1. A power supply circuit comprising: a first series regulator including a first semiconductor elernelit and a first constant voltage source; arid 5 a second series regulator includirig a second semicot~ductore lement and a second constant voltage source, wherein tile first series regulator and tlie second series regulator are cascaded and an input voltage to the first series regulator is a high voltage equal to or greater than 500 V. 10

2. The po\ver supply circuit accordit~gto claitii I, wherein the first se~niconductor element atid the second semiconductor elemelit each include an input electrode, an output electrode, acid a control electrode, and 16 wherein the first constant voltage source and the seco~~codn stant voltage soorce are co~i~~ecttoe dth e control electrode of the first semiconductor element and the control electrode of the seco~ids e~i~ico~iducetloelrl lent, respectively.

3. Tlie power supply circuit according to claim 1, -, 20 \vl~erein a detectioii unit configt~red to detect a value of at least otie of tlie input voltage and the output voltage is provided, and \\,herein, when tlie detection unit detects that the value is greater than a reference value, at least one of the first collstaot voltage sotrrce and the second co~lstatitv oltage soorce is co~~trollead~ itla t least one of the first semico~id~~ctor 25 elelllent and the seco~ids emicondoctor elenlent is turned off.

4. ?'lie power supply circ~~aictc ording to claim I, wherein s\vitches configaretl to vary voltage \,slues by tlie first constant voltage source and tlie second constant voltage source are provided. 30

5. Tlie po\trer snpply circuit accordi~lgto claim 4, \\,lierein tlie switch changes tlie ~'oltagcv alue in a tempol.al direction.

6. The power supply circuit according to claim I, wlierein a capacitor is providcd in parallel to each of the first consta~itv oltaxe source and the sccond constant voltage 5 source.

7. The power supply circuit according to claim 6, wl~erein current limitation elements are connected to the control electrode of the first semiconductor element and the control electi.ode of the second semiconductor element. 10

8. A power sc~pplys ystem comprising: an electric storage unit; a s\\,itcli elenlent configured to control chal-ging and discharging of the electric stol-age unit; 15 a control circuit configc~~etod COII~I-01 the s\\;itcIi element; and a power supply circuit configoretl to form operational power of the contl-ol cil-cuit froin a voltage of the electric storage unit. wherein thc power supl~lyc ii-cuit has a conligulation according to clai~n1 . . ~ . -. 20 9. An electl-ic storage device comprisi~ig: the po\versul~plys ystem according to claim 8, wherein tlircct-current pouter formed from an external poxver supply syste111 is l~sctla s charging p o ~ ~o~f cthre electric storage onif, and wherein output power of the electric storage unit is sc~ppliedto an electronic 25 device.

POWER SUPPLY CIRCUIT, POWER SUPPLY SYSTEM, AND ELECTRIC
STORAGE DEVICE
CROSS REFERENCE TO RELATED APPLICATlONS
5 This application clai~iisth e benefit of Japanese Priority Pateiit Applicatiotl
JP 2013-082659 filed April 11, 2013, the entire contents of which are incorporated
herein by refere~ice.
BACKGROUND
10 The present disclosure relates to a power supply circnit, a po\ver supply
system, and an electric storage device suitable for forti~inga lo\\>v oltage from a high
voltage.
There are kno\\,ti series regulators in which a voltage control semiconductor
elelllent is connected in series to a load, a constant voltage is supplied to the
15 se~niconductore lement by a constalit voltage source, and n voltage to be applied to
tlie load is constantly maintained (for csample, see JP 2003-259632A). The series
regolators call apply a constant voltage, for esaniple, even \\,lien a load varies.
SUMMARY
20 In the series regulator disclosed ill JP 2003-259632A, there is a concern tliat
at1 elenlent may break dowi~w hen a voltage difference between an ilipt~vt oltage and
an output voltage is very large. For esa~nple, in tlie case of an electric storage
system using a lithium ion secondary cell, for example, it is necessnry to fo~ma
powver supply voltage of a control circuit of a system, such as 12 V, fi0111 a high
25 voltage of liu~idreds of V or more. Sucli a large voltage difference itlay cause
b~rakdowno f an eleiiient ill tlie series regulato~a. ccording to tlie related art.
It is desirable to provide a power supply circuit, a power st~pplys ystcm, ant1
an electric storage device capable of fot.tiii~ig powver of a sufficiently low voltage
fro111 a liigh voltage.
30 According to an embodintent of the present disclosure, there is provided a
power supply circuit in which a first series regulator including a first semiconductor
elelne~lta nd a first constant voltage source and a second series regulator including a
second semiconductor element and a second constant voltage source are cascaded
and in which an input voltage to tlie first series regl~lator is a high voltage equal to or
greater than 500 V.
5 According to an e~nbodirnel~otf the present disclosure, since hvo series
regolators are cascaded, it is possible to for111 an output voltage which is a stable low
voltage fi.0111 an inpot voltage which is a high voltage.
BRIEF DESCRIPTION OF THE DRAWINGS
10 FIG. I is a block diagram used to describe an electric storage system to
\\,11ich an e~~ibodi~noef ~thiet present disclosure is applicable;
FIG. 2 is a diagram illustrating conl~ectiona ccording to a first embodiment
of the present disclos~rre;
FIG. 3 is a diagram illustrating co~~~~ecaticoconr ding to a second
15 embodiment of the present disclosure;
FIG. 4 is a block diagram illustrating an example of a11 application exa~ilple
of tlie present disclosure; and
FIG. 5 is a block diagram illostrating another example of the application
example of the present disclosc~re.
20
DETAILED DESCRIPTION OF THE EMBODIMENTS
Hereinafter, preferred e~nbodiliie~itos f the present disclosure will be
described in detail with reference to the appended drawings. Note that, in this
specificatiotl and the appended drawings, structural ele~ne~t~hatts have substacitially
25 tlie satlie fiu~ction and strclchlre are denoted with the saliie reference nu~nerals, and
repeated explanation of these stroctural elements is o~nitted.
Embodiments to be described below are specific exa~npless uitable for tlie
present disclosure and include various tech~iicallpp referred limitations. flowevel;
in the follo\ving description, the scope of the present disclosure is not limited to such
30 embodicnet~ts as long as no particular description is made to limit the presetit
disclosure.
Note that the following description will be made in the following order.
<1. First embodiment>
R. Second etnbodiment>
<3. Application examples>
5 <4. Modification exampleu

"Example of electric storage system"
As illustrated in FIG. 1, in an electric storage system, a control circuit 1 is
installed to co~ltlul power. The control circuit 1 includes a microcomputer. The
10 control circuit 1 performs management for charging managelnent, discharging
managemeat, deterioration suppression, and the like. To perform tlie manage~netlt,
information regarding voltage, current, temperatore, and the like fiom an electric
storage element s11cl1 as a battery cell is supplied as feedback signals and various
co11trol sigtlals are output. A po\ver supply voltage is supplied from a DC-DC
16 con\~crter2 to the cotltl.ol circclit I .
Althougli not ill~~strateetll,e ctric storage devices are connected to tel~llitlals
B+ and B- of the electric storage system. Whet1 a plurality of electric storage
ele~llentss uch as battery cells are used to generate a large output, the electric storage
device includes a plurality of modules. Altl1ougl1 not ill~tstrated, external power
20 feeding devices or loads are cotlnected to tenninals EB+ and EB- of the electric
storage system. A cbarging control switch Qc and a dischargi~lgc ontrol switch Qd
are connected in series behveen the terminals B+ and EB+ 011 tlie positive electrode
side.
The cllarging control s\vitch Qc is turned on when the electric storage device
25 is charged. The discharging control switch Qd is turned 011 when the electric
storage device is discl~arged. A diode Dd in the forward direction of a tlischarging
current is connected in parallel to the charging control switcll Qc and a diode Dc ill
the fol-\vard direction of a cllalgi~igc ttrrent is connected in parallel to the dischargi~~g
control switch Qd.
30 A voltage V, taken out from a cotl~iectio~plo int of the charging control
switch Qc and the dischargit,g co~ltrol s\vitch Qtl is supplied to a lligll voltage
regulator 3. In the high voltage regulator 3, a high voltage of the connection point
is input and a voltage V, to the DC-DC converter 2 is output. Tlie DC-DC
converter 2 forms operational power of the control circuit 1. The input high voltage
is a voltage having a variation of +SO0 V or more and an operational power supply
5 voltage of the control circuit 1 is, for example, +12 V.
hi tlie high voltage regulator 3, as \\rill be described below, two regulators
are cascaded. For example, the input voltage V, to tl~eli igh voltage regulator 3 is
about 800 V, a stable voltage of about 600 V is fonned from 800 V by tlie regulator
on the initial stage, and the output voltage V, of about 400 V is formed from the
10 voltage of about 600 V by tlie regolator on tlie rear stage. The power source of the
control circuit I has, for example, +I2 V, \vl1ic11 is formed frolorn the output voltage V,
by the DC-DC converter 2.
"High voltage regulator"
An embodiment of the present disclosure is applied to the liigli voltage
15 regulator 3. FIG. 2 is a diagram illustratilig connection in tlie high voltage regulator
according to a fi~set mboditne~iot f tl~cp resent disclosl~re. An input tenninal 1 I to
\vliich tlie input voltage V, is supplied is connected to a collector of a fi~st
se~nico~~ducetloerm ent, e.g., an insulated gate bipolar transistor (IGBT a bipolar
transistor in \vl~iclia n MOSFET is con~bined\ vith a gate unit) I via a resistor RILa nd
20 a resistor Rs. Tlie IGBT inclrtdes a collector serving as an input electrode, an
emitter serving as an output electrode, and a gate serving as a coritrol electrode.
The input voltage Vc is a varying direct-current voltage. The resistor RIL
and the resistor Rs are connected to litnit an input n1s11 current. A fi~sem ay be used
illstead of tlie resistor Ks. An etnbodiment of the present disclosure is suitable for
25 forming a po\ver supply voltage of tlle control circuit from the input voltage V,
wliieh is a relatively high voltage, e.g., +SO0 V or more.
A resistor Re1 and a series circuit of a plurality (m) of zener diodes Zlj to
ZI,, are installed bet\vee~a~ g round potential and tlie connection point of tlie resistor
RIL atid tlie resistor Rs. The series circuit of tlie zener diodes ZII to ZI,, is a first
30 constant voltage source. Tl~ere sistor RBIi s a bias resistor for the zelier diodes Zll
to ZI,,,. A voltage Vcl of the connection point of tile resistor RBI and tl~es eries
circuit of the Zener diodes ZII to ZI,, is supplied to tlie gate of the IGBT 1 via the
resistor RGI. Tlte resistor RGI is co~inected to prevent an excessive gate current
from flowing due to a charge accumulated in parasitic capacitance of the IGBT 1
when tlie IGBT 1 is turned off.
5 An output voltage V,i is take11 out from the emitter of the IGBT 1, as
necessary. The enlitter of the IGBT 1 is connected to a collector of an IGBT 2 that
fornis a second series regulatol: Between the gate and the emitter of tlie IGBT 1,
hvo Zener diodes Zpl atid Zp* are inserted in series in the backward direction. The
zener diodes Zpl and Zp2 are installed to prevent an excessive voltage from being
10 applied between tlie gate and the emitter of the IGBT I .
As in the first series regulatol; the second series regl~latorin cludes tlle IGBT
2 and a constant voltage source (mrliicli generates a voltage VG2) in wltich 11 Zener
diodes Z21 to 22" are connected in series. Tlie first and second series regulators are
cascaded. A load ZL is co~i~iectetdo tlte secant1 series regulator. The output
15 voltage V, is applied to tlie load ZI.. Tlie load ZL C O ~ I F S ~ O I It~oS, for example, a
circuit of the DC-DC converter 2 in FIG. 1. As in the first series regolatol; the
second series regulator includes a bias resistor RR?,a resistor RG2f or st~ppressiof~ a~
gate current, and zener diodes Zn and Zp4 for suppression of a voltage between a
gate and an elllitter in associatio~w~i th the IGBT 2.
20 Further, a switch SW2 is installetl to sl~ort-circuit the series circuit of the
zener diodes 221 to Zln included in the constant voltage source of tlie seco~id series
regi~latol: Wile11a control circnit (not illustrated) is it~stalleda nd tl~eco ntrol circuit
detects a risk that the input voltage V, may increase co~lsiderablya nd tlie IGBT 1 on
t11e initial stage may break down and short-circ~~iat ,c ontrol signal for turning on the
25 s\vitcll SW2 is generated. Wltelt tlie s\vitcli SW2 is turned on, the IGBT 2 is turned
ofi; thereb), preventing all excessive output voltage from being generated.
AII operation of tlie above-described high voltage regulator v i l be
described.
Reference signs of voltages and currents have the follo\ving values:
30 V,: a variable input voltage,
VFEI: a voltage behveen the gate and the emitter of the IGRT I,
V~EZa :v oltage behveen the gate and the emitter of the IGBT 2,
1st: a current flowing it1 the zener diodes Zll to ZI,,
Is*: a current flowing in the zener diodes Z21 to Zz,,,
11,: a load current,
5 VGI: a gate voltage of the IGBT 1,
VGZ: a gate voltage of the IGBT 2,
V ~ ItoI V zl,,,: zener voltages of Zener diodes ZIIt o ZI,,
V Z ~toI VZ~,:z eiler voltages of zener diodes 221 to Zln,,
V,: a stabilized output voltage,
10 Pi: input powel; and
Po: output power.
An input voltage is stabilized by the series regulator on the initial stage and
the output voltage VOi is generated. Since the gate voltage of the IGBT 1 is formed
by the series circuit of the zener diodes Zll to ZI,,, the following relation is
15 established:
Voi = VGI - VFEI (1).
A stabilized output voltage V, is forii~ed as follo\\~s by the second series
regulator:
V, = Va: - VOE~ (2), where
20 VGI =VZII +VZI?+ ... +Vzlrn (3), and
Voz 'Val + Vz22+ . . . + VZ?, (4).
Pi = V, x (Is1 + lez + l ~ ) (5), and
I', = V, x lL (6).
Esa~i~ploefs s pecific voltage valiies are as follows.
26 "VFI = 610 V" is set and the stabilized output voltage VV,i of the series
regulatol. on the initial stage is set as (610 - 5.5 = 605.5 V).
.'VO2 = 376 V" is set and tl~es tabilized output voltage V,i of the series
regulator on the initial stage is set as (376 - 5.5 = 370.5 V).
Accortlinglp, a voltage drop of almost about 200 V occurs in each series
30 regolator.
In the above-described first eoibodiii~ent of the present disclosure, the
following operational effects can be obtained.
When a load is light, a loss can be reduced.
_ Complicated switching control is not necessaly and a circuit configuration is
simple.
6 Protection can be realized against a dangerous abnormal voltage.
Since the IGBTs are cascaded, a loss of each IGNT can be reduced.
4. Second embodiment>
A second einbodiment of tlie present disclosl~re will be described witli
reference to FIG. 3. Differences frotn tlte above-described first embodiment will be
10 mainly described.
Added circuits and circuit elente~ttas re as follo\vs.
A control circuit 12 is installed to detect that tlte inpnt voltage V,
abnormally increases.
A series circuit of tletection resistors RR,1 and R,z is inserted between an
16 input tern~inal 1 I and a ground, and a detection voltage VSNS is taken out in a
connection point of these resistors so that the detection voltage VSNSi s s~11)pliedto
the control circuit 12.
A reference voltage VREI; is supplietl to tlie control circnit 12, and tile
reference voltage VRFF and the detection voltage VsNs are co~npared in the control
20 circuit 12. \Vhcn VsNs > VRE~tli,e input voltage V, is deterniined to be abnomially
I~igli, and tln~s a control signal for torning on a s\\itclt is generated. Here, tlte
abnormal input voltage is appropriately set according to a voltage at tlte time of
actoal use and the specification of tlte Zener diodes. For example, the abnomtal
input voltage is assomed to be about twice the actually used voltage. Normally, in
25 the case of 800 V, the switch is turned on witli 1.6 kV. Also, although not illustrated,
\\,lien a11 oi~tputv oltage is abnorntal rather than tlte inp[~tv oltage, a switcli SWI or
SW2 may be set to be turned on. An output voltage considered to be abnom~al is,
for example, an output voltage \\,it11 a valc~ea bout t\vice an assonied outpot voltage.
The switch SWI is connected in parallel to tlte series circuit of tlte Zener
30 diodes Zl1 to Zi,,, and the switch SW2 is connected in parallel to the series circuit of
tlte zener diotles to Z2,. The switcl~es SW1 and SW2 are controlled by an
output of the co~itrocl ircuit 12. Wtieti an abnortnal input voltage is detected by tlie
control circuit 12, both of tlie switches SWI and SW2 are turned on. Accordingly,
both of tlie IGBT 1 and tlie IGBT 2 are considered to be h~rnedo ff.
Switches Slz, S I ~..,., and SI, are connected in parallel to the zener diodes
5 other than the zener diode Zll among the zener diodes Zll to ZI,. Likewise,
switches S22, S23, ..., and Szm are connected in parallel to the zener diodes other tlian
tlie zener diode 221 aniolig tlie zener diodes 2 2 1 to Z2,.
These switches are configured to be i~idividually co~ltrolled by control
signals generated by a control circuit (not illustrated). That is, a gate voltage Vol of
10 tlie IGBT 1 and a gate voltage Vo2 of the IGBT 2 are changed according to
connection states of tlie switches. As understood fro111 Equations (I) and (2), the
output voltage V,, is deter~nined by tlie voltage Val and tlie outpot voltage V, is
determined by the voltage VGZ. Accordi~iglyd, esired output voltages are formed by
co~~trollit~lieig s \vitclies S12 to SI, and tlie s\\ritclies S22 to S2",.
15 The control on tlie s\vitclies S It~o S I, and the s\vitcIies S22 to Sz,, may be
cl~anged in a temporal direction. For example, wlien feeding of po\ver to the load
ZL starts, tlie outl~l~vot ltages can be gradually increased (soft start) by gladually
increasing the voltage VGI a11d10r tlie voltage VG~. 111 contrast, tlie output voltages
may be gradt~allyd ecreased.
20 A capacitor CII is connected in parallel to tlie series circuit of the zener
diodes Zll to ZI,, and a capacitor C ~isI c onnected in parallel to the series circuit of
the zener tliodes Z21 to Z?,. The capacitors CII atid Czl have a fi~tiction of
prevet~ti~iagll excessive current fro111 flo\ving abroptly in the series circuits of the
zener diodes to protect the zener diodes.
25 111 the above-described second embodi~iient of the present disclosure, the
f~llo\\~inogp erational effects can be obtained ill addition to tlie opel.ationa1 effects
obtained i l l tlie first enibotliment:
It is possible to co~~tsothle output voltages in the temporal direction in
\\hicli tbc output voltages participating in tlie loatl are gradually increased; and
30 it is possible to prevent an abruptly large current from flowing in the series
circuits of the zener tliodes to protect tlie zener diodes.
<3. Application examples>
"Power storage device in a house according to an application exan~ple"
An example ill which an e~nbodi~neonft the present disclosure is applied to
a power storage device for a house will be described with reference to FIG. 4. For
5 example, in a power storage device 100 for a house 101, power is supplied to an
electric storage device 103 via a power nehvork 109, an information network 112, a
smart meter 107, a power hub 108, and the like from a centralized power supply
system 102 such as thermal power generation 102a, nuclear pomer generation 102b,
or hydropower generation 102c. Jn addition, power is supplied fro~n an
10 independent power supply such as an ill-house polver generation device 104 to the
electric storage device 103. The power supplied to the electric storage device 103 is
stored. Power used in the house 101 is fed using the electric storage device 103.
The same power storage device can be used not only in tl~el1 011se 101 but also in
other buildings.
15 The in-house power generation device 104, po\ver consumption devices 105,
tile electric storage device 103, a control tlevice 110 controlling each device, the
smart meter 107, and sensors 11 I acquiring various kinds of inforn~ationa re installed
in the house 10 1. Tl~ere spective devices are co~~nectevtila tl~ep ourer network 109
ant1 the infor~natio~nel t\vork 1 12. Po\ver generated using a solar cell, a fhel cell, or
20 the like as the in-l~ouse power generation device 104 is supplied to the power
consumption devices 105 and/or tl~e electric storage device 103. Tlle power
c o ~ l s ~ ~ n ~dpevt icoe~s ~1 05 include a refrigerator 105a, an air conditioner 105b, a
television receiver 105c, and a bat11 105d. Furillel; the power consumption devices
105 include electrically driven vehicles 106. The electrically driven vehicles 106
25 include an electric vehicle IOGa, a hybrid car 106b. and an electric motorcycle IO6c.
The electric storage device 103 includes secondary cells or capacitors. For
exa~nple,t1 1e electric storage device 103 itlclodes lithium ion seco~tdaryc ells. The
lithiinn ion secondary cells may be fixetl cells or cells used for tl~eel ectrically driven
vel~icles1 06. The smart meter 107 has a fi~nctioio~f measuring a use amount of
30 connnercial power and tmnsmitting the measured use alnount to a power coml)any.
The power network 109 may be one of direct-cc~rrent power feetl. alternating-current
power feed, and contactless power feed or rnay be a combination of a plurality
thereof.
Examples of the varioos sensors 11 1 include a tilotion detection sensor; an
illuminance sensol; an object detectiot~ sensot; a power consumption sensor, a
5 vibration sensol; a contact sensol; a temperature sensot; and an infrared sensor.
Itifo~lnation acqnirecl by the various sensors I I I is transmitted to the control device
110. Based on the information fro~ntl ~ese nsors 11 1, weather states, human states,
or the like are coniprehended so that energy consumption can be minimized by
automatically controlling the power consomption devices 105. Further, the control
10 device 110 can transmit informatioil regarding the honse 101 to an external power
conipany or the like via the Ititemet.
Processes sncl~ as partition of power lines, and direct-curretit and
alternating-current conversion are performed by the po\ver hub 108. Exa~npleso f
communication schetties of the information net\vork 112 connected to the control
15 device 1 I0 include a neth hod of using a commn~~icatioint erface sncli as a Universal
Asynchronoos Receiver-Trans~i~itte(rU ART) and a method of using a sensor
net\vork by a \\!ireless commonication standard such as Bloetootli (registered
trademark), ZigBee (~tgistered trade~nark), or Wi-Fi (registered trademark). In the
Bluetootli (registered traden~ark)s cl~eoie,m nltitnedia communication is applied and
20 one-to-~nnltic onnection cotnmuaicatio~ci all be performed. In ZigBee, the physical
layer of Institute of Electrical and Electro~~icEsl lgineels (IEEE) 802.15.4 is used.
IEEE 802.15.4 is tlie name of a short-distance wireless nehvork standard know11 as a
Personal Area Nehvork (PAN) or \\'i~.elcss( W) PAN.
The control device 110 is connected to an extenial server 113. The server
25 113 may be managed by any of tlie lioose 101, a po\Irer company, atid a service
provider. Examples of infor~nation tra~is~nittcadn d received by tlie server 113
include power co~~sumptioinn for~nation, life pattern infor~iiatiot~a, power fee,
\\reather iiifor~nation,~ ~atnldails aster inforniatio~~a.n d information regarding pou'er
trade. Such iufor~nation may be transmitted and received to and from a po\trer
30 coosua~ption device (for exa~uple, a television receiver) iin tl~e l~onse or may be
transmitted and received to and from a device (for example,-a ~iiobilep l~one)o utside
the house. Such infom~ation rnay be displayed on a device having a display
fnnction, snch as a televisio~i receiver, a mobile telephone, or a personal digital
assistant (PDA).
Tlie control device 110 controlling each unit includes a CPU, a RAM, and a
5 ROM and is received in the electric storage device 103 in this example. Tlie control
device 110 is connected to the electric storage device 103, the in-house power
generation device 104, the power co~isuniption device 105, the various sensors 11 1,
and the server 1 I3 via the information nehvork 112 and has, for example, a filnction
of adjusting a use amount and a generation amount of commercial power. Note that,
10 in addition, the control device 110 tilay have a fnnction of performing power trade in
a power market.
As described above, the power generated not only by the centralized potver
supply system 102 soch as the thermal power generation 102a, the ncslear power
generation 102b: or the liydropo\\~erg eneration 102c but also by the in-house power
15 generation device 104 (solar light generatio11 or wind power generation) can be
stored in the electric storage device 103. Accordingly, even \vl>en power generated
by tlie in-l~onsep o\ver gc~ierationt levice 104 varies, co~itrolc an be perfornied sucli
tliat an a~nonnt of power transmitted to the ontsitle is allowed to be constant or a
necessary mount of ponreris discharged. For example, a use method of storing
20 power obtained by solar light generation in the electric storage device 103, storing
nighttime power for which n fee is cheap at nighttime in the electric storage device
103, and discharging the power stored it1 the electric storage device 103 at a time at
which a fee is expensive during the day can be nsed.
Also, in this example, the esalnple in which the control device 110 is
25 received in the electric storage device 103 has been described, but tlie control device
110 may be received in the s11ia1-Cn ieter 107 or may be configured solely. Further,
tlie po\ver slolage device 100 may be t~setl for a plurality of l~onses in a mnltipledwvelling
complex or niay be nsed for a plnrality of detached lionses.
"Power storage device in a vel~iclea ccording to an applicatio~e~xa niple"
30 An example ill \vhicl~a n einbodi~nento f the present disclosore is applied to
a power storage device \\,ill be described with reference to FIG. 5. FIG. 5 is a
diagram schen~atically illustrating one example of the configuration of a hybrid
vehicle adopting a series hybrid systeln to which an embodiment of the present
disclosure is applied. The series hybrid systeln is a vehicle that moves by an engine
and runs by a power driving force conversion device, using power having generated
5 by a generator or power stored in a battery.
An engine 201, a generator 202, a po\ver driving force conversion device
203, a driving wheel 204a, a driving wileel 2046, a vehicle wheel 205a, a vehicle
wheel 205b, a battery 208, a \rehicle control device 209, various sensors 221, and a
charging inlet 21 1 are inounted on a hybrid vehicle 200.
10 The hybrid vehicle 200 runs using the power driving force conversion
device 203 as a po\ver source. An example of the power driving force conversion
device 203 is a motor. The power driving force conversion device 203 operates by
power of the battery 208 and a rotational force of tile potver driving force conversion
device 203 is delivered to the driving \\,heels 204a and 204b. Also, by ositlg direct-
15 corrent and alter~~ating-curret1(Dt C-AC) conversion or reverse (AC-DC) conversion
\\,here necessary, the power tlriving force conversion device 203 can be applied to
either an alternati~lg-curre~m~ott or or a direct-current motor. Tlie various sensors
210 control the number of rotations of the engine or control opening (throttle
opening) of a throttle valve (not illustrated) via the vehicle control device 209. The
20 various sensors 210 include a speed sensol; an acceleration sensor and an engine
rotation number sensor.
A rotational force of the engine 201 is delivered to the generator 202 and
power generated using the rotational force by the generator 202 can be stored in the
battery 208.
25 When the hybrid vel~icle is decelerated by a braking mechanisiu (not
illustrated), a resistant force at the time of the decele~ation is added as a rotational
force to tile power driving force conversio~d~e vice 203 and regenerative power
generated using the rotational force by the po\trer driving force conversion device
203 is stored in the batte~y2 08.
30 When the battery 208 is connected to an external po~vers upply of the hybrid
vehicle, power is supplied fi.0111 the external po\s7er stlpply osing the charging inlet
211 as an input port and can be stored.
Althougli not illustrated, an info~niation processing device performing
infoi~iiationp rocessing regarding vehicle co~itroal ccording to infor~~~atrieogna rding
a secondary cell liiay be provided. An example of the infor~natio~pir ocessing
5 device inclodes ail i~~foniiatpioro~c~e ssit~gd evice that displays a remaining battery
capacity based on i~~formatiroe~gai rding a re~iiainingc apacity of the batte~y.
The series hybrid vehicle that moves by the engine atid runs by the motor
using the power liaving generated by the generator or tlie power stored in the battery
11as been described above as an example. Ho\wreve~; at1 embodiment of the present
10 disclosure cat1 be etiectively applied even to a parallel l~ybridv el~icleth at uses any of
the outputs of an engine and a motor as a driving source and appropriately switcl~es
and uses three schemes of ro~iningo nly by the engine, ronning only by the inotol;
and ronning by tl~ee ngine and the tuotor. Furtheh an embodimeiit of tlie present
disclosure can be effectively applied even to a so-called electrically driven vellicle
15 that is driven and runs only by a driving motor witbout usiiig an engine.
Additionally, the present tecl~iiologyn iay also be configored as below.
(1)
A powver supply circuit including:
a first series regulator ii~cludiiiga first set~niconductore le~~lea~nldt a first
20 constant voltage source; and
a second series regulator iticloding a second setniconductor ele~nenta nd a
second coilstant voltage source,
wvliereit~ tl~e first series regt~lator and tlie second series regulator are
cascaded and an input voltage to the first series regulator is a high voltage equal to or
25 greater than 500 V.
(2)
The power supply circuit according to (I),
wlierein the first se~~iiconductoerl ement and the second semicondoctor
ele~iienet ac11 include an illput electrode, at1 output electrode, and a control electrode,
30 and
wvlierein tlle first constant voltage source and the seco~td constant voltage
soulre are connected to tlie corittrol electrode of the first se~iiicoriductose lement and
the control electrode of tlie second semiconductor element, respectively.
(3)
The power supply circuit according to (I),
5 wherein a detection unit configured to detect a value of at least one of the
input voltage and the oc~tpovt oltage is provided, and
wherein, when the detection 1111idt etects that the value is abtiortnally greater,
at least one of the first constarit voltage source and the second constant voltage
sonrce is controlled and at least one of tlie first-semicond~~ctoesle lnetit and tlie
10 second semiconductor elenient is torned off.
(4)
Tlie power supply circuit accorditig to (l), wherein switches configured to vary
voltage \,slues by the first constant voltage source and the second constant \coltage
source are provided.
15 (5)
Tlie power supply circuit accortling to (4), wherein the switch chaoges the voltage
\due inn teniporal tlirection.
(6)
Tlie power supply circuit according to (I), \\,lierein a capacitor-is provided in parallel
20 to each of tlie first co~lsta~viot ltage source and tlie second corlstatlt voltage source.
(7)
The po\ver supply circuit according to (6), wl~ereci~ur~re nt li~nitatio~elie ments are
connected to tlie col~tlale lectrode of the first semiconductor element and the control
electrode of tile second se~nico~iducteolre lllent.
25 (8)
A power supply system i~lcluding:
an electric storage unit;
a s\vitch ele~nent co~lfiguretl to co~itrol charging and discharging of the
electric storage unit;
30 a co~itrocl irc~~ciot~ lfiguredt o cot~trotlh e s\\,itcli element; and
a power supply circuit configured to form operatio~lal potver of tlie control
circ~~firot m a voltage of tlie electric storage unit,
wherein the power supply circuit has a configuration according to (I).
(9) ~ -
An electric storage device including:
6 the power supply system according to (8),
wherein direct-current power formed from an external power supply system
is used as charging power of tlie electric storage unit, and
wherein output power of the electric storage unit is supplied to an electronic
device. ., ..,
10 4. Modification exa~nples>
The e~nbodimentso f the present disclosore have been specifically described
above, bot tlie above-described e~nbodiments are not limiting. Various
~iiodificationsc an be ~iiadeb ased on the teclitiical spirit and essence of the present
disclosure. For example, tlic cont~gurationsn, ietliods, processes, shapes, materials,
15 nuliierical values, and tlie like eseniplified in tlie above-described embodinrents are
~iierely examples, and configorations, metliods, psocesses, shal,es, ~iiaterials,
no~nericnl values, and tlie like different tlierefioni may be usetl as necessary. For
example, tlie values of tlie voltages and tlie values of tlie currents described above arc
nierely examples and otlier values may be used. Fnrtliel; \\,hen tlie outpot voltages
20 are monitored a ~tdhe outpnt values are abnormally large values, tlie semicondactor
elcrnerits may be turned off. Furthel; eleniecits otlier than tlie IGBTs, such as Field
Effect Transistors (FETs), inay be used as tlie semicontluctor elements. Furtliet;
tliree or Inore series regulators may be cascaded. Also, the configuratiotis, methods,
processes, shapes, materials, nunierical values, acid tlie like exelnplified in tlie above-
25 described embodiments can be combined mutually as long as they do not depart t'soiii
tlie gist of tlie present disclosure.
It should be onderstood by those skilled in tbe art that various modifications,
combinations, sub-combinations and alterations may occur depe~tdi~iogn design
require~nents and otlier factors insofar as they are within the scope of the appended
30 claims or the equivalents tliereof.

What is claims :
1. A power supply circuit comprising:
a first series regulator including a first semiconductor elernelit and a first
constant voltage source; arid
5 a second series regulator includirig a second semicot~ductore lement and a
second constant voltage source,
wherein tile first series regulator and tlie second series regulator are
cascaded and an input voltage to the first series regulator is a high voltage equal to or
greater than 500 V.
10
2. The po\ver supply circuit accordit~gto claitii I,
wherein the first se~niconductor element atid the second semiconductor
elemelit each include an input electrode, an output electrode, acid a control electrode,
and
16 wherein the first constant voltage source and the seco~~codn stant voltage
soorce are co~i~~ecttoe dth e control electrode of the first semiconductor element and
the control electrode of the seco~ids e~i~ico~iducetloelrl lent, respectively.
3. Tlie power supply circuit according to claim 1, -,
20 \vl~erein a detectioii unit configt~red to detect a value of at least otie of tlie
input voltage and the output voltage is provided, and
\\,herein, when tlie detection unit detects that the value is greater than a
reference value, at least one of the first collstaot voltage sotrrce and the second
co~lstatitv oltage soorce is co~~trollead~ itla t least one of the first semico~id~~ctor
25 elelllent and the seco~ids emicondoctor elenlent is turned off.
4. ?'lie power supply circ~~aictc ording to claim I, wherein s\vitches configaretl to
vary voltage \,slues by tlie first constant voltage source and tlie second constant
voltage source are provided.
30
5. Tlie po\trer snpply circuit accordi~lgto claim 4, \\,lierein tlie switch changes tlie
~'oltagcv alue in a tempol.al direction.
6. The power supply circuit according to claim I, wlierein a capacitor is providcd in
parallel to each of the first consta~itv oltaxe source and the sccond constant voltage
5 source.
7. The power supply circuit according to claim 6, wl~erein current limitation elements
are connected to the control electrode of the first semiconductor element and the
control electi.ode of the second semiconductor element.
10
8. A power sc~pplys ystem comprising:
an electric storage unit;
a s\\,itcli elenlent configured to control chal-ging and discharging of the
electric stol-age unit;
15 a control circuit configc~~etod COII~I-01 the s\\;itcIi element; and
a power supply circuit configoretl to form operational power of the contl-ol
cil-cuit froin a voltage of the electric storage unit.
wherein thc power supl~lyc ii-cuit has a conligulation according to clai~n1 .
. ~ . -.
20 9. An electl-ic storage device comprisi~ig:
the po\versul~plys ystem according to claim 8,
wherein tlircct-current pouter formed from an external poxver supply syste111
is l~sctla s charging p o ~ ~o~f cthre electric storage onif, and
wherein output power of the electric storage unit is sc~ppliedto an electronic
25 device.