device during regenerative braking; at least one voltage regulator which is enabled to provide regulated voltage, as required.. The switching circuitry matrix, under control of the control logic, is utilized to

provide dynamic reconfiguration of said energy storage devices according to the need, to recharge the plurality of powering devices, to decide/monitor energy requirements of the means connected to wheels, to provide connection between rechargeable powering device, means connected to wheels & energy storage devices during normal running operation or regenerative braking, enabling optimal utilization of said energy storage devices. The said dynamic reconfiguration of the energy storage devices by the switching circuitry under the control of the control logic comprises arranging the plurality of energy storage devices in a series arrangement or a parallel arrangement or a combination of a series and parallel arrangement, as per the requirement.
In a preferred embodiment, a method of reconfiguring energy storage devices, preferably supercapacitors, for maximum usable energy transfers is disclosed. A hybrid electric vehicle or electric vehicle having regeneration capability, i.e. vehicle which can convert the kinetic energy back into electrical form while braking, so that the kinetic energy can be reused is taken into consideration. Referring to FIG. 4, the primary electric components are shown. The main elements are the powering device, preferably battery (46), the motor/generator (41) that is connected to the wheels and provides acceleration / braking, and the supercapacitor (42). A triple switch (43, 44, 45) is required for interconnecting these elements, due to the multiple required configurations. The battery and the motor/generator are connected through switch (44); the supercapacitor and the motor-generator are connected through switch (43); whereas the battery and the capacitor are connected through switch (45). Only one switch would be ON at a time during normal operation, though it is possible to have modes in which the motor (41) is driven by the battery (46) and the supercapacitor (42) simultaneously, if they are electrically equalized, or the battery (46) and the supercapacitor (42) are simultaneously charged by the generator (41). Such modes may be required in case of an extreme demand for charge by the motor (41), or in case of an extreme supply of charge from the generator (41). However, the equalization requirement imposes increased cost, complexity, and inefficiency, making it less likely that such modes will be used in normal operation. In preferred embodiment, only simpler modes, where only two of the three elements are connected together at any time, are considered.
Referring to Graph 1 below, the normal operating ranges of the three key elements is shown. The battery and motor/generator are typically designed to operate within a narrow

range, say 42-48V. (Other similar narrow ranges are also popularly used in vehicles of different capacities, e.g. 10-12V, 20-24V, 66-72V, etc.) The battery operating range depends on battery technology and design. The motor operating range also depends upon the motor design. It should be noted that the values are exemplary only and motors and batteries with wider operating voltage ranges are also possible. A capacitor can normally span the entire voltage range from 0V to its rated voltage. Generally, supercapacitors have a higher minimum voltage limit for reliable operation. The key point is that each of the three elements, the battery, the motor and the SC may have a different optimal operating range. Currently, the common practice for prevalent designs is to operate the battery and motor in a narrow, common range, such as 42-48V. In the present invention, this range is termed as the voltage operating range.

Referring to FIG 5 charging profiles of three different capacitors of values C, C/2, and C/5, all superimposed on the preferred operating range of 42-48V in our example, are seen. From the profiles, it is seen that a high charge of Q1 stored on C may bring its voltage to about 45V. A medium charge Q2 stored on C may bring its voltage to about 20V, and a small charge Q3 may bring its voltage to about 8V.
A regeneration mode in an EV or a hybrid vehicle, wherein kinetic energy is converted to electricity and stored in the capacitor C is taken as an example. It may be appreciated that the amount of such stored energy depends upon the vehicle operating condition, such as speed and amount of braking applied. High amount of regeneration, which is possible in rapid slowdown from a high initial speed, may lead to generation of a high amount of charge such as Q1. Low amount of regeneration, which is possible in gentle slowdown,

may lead to generation of a small amount of charge such as Q3. The supercapacitor will be charged to 45V and 8V respectively, by storing the charge in it, assuming that supercapacitor was initially completely discharged.
If the supercapacitor is charged to 45V, it falls in the voltage operating range, and may be used either to charge the battery or to drive the motor, whenever necessary. However, if the supercapacitor is charged to 8V, then it is not in a "useful" state. Enough additional charge must be stored in supercapacitor to bring its voltage up into the voltage operating range in which case it will be used to charge the battery or to drive the motor. Once it discharges down to 42V, it may not be used any more until it is charged up again. This restriction effectively renders 80-90% of the charge stored in supercapacitor unusable for the purpose of charging the battery or driving the motor.
If we know that only a small amount of charge, Q3, will be generated, then we would be better off using a smaller C/5 capacitor. It would be charged to the voltage operating range, and be usable. Similarly., for a medium amount of charge, Q2, a C/2 capacitor would be better instead of either C or C/5.
Therefore, a dynamically configurable capacitor that can take a range of different values can be added. A suitable supercapacitor value can be selected depending on the accumulated charge and expected additional charge to be stored. Due to this, the supercapacitor can be always kept in or close to the voltage operating range. A larger portion of the charge stored on the supercapacitor is now usable. A partially charged supercapacitor may be switched into a different configuration, thus changing its voltage and charge-acceptance capacity. Such a concept is depicted in FIG 6. Several smaller capacitors can be included, adding up to a total value of supercapacitor, interconnected by a switching circuitry matrix. The dynamic reconfiguration of the capacitor is allowed by the switching circuitry matrix, under control of control logic. Possible mechanisms for the switching circuitry matrix have been described elsewhere in the document. The control logic has various inputs, including, but not limited to, mode, vehicle speed, acceleration / deceleration, expected charge regenerated, derived from a suitable predictive algorithm, present charge and voltage on each of the supercapacitors and the battery, and states of

the switches. Depending upon the switching circuitry matrix state, an equivalent capacitance 'Ceq' is presented by the complete system to the rest of the system.
FIG 7 refers some possible electrical configurations of eight capacitors that can be achieved by a suitable switching circuitry matrix design, A unique equivalent capacitance is presented by each configuration. It may be appreciated that many possible configurations exist. It is also possible to make the capacitance values unequal to achieve a wider range of options. A final design may implement a limited set of options, based on system design considerations, desired efficiency, cost, etc. The Graph 2 below shows possible ratios achieved using 12 of the possible configurations using eight equal-sized capacitors. It also refers ratios of possible values to the maximum possible capacitance using the capacitors.

The Graph 3 below refers the charging profile of such a dynamically configurable supercapacitor bank. The X-axis represents time. The Y-axis represents all quantities expressed in percentage, as compared to their maximum values. A uniform rate of charging is assumed, as indicated by the "charge" line. The equivalent capacitance normalized to the maximum value is presented by the "cap_ncnn" line. The supercapacitor is assumed to be fully discharged at the start. Initially, the lowest effective capacitance value is selected by the configuration logic. As the stored charge increases,

the voltage quickly shoots towards the maximum 100% value. The configuration is then changed to the next higher capacitance value available. The voltage immediately drops as a result, since the charge is conserved. As the charging continues, the voltage starts to rise again. This happens several times, until at 25% charge, the configuration changes for the last time and the maximum value of the capacitance is selected.

If the capacitance were to be fixed and not reconfigurable, then it would always be set to the 100% level, and its voltage would follow the same linear profile as the charge, it would be within the 90% to 100% voltage range only at the end of the charge cycle. However, the reconfigurable capacitance reaches the 90% level even at low charge levels (between 5-25%). This demonstrates the utility of the reconfigurable capacitance.
Similarly as a discharging supercapacitor discharges from 100%, a fixed supercapacitor would soon drop below the voltage operating range and have to be disconnected. A suitably reconfigurable supercapacitor, however, could continue to be used by reducing the capacitance and increasing the voltage into the voltage operating range. A well-designed scheme can manage to use up much more of the available charge, significantly increasing the utility and efficiency of the system.

In another embodiment, the circuit that uses supercapacitors for energy storage purpose is disclosed. FIG 1 refers to the block diagram of the control circuit for charge and discharge of super capacitor. The supercapacitors (15) can be charged using motor (14) acting as generator or through other external power sources (11). Rating of supercapacitor may not be same as the generated voltage; instead it will be much higher when smaller capacitors are used. In addition, super capacitor should not be charged beyond some fixed voltage and should not be discharged below some fixed voltage. Hence, voltage across the circuit is regulated by a regulator circuit (12) to protect it from exposure to very high voltage. The supercapacitor is connected or disconnected from charge or discharge path based on its voltage by switching circuitry matrix (16). Different connection configurations such as generator charging super capacitors (15), battery (13) driving motor (14), motor (14) driven by other external power source (11) and so on, are allowed by switching circuitry matrix (16).
FIG 2 refers to the supercapacitor charging and discharging states. There are three states in the FIG 2. FIG. 3 refers to the corresponding state diagram.
STATE 1: It is the initial state. In the initial state 'C-Init' motor is connected to battery. (VACC>0).
STATE2: When, motor is in regenerative mode (VACC is zero) C1 (Condition 1) takes place, STATE 1 —► STATE2 transition will happen. In addition, super capacitors will get charged from generated voltage.
STATE3: When the capacitors are charged up to or greater than 24 Volts, the C2
(Condition 2) occurs. We can manually change the STATE 2 —► STATE3 for rotating
motor using super capacitor instead of battery.
(VACC > 0).
Wherein,
VACC: It is the accelerator voltage.

Operation of states is explained below. FIG 3 shows the state diagram of regenerative braking. Refer Table 1 for state and condition and refer Table 2 for the status of operating states and switches and LEDs.
Operation of states
STATE3 —►STATE1:
Condition: In this state switch SW1 is in ON position until VACC > 0 Volts and remaining all switches are in OFF position.
Operation: Motor will be rotating using 24V DC supply from the battery through switch SWI (ON) and C (Battery to motor Controller).
STATE 1 —► STATE2:
Condition: In this state switch CSW2 is in ON position, switch Sel_SW4 is in ON
position, PSW5 to PSW12 are in ON position (Super capacitors (SC) are connected in
parallel) and remaining all switches are in OFF position.
Operation: Motor will be working as a DC Generator. Generated voltage charges the
Super capacitors (SC), which are connected in parallel, until the voltage across the Super
Capacitor (Vsc) reach 6 Volts through switch CSW2 and Sel_SW4.
STATE 2 —►STATE3:
Condition: In this state switches SSW13 to SSW16 are in ON position (Super capacitors
(SC) are connected in series), switch DSW3 is in ON position until voltage across the
Super Capacitor (Vsc) is grater then 24 Volts and remaining all switches are in OFF
position.
Operation: Motor will be rotating using Super Capacitor voltage (maximum 30V DC)
through switch DSW3 and C (Battery to motor Controller).
The Table 1 and Table 2 below show various operating states and status of switches and LEDs during respective operation.

State Condition
S1 C Init l. SW1 = ON
S3→ S 1 2 CSW2 = OFF
Motor rotates through 3, Sel_S\V4 = OFF
Battery {24VDC) supply. 4.
6.
7.
8. DSW3 = OFF VACc > 0 volts 1.ED1 = OFF LED2 = OFF
Vsc > 20 vol Is
S1 → S2 C1 1. SW1 = OFF
5 Super capacitors charging 2. CSW2 = ON
connected in parallel. Motor 3. Sel_SW4 = ON
becomes Generator, 4. 5.
6.
7. S. 9. D.SW3 = OFF
VACC < 0 volts
VSC -- 6 volts Parallet,
LED 1 = OFF
LED2 = OFF
Five Super capacitors (6V/2F) are
in parallel combination while
charging.
S2 → S3 C2 1. SWI = OFF
Motor rotates through Super 2. CSW2 = OFF
capacitor ( maximum 3. Sel_SW4 = OFF
voltage 30VDC) supply. 4. DRW3 = ON
5 Super capacitors 5. VSC > 24 volts(Series)
discharging, connected in 6. LED1 = ON→OFF
series. 7. S. LED2 = ON
Five Super capacilon (6V/2F) are in series combination while
discharging and rotating motor
Table 1: States and conditions
Table 2: Status of operating states and switches and LEDs
ST SW cs DS Sel_ PS PS PS PS PS PS PS PS SS SS SS SS

AT 1 w W SW4 w w w W w w w w W w W W16
E 2 3 5 6 7 8 9 10 11 12 13 14 15
1 ON OF OF OFF 0 0 0 0 0 OF OF OF OF OF OF OFF
F F FF FF FF FF FF F F F F F F
2 OF O OF ON O O O O O O O O OF OF OF OFF
F N F N IN N N N N N N F F F
3 OF OF O OFF O O O O O OF OF OF O O O ON
F F N FF FF FF FF FF F F F N N N

STATE LED] LED2
1 OFF OFF

2 OFF→ ON OFF

3 OFF ON


In yet another embodiment, a method of supercapacitors charging-discharging is disclosed, in which function of switching circuitry matrix is monitored by a microcontroller. Jn the implementation of energy regeneration of the hybrid and electrical (HEV) vehicle, four modes have been identified. In the first mode, the motor is driven by the battery; this is the normal mode. In the second mode, the motor rotates without an electric drive, thus acting as a generator, with the ability to charge the supercapacitors. This is when the vehicle is in the cruise mode. The third mode is the discharging of the supercapacitors through the motor, where the supercapacitors assembly simply replaces the battery until it is fully discharged. The fourth mode identified is the discharging of the supercapacitors to recharge the battery, which can be done at the battery's specified rate.
Due to cost considerations, individual supercapacitors voltage rating is low. Hence, to increase the voltage to which they can be subjected to while charging, several supercapacitors are to be connected in series. The number will depend on the amount of regeneration energy available, which depends directly on the rotation of the motor. The speed and the voltage generated are linearly related. If the speed of the vehicles is high, either more supercapacitors in series or a supercapacitor of a higher rating which is able to handle the high voltage generated can be used. When the supercapacitors are to be discharged, again the low voltage limitation is to be overcome by combining them in series. This is because driving the motor or charging the battery requires a considerable voltage as compared to the supercapacitors' rated voltage (as of this generation SCs). Thus, since several supercapacitors that are already charged to certain minimum value are required in these modes in the charging period, adequate redundancy must be maintained. This is done by placing multiple required supercapacitors configurations meaning either a single supercapacitor of required denomination or a few supercapacitors of lesser denomination in series, as described above in parallel. Appropriate control involves the following steps recursively: (1) Monitoring:
a) Detection of the motor's status, whether it's acting as a motor or generator, and the voltage across the motor
b) Detection of the voltages across each and every supercapacitor so as to check whether it is in the proper voltage bracket
c) Detection of the battery voltage

(2) Decision-making:
a) Deciding on the current mode
b) Deciding which SC must be used and in what configuration
(3) Processing/Taking actions:
a) Making the circuit connections
b) Switching the SC into the required configuration
All these tasks require constant monitoring and switching. The number of switches depends on the number of supercapacitors and the number of configurations allowed. In a complex system, it is not possible to switch manually between battery and supercapacitors. An intelligent device is a necessity. Thus, a microcontroller or similar other device may be used.
Circuit details of present embodiment:
FIG 8 shows the control circuit block diagram that implements the control logic for dynamic reconfiguration of the energy storage devices of the present invention. Microcontroller (83) of the control circuit has specified operating (maximum analog input) voltage range. This means that all voltages are needed to be scaled down to this range. Potential divider arrangements (81) are provided for the same. The scaled-down voltages are given to buffers to isolate the microcontroller (83) and switching circuitry matrix (85).
At the output side, the available output voltages again are Vmax or 0 V corresponding to a digital 1 or 0. These are to be used to drive the switching circuitry matrix (85). Amplification is necessary and is provided by any amplifier, example, amplifier ICs ULN2803- a Darlington pair array, which ramped up the power.
The choice of the switching elements of the switching circuitry matrix (85) is to be made between power MOSFETs and relays. Power MOSFETs have a superior performance as their switching times are in nanoseconds. However, a combination of nMOS and pMOS type of power MOSFETs may be required and the generation of their gate voltages would have been too complex for the application. On the other hand, relays, though bulky, provide complete isolation. They can only switch slowly. However, at the cutoff

neighborhoods of the supercapacitors voltages, the charging or discharging rates are not high and the small delay (in milliseconds) between the approaching of threshold and the actual switching does not cause over charging or discharging. Hence, relays may be preferred. However, it is to be understood that the use of relay as the switching elements is only exemplary. It is to be noted that the switching elements are not to be limited only to MOSFETs and/or relays, but any other similar elements may be used as the switching elements, as per the requirement.
Implementation
If the entire system is viewed as a state machine, then the next state or mode of the system can be determined by monitoring the inputs and carrying out logical processing on the values obtained. The process and the four modes have been outlined below:

Referring to the process above, if the motor is in the motor mode, then Mode 1 is the current state.
As the motor goes into the generator mode and if the supercapacitors are not fully charged, Mode 2 is invoked. When motor goes into motor mode again, and the supercapacitors are not discharged down to the minimum threshold, Mode 3 is invoked, where the acceleration of the vehicle derives electrical energy from the corresponding supercapacitor assembly. Once the supercapacitor are discharged, the battery provides the current (Mode 1 again) and they become available for the next charging cycle. If the battery voltage falls below a certain minimum value and the supercapacitors still have some amount of charge, Mode 4 is invoked. Otherwise, the process must be suspended and the battery must be taken out for external recharging. With the energy regeneration

according to the embodiment of the present invention, it will be observed that the number of times external recharging needs to be done would be reduced due to the usage of the energy recovered. Moreover, indicative outputs, such as blinking of LEDs, or similar other outputs, may be provided for easy detection of the mode and indication of whether the supercapacitors are fully charged or discharged.
A microcontroller that can monitor all the circuit voltages and take the requisite control actions is required. This means that the choice of the microcontroller is dominated by the availability of a large number of analog ports, an inbuilt analog to digital convertor, a large number of output ports, enough speed, and enough memory. Any such suitable microcontroller or processor may be used. The battery that drove the motor should also supply power to the integrated circuits.
The switching circuitry matrix used to modify supercapacitor configurations is shown in FIG 9. The main switches, S1 to S4, provide the connection between the battery / motor / supercapacitors assemblies. Only one of them is ON at a time. In mode 1, switch SI is ON, and so on.
Considering an example, the supercapacitors,, are of 6V rating; whereas the battery is of 24V. During battery charging, the input must be 28V. Hence, five supercapacitors each charged to 6V suffice. The switching between the "supercapacitors-in-series assembly" and the "supercapacitors-in-parallel assembly" is done by using the switches S9 to S12, all of which when ON, make the supercapacitors in series and the switches Sp5 to Sp8 and Sp13 to Spl6, all of which when on, make the supercapacitors in parallel.
For example, the vehicle runs on the battery when the battery is ON, connected to the motor and when the bike is accelerated. The signal from the accelerator is modulated depending on the position (rotation of the accelerator handle) and the speed can thus be varied. When the vehicle is accelerated, the setup is in normal mode. When the vehicle is in regeneration mode, the motor acts as a generator (rotating on mechanical power and not the battery power). This is mode 2, in which, the switches Sp5 to Sp8 and Sp13 to Spl6 are made ON and S9 to S12 are OFF. In mode 3, the supercapacitors are connected to the motor and not the battery. The supercapacitors are brought into series and they can

be discharged down to the minimum voltage threshold. In mode 4, the supercapacitors are in series, but connected to the battery charger instead of the motor.
Multiple checkpoints or indications may be incorporated to make the debugging easier. These may be provided by means of LEDs, which would indicate the mode, whether the discharging should be stopped, whether the charging should be stopped, an LED acting as alarm, etc.
In yet another embodiment, a method of reconfiguring batteries for optimal usable energy transfer is disclosed. It also explains another method to utilize the charge stored in supercapacitor efficiently by charging low rating batteries for further usage. For example, one of the applications of such a system is to provide a low-cost system with a 3 V super capacitor, for a bank of 25, 2.1V batteries in an automotive application, and a connection circuit, for regenerative braking. By using super capacitor, low volt rating cells are charged and the switching circuitry matrix according to the earlier embodiment of the present invention arranges the cells in series to get the higher voltage. The switching circuitry matrix is used to switch from first cell to second cell, once the first cell is fully charged. Similarly, it switches to third cell once the second cell is in fully charged state. However, the circuit checks whether the first cell is still in the full state of charge or not before switching happens. This is the self-monitoring method. In case it is not in full charge state, it continues charging the current cell. The switching circuit charges the low voltage cells and series connection of such low rating cells can provide higher voltage that can be utilized to provide supply power to the motor. First step is to connect the first battery to supercapacitor and check the voltage of battery. When voltage of battery reaches to 2.1 V, (using the super capacitor of 3 volts) first battery disconnects and second battery connects for charging. While charging the second battery, voltage across the first battery is checked and if the battery voltage goes down below full voltage, it is charged again. Once the battery voltage sets to 2.1 volts, then it switches to charge the second battery.
Another method is the settling time method. The method is to charge the battery until the settling time. For the present example, it required to set the battery at 2.1 volts, so that it will not self-discharge below 2.1 volts. Once all the 25 batteries are charged, then they are

connected in series to get the effective output voltage of 50 volts. Switching circuitry
control of the present invention is used to connect the batteries in series.
Example: System Design considerations for charging 25 lead acid batteries using single
super capacitor
Assumptions
Input supply voltage regenerated voltage from vehicle - 50-60 V DC, 200A
Supply voltage available for the time interval: 20 sec
Super capacitor is charges with 200 A current with regulation for an interval of 20 sec.
Super capacitor voltage - V sc = 3 voits (Capacitance = 1500F)
Given time is dt = 20 sec
d1= dQ / dt [ 1 ]
dQ = d1 x dt
= 200 A x 20 sec = 4000 coulomb
Q = C X V 2]
C = Q/V
= 4000/3
= 1333.33 F C =1500 F C (calculated) = 1500 F
Charging of supercapacitor
Thus, by using a super capacitor of 3 volts, 1500F, we can charge 25 cells of low volt of 2.1 and arrange them in series to get 50 volts.


A high level block diagram of super capacitor charging is illustrated above. The input regenerated voltage is in the range of 50-60 volts, 200A. The charging super capacitor is of 3 volts, 1500F. The voltage regulation block regulates the voltage at 3.7 volts to charge the super capacitor.

Charging of lead acid battery
Charging of lead acid battery from super capacitor is illustrated above. The lead acid
battery used to charge is of 2.1 volts. The super capacitor is charged at 3 volts. The
charging of battery through super capacitor is controlled by controlling circuit of constant
voltage and constant current.

Charging 25 batteris and connect them in series after fully charged Charging of batteries using the switching circuitry matrix through super capacitor is illustrated above. The switching circuitry matrix may be manually controlled or controlled through hardware or microcontroller controlled, as illustrated in the earlier

embodiments. The switching circuitry matrix monitors battery voltage of each battery one by one. Initially, the switching circuitry matrix charges the first battery in line. The switching circuitry matrix charges and monitors the first battery until its full voltage is reached. Then the charging path for the first battery is disconnected while the charging path for the second battery is established. In the self-monitoring method, while charging the second battery, the switching circuitry matrix monitors voltage across the first battery. If the voltage of the first battery drops below the full voltage, then the first battery is charged again to its full voltage and then the second battery is charged. Once all batteries are charged to their full voltage, the control circuit will combine the batteries in series. In this method, self-monitoring by the switching circuitry matrix is observed as it checks back onto the voltage of the previous battery. The switching circuitry matrix can be used to charge any battery to its full (or lower) voltage, which is lower than super capacitor voltage. Take the example of 25 batteries, each of 2.1 volts through super capacitor. One of the approaches is to charge the single battery. The switching circuitry matrix monitors the first battery. The switching circuitry matrix checks if the voltage of battery is reached to 2.1 Volt, disconnects the charging path of the first battery, and then connects the second battery for charging. While charging the second battery, it will check the voltage across the first battery. If the battery voltage goes down, then again charge the first battery. Once the battery voltage sets to 2.1 volts, then charge the second battery. A second approach utilizes the settling method. In this method, the switching circuitry matrix charges the first battery till it's settling time so that the battery does not self-discharge below the full voltage. In this approach, the switching circuitry matrix does not monitor the previous battery once it moves on to the next battery. The switching circuitry matrix charges all the batteries one by one till their settling time. For example, the switching circuitry matrix charges the first battery till the settling time. It is required to set at 2.1 volts, so that it will not self-discharge below 2.IvoIts. Once the all 25 batteries are charged, by either method, they are connected in series to get the effective output voltage of 50 volts. The switching circuitry matrix is used to connect the batteries in series.
The above examples, which includes preferred embodiment, will serve to illustrate the practice of this invention being understood that the particular shown by way of example, for purpose of illustrative discussion of preferred embodiment of the invention and are not limiting the scope of the invention.

We claim,
1. An efficient energy management system, comprising:
a) a switching circuitry matrix having plurality of charging-discharging switches;
b) at least one powering device
c) at least one energy storage devices enabled to store and/or release energy during regeneration;
d) a means used to charge said energy storage device during regeneration;
e) at least one voltage regulator enabled to provide regulated voltage;
wherein, said switching circuitry matrix under control of control logic, being utilised to provide dynamic reconfiguration of said energy storage devices and the said powering device according to the need, to recharge the plurality of powering devices, to decide/monitor energy requirements of the means used to charge during regeneration, to provide connection between rechargeable powering device, means used to charge during regeneration and energy storage devices during normal running operation or regeneration, enabling optimal utilization of said energy storage devices and the said powering device.
2. An energy management system as claimed in claim 1, wherein the said dynamic reconfiguration of the said energy storage devices and the said powering device comprises arranging the plurality of energy storage devices and the said powering device in a series arrangement or parallel arrangement or a combination of a series and parallel arrangement, by the said switching circuitry matrix under control of said control logic, to ensure optimal energy transfer and utilization.
3. An energy management system as claimed in claim 1, wherein said control logic comprises various inputs including mode, speed, acceleration, deceleration, expected charge regenerated, present charge and voltage on each of the energy storage devices and the powering device and states of the switches.
4. An energy management system as claimed in claim 1, wherein said control logic observes either self-monitoring method or a settling time method.

5. An energy management system as claimed in claim 1, wherein said powering device is a rechargeable or a non-rechargeable power source.
6. An energy management system as claimed in claim 1, wherein sard energy storage devices are plurality of supercapacitors.
7. An energy management system as claimed in claim 1, wherein said means used to charge the said energy storage devices is a motor or generator.
8. An energy management system as claimed in claim I, wherein a generated voltage in said system is converted into a regulated voltage by said voltage regulator.
9. An energy management system as claimed in claim 1, wherein said charging-discharging switches comprises plurality of electronic as well as electromechanical switches.
10. An energy management system as claimed in claim 1 and claim 6, wherein said mechanical as well as electromechanical charging-discharging switches are controlled by said switching circuitry matrix.
1 ]. An energy management system as claimed in claim 8, wherein said mechanical as well as electromechanical charging-discharging switches are optionally controlled by microcontroller.
12. An energy management system as claimed in claim I, wherein said switching circuitry matrix monitors the charging and discharging of said powering device and the said plurality of energy storage devices.
13. A method for efficiently utilizing the energy management system as claimed in claim 1 comprising:
a) monitoring energy requirement status of the means connected to wheels, voltage across said plurality of energy storage devices and the powering device;

b) determining required mode and configuration of said plurality of energy storage devices and the powering device based on step a); and
c) implementing circuit connections via switching circuitry matrix into required configuration of said plurality of powering devices and plurality of energy storage devices based on step b).

14. The method according to claim 13, wherein, said means used to charge the said energy storage devices is a motor or generator.
15. The method according to claim 13, wherein, said energy storage devices are plurality of supercapacitors.
16. The method according to claim 13, wherein, said powering device is a rechargeable power source.