Power supply device

A power supply device includes: a first high-voltage line for exchanging the electric power externally; a second high-voltage line for applying current flowing in a direction opposite to the first high-voltage line; a plurality of batteries; a plurality of SUs, the SUs being provided corresponding to the respective batteries, switching a connection state of the batteries to the first high-voltage line, and being disposed in a circle; and an SCU that controls the SUs. The SU can switch between a first state in which the battery corresponding to the SU is connected in series to the first high-voltage line and a second state in which the battery is not connected to the first high-voltage line. The SCU controls the SUs to switch to the first state or the second state in accordance with a voltage of the electric power to be charged and discharged.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2020-176142 filed on Oct. 20, 2020, incorporated herein by reference in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a power supply device, and more particularly to a power supply device capable of charging and discharging electric power.

2. Description of Related Art

In the related art, there is known a sweep power supply device capable of outputting electric power of a desired output voltage by switching between a state in which a plurality of secondary batteries is connected in series to a power line and a state in which the secondary batteries are not connected (for example, refer to Japanese Unexamined Patent Application Publication No. 2018-74709 (JP 2018-74709 A).

SUMMARY

However, when the area of a closed loop surrounded by the power line is large, radiation in the normal mode becomes large. Therefore, there is a concern that the radiation may affect the surroundings such as malfunction of electronic devices, for example, a control device.

The present disclosure has been made to solve the above-mentioned issue, and an object of the present disclosure is to provide a power supply device capable of reducing an effect of radiation imposed on the surroundings.

A power supply device according to the present disclosure is a power supply device that is able to charge and discharge electric power, and includes: a first power line for exchanging the electric power externally; a second power line for applying current flowing in a direction opposite to the first power line while exchanging the electric power externally, a plurality of secondary batteries; a plurality of switching units, the switching units being provided corresponding to the respective secondary batteries, switching a connection state of the secondary batteries to the first power line, and being disposed in a circle; and a control device that controls the switching units. The switching units are each switchable between a first state in which the secondary battery corresponding to the switching unit is connected in series to the first power line and a second state in which the secondary battery is not connected to the first power line. The control device controls the switching units to switch to the first state or the second state in accordance with a voltage of the electric power to be charged and discharged. One of the first power line and the second power line is disposed side by side with the other between the switching units adjacent to each other.

With this configuration, one of the first power line and the second power line for applying the current in the direction opposite to the first power line is disposed side by side with the other between the switching units adjacent to each other. For this reason, the closed loop surrounded by the power lines can be reduced as compared with the case where the adjacent switching units are connected to each other by only one power line of the outward path and the return path and the other power line extends along another path in which the other power line is not disposed side by side with the one power line, whereby the radiation can be reduced. As a result, the effect of radiation on the surroundings can be reduced.

The switching units adjacent to each other may be connected by the first power line and the second power line. With this configuration, the area of the closed loop surrounded by the power lines can be further reduced as compared with the case where the adjacent switching units are connected by only one of the first power line and the second power line, whereby the radiation can be further be reduced. As a result, the effect of radiation on the surroundings can be further reduced.

The power supply device may further include: a positive electrode power line that connects the switching unit and a positive electrode terminal of the secondary battery corresponding to the switching unit; and a negative electrode power line that connects the switching unit and a negative electrode terminal of the secondary battery corresponding to the switching unit. The switching unit may further include a one-side first terminal for connecting the first power line connected to the switching unit on one adjacent side, an another-side first terminal for connecting the first power line connected to the switching unit on another adjacent side, a positive electrode connection terminal for connecting the positive electrode power line connected to the corresponding secondary battery, a negative electrode connection terminal for connecting the negative electrode power line connected to the corresponding secondary battery, a first electric path that connects the one-side first terminal and the positive electrode connection terminal, a second electric path that connects the other-side first terminal and the negative electrode connection terminal, a bypass electric path that connects the one-side first terminal and the other-side first terminal without passing through the secondary battery, a first switching unit that is provided in the middle of the bypass electric path and opens and closes the bypass electric path, and a second switching unit that is provided in the middle of the first electric path or the second electric path and opens and closes the first electric path or the second electric path. The first state may be a state in which the first switching unit is closed and the second switching unit is opened, and the second state may be a state in which the first switching unit is opened and the second switching unit is closed.

With this configuration, the secondary battery can be connected in series or not connected to the first power line by simply opening and closing the first switching unit and the second switching unit.

The switching unit may further includes: a one-side second terminal for connecting the second power line connected to the switching unit on the one adjacent side; an another-side second terminal for connecting the second power line connected to the switching unit on another adjacent side; and a return electric path that connects the one-side second terminal and the other-side second terminal.

With this configuration, the switching unit including the first and second electric paths through which the current of the first power line flows includes the return electric path through which the current of the second power line flows. Therefore, the area of the closed loop can be further reduced, and the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

The power supply device may further include: a positive electrode reverse power line for applying current flowing in a direction opposite to the positive electrode power line; and a negative electrode reverse power line for applying current flowing in a direction opposite to the negative electrode power line. The positive electrode power line and the positive electrode reverse power line may be disposed side by side with each other. The negative electrode power line and the negative electrode reverse power line may be disposed side by side with each other.

With this configuration, the positive electrode reverse power line and the negative electrode reverse power line for applying the current flowing in the opposite direction are connected so as to be disposed side by side with the positive electrode power line and the negative electrode power line connecting the switching unit and the secondary battery, respectively. Therefore, the area of the closed loop can be further reduced, and the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

The positive electrode power line and the positive electrode reverse power line may be configured by a shielded wire including the positive electrode power line and the positive electrode reverse power line as core wires. With this configuration, the shield of the shielded wire serves as the return line of the positive electrode power line and the positive electrode reverse power line, whereby the common components of the positive electrode power line and the positive electrode reverse power line can be returned to the ground. Therefore, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

The first power line and the second power line may be twisted together between the switching units adjacent to each other. With this configuration, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

The switching units adjacent to each other may be connected by a return path line in addition to the first power line and the second power line. With this configuration, the common components of the first power line and the second power line can be returned to the ground by the return path line. Therefore, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

The switching units adjacent to each other may be connected by a shielded wire including the first power line and the second power line as core wires. With this configuration, the shield of the shielded wire serves as the return line of the first power line and the second power line, whereby the common components of the first power line and the second power line can be returned to the ground. Therefore, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

According to the present disclosure, a power supply device capable of reducing the effect of radiation on the surroundings can be provided.

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following description, the same components are designated by the same reference signs. The same applies to names and functions thereof. Therefore, the detailed description of the above will not be repeated.

FIG.1is a diagram showing the outline of the configuration of a power supply device90of the related art. With reference toFIG.1, the power supply device90is a device that supplies electric power to an external device that consumes the electric power such as a load40, or stores the electric power from an external electric power source such as a commercial power source or a generator. The power supply device90includes sweep units (hereinafter referred to as “SU”)910A to910N, battery units920A to920N, a capacitor930, a voltage sensor940, a current sensor950, and a string control unit (hereinafter referred to as “SCU”)900. A string is a string in which batteries such as secondary batteries are connected in series, and is also called a battery string.

The power supply device90is connected to the load40via a positive electrode terminal981P and a negative electrode terminal981N. A system main relay (SMR)30is connected between the positive electrode terminal981P and the load40. The positive electrode terminal981P and the SMR30are connected by a power line38. The SMR30and the load40are connected by a power line48P. The negative electrode terminal981N and the load40are connected by a power line48N.

The SUs910A to910N respectively switch whether the battery units920A to920N are connected in series to a power line including high-voltage lines980A to980Y. The SUs910A to910N are connected to the battery units920A to920N, respectively by high-voltage lines through which high voltage current can flow. In the present embodiment, the number of combinations of the SU and the battery unit is 14. However, the number of combinations is not limited to this and only needs to be a plural number. Further, “A” to “N” at the end of the reference sips respectively indicate that the configurations are related to the SUs910A to910N or the battery units920A to920N.

The SU910B is connected to the adjacent SU910A by the high-voltage line980B through which high voltage current can flow. Similarly, the SUs910C to910N are connected to the adjacent SUs910B to910M by the high-voltage lines980C to980N, respectively. The SU910A is connected to the positive electrode terminal981P of the power supply device90by the high-voltage line980A on the opposite side of the high-voltage line980B connected to the SU910B. The current sensor950that measures the current flowing through the high-voltage line980A is connected in series in the middle of the high-voltage line980A. The SU910N is connected to the negative electrode terminal981N of the power supply device9W by the high-voltage line980Y on the opposite side of the high-voltage line980N connected to the SU910M. The high-voltage lines980A and980Y are connected by the high-voltage line980Z. The capacitor930that smoothens the voltage between the high-voltage lines980A and980Y and the voltage sensor940that measures the voltage between the high-voltage lines980A and980Y are connected in series in the middle of the high-voltage line980Z.

The SCU900controls the SUs910A to910N. Specifically, the SCU900receives information on the temperature, voltage, and the like of the battery units920A to920N from the SUs910A to910N via control lines990A to990Y for transmitting control signals, and also receives information indicating the voltage and current from each of the voltage sensor940and the current sensor950. The SCU900transmits signals for controlling the SUs910A to910N using the information above. Further, the SCU900transmits a signal for controlling the SMR30via the control line990Z, a control terminal991, and the control line39. Here, the control lines990A to990Z and the control line39are local area network (LAN) cables. However, the control lines990A to990Z and the control line39may be other well-known types of communication media such as wireless LAN. Further, the communication protocol may be any well-known protocol.

The SU910B is connected to the adjacent SU910A by the control line990B. Similarly, the SUs910C to910N are connected to the adjacent SUs910B to910M by the control lines990C to990N, respectively. The SU910A is connected to the SCU90) by the control line990A. The SU910N is connected to the SCU900by the control line990Y on the opposite side of the control line990N connected to the SU910M.

FIG.2is a diagram showing the outline of the configurations of the SUs910A to910N of the power supply device90of the related art. The SUs910A to910N have the same configuration. Therefore, with reference toFIG.2, the SU910A will be described as a representative. Further, the battery units920A to920N have the same configuration. Therefore, the battery unit920A will be described as a representative.

The battery unit920A includes a battery921A. The battery921A is a secondary battery, for example, a lithium ion battery. The battery unit920A includes a positive electrode terminal922PA to which the positive electrode of the battery921A is connected and a negative electrode terminal922NA to which the negative electrode of the battery921A is connected.

The SU910A includes a control unit911A, a first switching element912A, a second switching element913A, and a capacitor914A.

In the present embodiment, the first switching element912A and the second switching element913A are metal oxide semiconductor field effect transistors (MOS-FET), and controlled by the control unit911A to open and close the electric path. Note that, the first switching element912A and the second switching element913A may be other devices (for example, other types of transistors, thyristors, relays) as long as the first and the second switching elements912A and913A are controlled by the control unit911A and can open and close the electric path.

The SU910A includes a positive terminal918PA and a negative terminal918NA. The positive terminal918PA and the negative terminal918NA are terminals for connecting the high-voltage line that is connected to another SU such as the SU9108, or connected to the positive electrode terminal981P and the negative electrode terminal981N of the power supply device90.

The SU910A includes a battery positive electrode connection terminal917PA and a battery negative electrode connection terminal917NA. The battery positive electrode connection terminal917PA and the battery negative electrode connection terminal917NA are terminals for connecting the high-voltage lines982A and983A connected to the positive electrode terminal922PA and the negative electrode terminal922NA of the battery unit920A, respectively.

An electric path915A connects from the positive terminal918PA to the battery positive electrode connection terminal917PA. An electric path916A connects from the middle of the electric path915A to the negative terminal918NA and the battery negative electrode connection terminal917NA. The electric path915A and the electric path916A are connected to each other by the capacitor914A.

The first switching element912A is connected between a connection point of the electric path916A with the electric path915A and a connection point of the electric path916A with the capacitor914A. Further, the first switching element912A is connected to the control unit911A by a control line.

The second switching element913A is connected between a connection point of the electric path915A with the electric path916A and a connection point of the electric path915A with the capacitor914A. Further, the second switching element913A is connected to the control unit911A by a control line.

The control unit911A is connected to control line connection terminals919UA and919LA. The control line connection terminals919UA and919LA are terminals for connecting the control line to be connected to another SU such as the SU910B or the SCU900.

The battery positive electrode connection terminal917PA of the SU910A and the positive electrode terminal922PA of the battery unit920A are connected by the high-voltage line982A. The battery negative electrode connection terminal917NA of the SU910A and the negative electrode terminal922NA of the battery unit920A are connected by the high-voltage line983A.

When the first switching element912A and the second switching element913A are turned on at the same time, this causes a short-circuit state. Therefore, when one of the first switching element912A and the second switching element913A is turned on, the other is turned of.

When the first switching element912A is on and the second switching element913A is off, the positive terminal918PA and the negative terminal918NA are connected without passing through the battery921A. That is, when the battery921A is not connected to the high-voltage lines980A and980B, the electric power of the battery921A cannot be exchanged externally of the SU910A.

When the first switching element912A is off and the second switching element913A is on, the positive terminal918PA and the negative terminal918NA are connected through the battery921A. That is, when the battery921A is connected in series to the high-voltage lines980A and980B, the electric power of the battery921A can be exchanged externally of the SU910A,

FIG.3is a diagram for explaining the control of the SUs910A to910N in the power supply device90of the related art. As the control of the SUs910A to910N, for example, the same method as the control shown in JP 2018-74709 A can be used. The following control method will be described.

With reference toFIG.3, the SCU900includes a gate circuit901and delay circuits9111A to9111N (inFIG.3, the delay circuits9111A to9111C are shown). The gate circuit901generates a gate signal that is a rectangular wave signal for controlling the first switching elements912A to912N and the second switching elements913A to913N, and outputs the gate signals to the first SU910A and to the delay circuit among the delay circuits9111A to9111N, that is, the delay circuit9111A, corresponding to the first SU910A.

The delay circuits9111A to9111M delay the input gate signal for a predetermined delay time and output the gate signal to the SUs910B to910N of the next stage, and output the gate signal to the delay circuit of the next stage of the delay circuits9111B to9111N. The predetermined delay time is changed in accordance with the input and output voltage of the power supply device90and the number of stages of the SUs. Note that, the delay circuits9111A to9111N may be provided in the SUs910A to910N, respectively.

When the gate signal is input from the gate circuit901or the delay circuits9111A to9111M, the control units911A to911N of the SUs910A to910N output the gate signal to the second switching elements913A to913N while delaying rising of the input gate signal by a predetermined dead time dt, and output the gate signal to the first switching elements912A to912N after the input gate signal is inverted while slightly delaying rising of the inverted gate signal (by predetermined dead time dt).

When the gate signal is input from the gate circuit901or the delay circuits9111A to9111M, the control units911A to911N of the SUs910A to910N may output the gate signal to the first switching elements912A to912N while delaying rising of the input gate signal by the predetermined dead time dt, and output the gate signal to the second switching elements913A to913N after the input gate signal is inverted while slightly delaying rising of the inverted gate signal (by predetermined dead time dt).

The first switching elements912A to912N and the second switching elements913A to913N are turned on from off when the gate signal rises, while the first switching elements912A to912N and the second switching elements913A to913N are turned off from on when the gate signal falls.

With this configuration, when the input gate signal rises, the first switching elements912A to912N are turned off from on, and after a short time (dead time dt) from rising of the input gate signal, the second switching element913A to913N are turned on from off. Further, when the input gate signal falls, the second switching elements913A to913N are turned off from on, and after a short time (dead time dt) from falling of the input gate signal, the first switching elements912A to912N are turned on from off.

A specific example is shown below. The respective voltages of the batteries921A to921N of the battery units920A to920N are set to 50 V. The number of combinations of the SUs910A to910N and the battery units920A to920N included in the power supply device90is 14. Therefore, the maximum voltage that the power supply device90can output is 50 V×14 sets×700 V.

A period F of the gate signal is set by summing the delay times of the SUs910A to910N. Therefore, when the delay time is lengthened, the frequency of the gate signal becomes low. When the delay time is shortened, the frequency of the gate signal becomes high. The delay time of the gate signal can be appropriately set in accordance with the specifications required for the power supply device90.

The following equation is established: a ratio G1of an on-time to the period F of the gate signal=the output voltage required for the power supply device90/the maximum voltage that the power supply device90can output. Strictly speaking, because the on-time ratio deviates by the amount of the dead time dt, the on-time ratio is corrected by feedback control or feedforward control.

For example, an example of a case where the output voltage required for the power supply device90is 220 V will be described. When it is assumed that the period F of the gate signal is 20 μs (equivalent to 50 kHz), the delay time is 20 μs/14≈1.43 μs (equivalent to 70 kHz). The ratio G1of the on-time of the gate signal is 220 V/700 V≈0.314.

When the power supply device90is operated based on the numerical values above, the output voltage has a rectangular wavy output characteristic that fluctuates between 50 V×4=200 V and 50 V×(4+1)=250 V. The fluctuation cycle of the output voltage is equal to the delay time and is 1.43 μs (equivalent to 70 kHz). In the power supply device90, many battery units920A to920N are connected in series. Therefore, the parasitic inductance of the entire circuit becomes a large value. Therefore, fluctuations in the output voltage are filtered, and the power supply device90outputs a substantially constant voltage of 220 V.

However, high frequency current of 50 kHz due to the period F of the gate signal and high frequency current of 700 kHz due to the fluctuation cycle of the output voltage caused by the delay time are superimposed on the high-voltage lines980A to980N, in addition to the current from the batteries921A to921N. Further, harmonics due to the high frequency currents above are also superimposed. The high frequency currents and harmonics sneak around the control lines990A to990N.

FIG.4is a diagram showing the outline of the power supply device90of the related art. With reference toFIG.4.FIG.4shows the configuration in which the connection states of the high-voltage lines980A to980N.980Y and the SUs910A to910N of the power supply device of the related art shown inFIG.1are simplified. As shown inFIG.4, the area of the closed loop configured by the high-voltage lines980A to980N,980Y and the SUs910A to910N (the dotted hatched portion inFIG.4) becomes wide. When the above-mentioned high-frequency current flows in the closed loop, radiation in a normal mode occurs. This is because the closed loop serves as a loop antenna. As the closed loop becomes larger, the radiation in normal mode also becomes larger. An electric field strength Ed (V/m) of the radiation due to the normal mode current is given by the following equation ( ).

Here, f is the frequency, I×s is the area of the loop, |I| is the current, and d is the distance to the point where the electric field strength Ed is obtained. It can be understood that the electric field strength is proportional to the closed loop area I×s based on the equation (1). Further, an electric field strength Ec (V/m) of the radiation due to the common mode current is given by the following equation (2).

In the case of the common mode, the closed loop is not considered as a loop antenna, and is considered as a monopole antenna. The effect of the electric field strength is significantly larger with the radiation due to the common mode current than the radiation due to the normal mode current. However, as the closed loop becomes smaller, the common mode current normally becomes smaller because the outward current and the return current cancel out.

As described above, when the area of the closed loop surrounded by the power line is large, radiations in the normal mode and the common mode become large. Therefore, there is a concern that the radiations may affect the surroundings such as malfunction of electronic devices, for example, a control device.

Therefore, the power supply device10includes a high-voltage line on the positive electrode side for exchanging the electric power externally, a high-voltage line on a negative electrode side for applying current flowing in a direction opposite to the high-voltage line on the positive electrode side while exchanging the electric power externally, a plurality of batteries, a plurality of SUs, and an SCU that controls the SUs. The SUs are provided corresponding to the respective batteries, switch the connection state of the batteries to the high-voltage line on the positive electrode side, and are disposed in a circle. The SU can switch between a first state in which the battery corresponding to the SU is connected in series to the high-voltage line on the positive electrode side and a second state in which the battery is not connected to the high-voltage line on the positive electrode side. The SCU controls the SUs to switch to the first state or the second state in accordance with the voltage of the electric power to be charged and discharged. One of the high-voltage line on the positive electrode side and the high-voltage line on the negative electrode side is disposed side by side with the other between the adjacent SUs.

With this configuration, one of the high-voltage line on the positive electrode side and the high-voltage line on the negative electrode side for applying the current flowing in the opposite direction is set to be disposed side by side to the other between the adjacent SUs. For this reason, the closed loop surrounded by the high-voltage lines can be reduced as compared with the case where the adjacent SUs are connected to each other by only one power line of the outward path and the return path and the other power line extends along another path in which the other power line is not disposed side by side with the one power line, whereby the radiation can be reduced. As a result, the effect of radiation on the surroundings can be reduced.

First Embodiment

FIG.5is a schematic diagram showing the outline of the configuration of a power supply device20A according to a first embodiment. With reference toFIG.5, the power supply device20A includes SUs210A to210N. InFIG.5, the batteries of the battery units are also included in the SUs210A to210N. The configurations of the SUs210A to210N are the same as the configurations of the SUs910A to910N of the power supply device90of the related art. The control of the SUs210A to210N is the same as the control of the SUs910A to910N of the power supply device90of the related art.

The SUs210A and2108are connected by a high-voltage line280PB on the positive electrode side. Similarly, the SUs210B to210M and the SUs210C to210N adjacent thereto are connected by high-voltage lines280PC to280PN on the positive electrode side, respectively. The positive electrode terminal (not shown) of the power supply device20A and the SU210A are connected by a high-voltage line280PA on the positive electrode side. The negative electrode terminal (not shown) of the power supply device20A and the SU210N are connected by a high-voltage line280N on the positive electrode side.

Each of the high-voltage lines280PB to280PN on the positive electrode side that is one of the high-voltage lines280PB to280PN on the positive electrode side and the high-voltage line280N on the negative electrode side is set to be disposed side by side with the high-voltage line280N on the negative electrode side that is the other between the SUs210A to210M and the corresponding SUs210B to210N adjacent thereto. In the state in which the high-voltage lines are disposed side by side, for example, the high-voltage lines280PB to280PN on the positive electrode side and the high-voltage lines280N on the negative electrode side come close to each other with the distance therebetween being a predetermined distance or less. The predetermined distance is several centimeters (less than 10 centimeters), preferably several millimeters (less than 10 millimeters). Note that, in the present embodiment, the distance between the two high-voltage lines means the distance between the central axes of the two electric wires. However, the present disclosure is limited to this. The distance between the two high-voltage lines may be the shortest distance between the two electric wires (distance between the outer surfaces of the two electric wires that are the closest to each other).

Note that, inFIG.5, a portion of the high-voltage line280PB disposed side by side with the high-voltage line280N (a portion parallel to the high-voltage line280N inFIG.5) and portions of the high-voltage line280PB connected to the SUs210A and210B (portions perpendicular to the high-voltage line280N inFIG.5) are shown to be almost the same length. However, in reality, the distance between the SU210A and the adjacent SU210B is considerably larger than the length of the portions of the high-voltage line280PB that are connected to the SUs210A and210B (for example, 10 times or more). That is, most of the high-voltage line280PB on the positive electrode side is disposed side by side with the high-voltage line280N on the negative electrode side (for example, in a state in which the most of the high-voltage line280PB comes close to the high-voltage line280N by a predetermined distance or less). The same applies to the other high-voltage lines280PC to280PN on the positive electrode side.

Further, the high-voltage line280PA on the positive electrode side connected to the positive electrode terminal is also set to be disposed side by side with the high-voltage line280N on the negative electrode side connected to the negative electrode terminal.

With this configuration, the power supply device20A according to the first embodiment has the area of the closed loop (the dotted hatched portion inFIG.5) that is significantly smaller than the area of the closed loop of the power supply device90of the related art shown inFIG.4(the dotted hatched portion inFIG.4). For example, the area of the closed loop can be reduced to one-tenth or smaller. When the area of the closed loop can be reduced to x % (0<x<100) as compared with the case of the related art, the electric field strength Ed (V/m) of the radiation due to the normal mode current can be reduced to x %.

Second Embodiment

In the first embodiment, the case where the SUs210A to210N are disposed side by side in one stage is schematically shown. In the second embodiment, the SUs210A to210N are disposed side by side in two stages.

FIG.6is a schematic diagram showing the outline of the configuration of the power supply device90of the related art. With reference toFIG.6,FIG.6is a diagram schematically showing the configuration of the power supply device90shown inFIG.1. InFIG.6, the batteries of the battery units are also included in the SUs910A to910N. InFIG.6, the closed loop of the power supply device90is a dotted hatched portion.

FIG.7is a schematic diagram showing the outline of the configuration of a power supply device20B according to a second embodiment. With reference toFIG.7, as compared with the power supply device90of the related art shown inFIG.6, in the power supply device20B shown inFIG.7, each of the high-voltage lines280PB to280PN on the positive electrode side or the high-voltage line280N on the positive electrode side (here, each of the high-voltage lines280PB to280PN on the positive electrode side) is set to be disposed side by side with the other (here, the high-voltage line280N on the negative electrode side) between the SUs210A to210M and the corresponding SUs210E to210N adjacent thereto, similar toFIG.5.

Note that, inFIG.7, a portion of the high-voltage line280PB disposed side by side with the high-voltage line280N (a portion parallel to the high-voltage line280N inFIG.7) and portions of the high-voltage line280PB connected to the SUs210A and210B (portions perpendicular to the high-voltage line280N inFIG.7) are shown to be almost the same length. However, in reality, the distance between the SU210A and the adjacent SU210B is considerably larger than the length of the portions of the high-voltage line280PB that are connected to the SUs210A and210B (for example, 10 times or more). That is, most of the high-voltage line280PB on the positive electrode side is disposed side by side with the high-voltage line280N on the negative electrode side (for example, in a state in which the most of the high-voltage line280PB comes close to the high-voltage line280N by a predetermined distance or less). The same applies to the other high-voltage lines280PC to280PN on the positive electrode side.

Further, the high-voltage line280PA on the positive electrode side connected to the positive electrode terminal is also set to be disposed side by side with the high-voltage line280N on the negative electrode side connected to the negative electrode terminal.

With this configuration, the power supply device20B according to the second embodiment has the area of the closed loop (the dotted hatched portion inFIG.7) that is significantly smaller than the area of the closed loop of the power supply device90of the related art shown inFIG.6(the dotted hatched portion inFIG.6). For example, the area of the closed loop can be reduced to one-tenth or smaller. When the area of the closed loop can be reduced to x % (0<x<100) as compared with the case of the related art, the electric field strength Ed (V/m) of the radiation due to the normal mode current can be reduced to X %.

Third Embodiment

In a third embodiment, as in the second embodiment, the SUs210A to210N are separately disposed into two stages. In the third embodiment, a case where the order of connection of the SUs210A to210N is different from that of the second embodiment will be described.

FIG.8is a schematic diagram showing the outline of the configuration of a power supply device20C according to the third embodiment. In the second embodiment, as shown inFIG.7, the SU210F located at the left end in the upper stage and the SU210G located at the right end in the lower stage are adjacent to each other. With reference toFIG.8, in the third embodiment, it is considered that the SU210F located at the left end in the upper stage and the SU210G located at the right end in the lower stage are not adjacent to each other, and the upper and lower stages are independent from each other.

In the upper stage, between the SUs210A to210E and the SUs210B to210F adjacent thereto, each of the high-voltage lines280PB to280PF on the positive electrode side or the high-voltage line280PG on the positive electrode side through which current in the direction opposite to the above voltage lines (here, each of the high-voltage lines280PB to280PF on the positive electrode side) is set to be disposed side by side with the other (here, the high-voltage line280PG on the negative electrode side), similar toFIG.5.

In the lower stage, between the SUs210G to210M and the SUs210H to210N adjacent thereto, each of the high-voltage lines280PH to280PN on the positive electrode side or the high-voltage line280N on the negative electrode side through which current in the direction opposite to the above voltage lines (here, each of the high-voltage lines280PH to280PN on the positive electrode side) is set to be disposed side by side with the other (here, the high-voltage line280N on the negative electrode side), similar toFIG.5.

Note that, inFIG.8, a portion of the high-voltage line280PB disposed side by side with the high-voltage line280PG (a portion parallel to the high-voltage line280PG inFIG.8) and portions of the high-voltage line280PB connected to the SUs210A and210B (portions perpendicular to the high-voltage line280PG inFIG.8) are shown to be almost the same length. However, in reality, the distance between the SU210A and the adjacent SU210B is considerably larger than the length of the portions of the high-voltage line280PB that are connected to the SUs210A and210B (for example, 10 times or more). That is, most of the high-voltage line280PB on the positive electrode side is disposed side by side with the high-voltage line280PG on the positive electrode side through which the current in the direction opposite to the high-voltage line280PB flows (for example, in a state in which the most of the high-voltage line280PB comes close to the high-voltage line280PG by a predetermined distance or less). The same applies to the other high-voltage lines280PG to280PN on the positive electrode side.

The high-voltage line280PA on the positive electrode side connected to the positive electrode terminal is also set to be disposed side by side with the high-voltage line280PG on the positive electrode side through which the current in the direction opposite to the high-voltage line280PA flows. The high-voltage line280N on the negative electrode side connected to the negative electrode terminal is also set to be disposed side by side with the high-voltage line280PG on the positive electrode side through which the current in the direction opposite to the high-voltage line280N flows.

With this configuration, the power supply device20C according to the third embodiment has the area of the closed loop (the dotted hatched portion inFIG.8) that is significantly smaller than the area of the closed loop of the power supply device90of the related art shown inFIG.6(the dotted hatched portion inFIG.6). For example, the area of the closed loop can be reduced to one-tenth or smaller. When the area of the closed loop can be reduced to x % (0<x<100) as compared with the case of the related art, the electric field strength Ed (V/m) of the radiation due to the normal mode current can be reduced to x %.

Fourth Embodiment

In the first to third embodiments, the high-voltage lines in the power supply devices20A to20C are routed as single electric wires. In the fourth embodiment, the high-voltage lines in the power supply device10are routed using parallel two lines.

FIG.9is a schematic diagram showing the outline of the configuration of a power supply device10according to the fourth embodiment. With reference toFIG.9, the power supply device10includes SUs110A to110N. InFIG.9, the batteries of the battery units are also included in the SUs110A to110N. The SUs110A to110N include, in addition to the configuration of the SUs210A to210N shown inFIG.5, two terminals for connecting high-voltage lines and an electric path that directly connects the two terminals.

The SU110A and the SU110B are connected by a high-voltage line180PB on the positive electrode side and a high-voltage line180NB on the negative electrode side. Similarly, the SUs110B to110M and the SUs110C to110N adjacent thereto are connected by high-voltage lines180PC to180PN on the positive electrode side and high-voltage lines180NC to180NN on the negative electrode side, respectively. The positive electrode terminal (not shown) of the power supply device10and the SU110A are connected by a high-voltage line180PA on the positive electrode side. The negative electrode terminal (not shown) of the power supply device10and the SU110A are connected by a high-voltage line180NA on the negative electrode side. Two terminals of the SU110N that are not connected to the SU110M are connected by a high-voltage line180Z as a termination process.

The combinations of the high-voltage lines180PA to180PN and the high-voltage lines180NA to180NN are each configured using parallel two electric wires. A stranded electric wire obtained by twisting the two electric wires may be used instead of the parallel two electric wires.

Because parallel two electric wires or a stranded electric wire is used, the high-voltage lines180PB to180PN on the positive electrode side and the high-voltage lines180NB to180NN on the negative electrode side are disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less) between the SUs110A to110M and the SUs110B to110N adjacent thereto. Because parallel two electric wires or a stranded electric wire is used, the predetermined distance is several millimeters (less than 10 millimeters). Further, the high-voltage line180PA on the positive electrode side and the high-voltage line180NA on the negative electrode side that are connected to the positive electrode terminal and the negative electrode terminal, respectively, are also set to be disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less).

With this configuration, the power supply device10according to the fourth embodiment has the area of the closed loop that is significantly smaller than the area of the closed loop of the power supply device90of the related art shown inFIG.4(the dotted hatched portion inFIG.4). For example, the area of the closed loop can be reduced to one-tenth or smaller. When the area of the closed loop can be reduced to x % (0<x<100) as compared with the case of the related art, the electric field strength Ed (V/m) of the radiation due to the normal mode current can be reduced to x %, Specific Example of Fourth Embodiment

FIG.10is a diagram showing a specific example of the outline of the configuration of the power supply device10according to the fourth embodiment. With reference toFIG.10, in the power supply device9) of the related art shown inFIG.1, the SUs910A to910M and the SUs9108to910N adjacent thereto are connected by high-voltage lines980B to980N, each of which is a single electric wire. Meanwhile, in the power supply device10according to the fourth embodiment, the SUs110A to110M and the SUs110B to110N adjacent thereto are connected by the high-voltage lines180B to180N, each of which is composed of two electric wires. A positive electrode terminal181P and a negative electrode terminal181N of the power supply device10and the SU110A are connected by the high-voltage line180A composed of two electric wires. The two electric wires consisting the high-voltage line180A on the positive electrode terminal181P side and the negative electrode terminal181N side are separated into the high-voltage lines180PA and180NA. A capacitor130and a voltage sensor140are connected between the high-voltage lines180PA and180NA. A current sensor150is connected in series to one of the two electric wires of the high-voltage line180NA.

FIG.11is a diagram showing the outline of the configurations of the SUs110A to110N of the power supply device10according to the fourth embodiment. The SUs110A to110N have the same configuration. Therefore, with reference toFIG.11, the SU110A will be described as a representative. Further, battery units120A to120N have the same configuration. Therefore, the battery unit120A will be described as a representative.

The battery unit120A includes a battery121A. The battery121A is a secondary battery, for example, a lithium ion battery. The battery unit120A includes a return positive electrode terminal122PRA and a return negative electrode terminal122NRA in addition to a positive electrode terminal122PA to which the positive electrode of the battery121A is connected and a negative electrode terminal122NA to which the negative electrode of the battery121A is connected. The return positive electrode terminal122PRA and the return negative electrode terminal122NRA are directly connected by an electric path123inside the battery unit120A.

The SU110A includes a control unit111A, a first switching element112A, a second switching element113A, and a capacitor114A.

In the present embodiment, the first switching element112A and the second switching element113A are MOS-FETs and are controlled by the control unit111A to open and close the electric path. Note that, the first switching element112A and the second switching element113A may be other devices (for example, other types of transistors, thyristors, relays) as long as the first and the second switching elements112A and113A are controlled by the control unit111A and can open and close the electric path.

The SU110A includes a return positive terminal118PRA and a return negative terminal118NRA in addition to the positive terminal118PA and the negative terminal118NA. The positive terminal118PA and the negative terminal118NA are terminals for connecting the high-voltage line on the positive electrode side that is connected to another SU, such as the SU110B, or connected to the positive electrode terminal181P of the power supply device10. The return positive terminal118PRA and the return negative terminal118NRA are terminals for connecting the high-voltage line on the negative electrode side that is connected to another SU, such as the SU110B, or connected to the negative electrode terminal181N of the power supply device10.

The SU110A includes a return battery positive electrode connection terminal117PRA and a return battery negative electrode connection terminal117NRA in addition to the battery positive electrode connection terminal117PA and the battery negative electrode connection terminal117NA. The battery positive electrode connection terminal117PA and the battery negative electrode connection terminal117NA are terminals for connecting high-voltage lines182A and183A connected to the positive electrode terminal122PA and the negative electrode terminal122NA of the battery unit120A, respectively. The return battery positive electrode connection terminal117PRA and the return battery negative electrode connection terminal117NRA are terminals for connecting high-voltage lines182RA and183RA connected to the return positive electrode terminal122PRA and the return negative electrode terminal122NRA of the battery unit120A, respectively.

An electric path115A connects from the positive terminal118PA to the battery positive electrode connection terminal117PA. An electric path116A connects from the middle of the electric path115A to the negative terminal118NA and the battery negative electrode connection terminal117NA. The electric path115A and the electric path116A are connected to each other by the capacitor114A.

An electric path115RA connects from the return positive terminal118PRA to the return battery positive electrode connection terminal117PRA. An electric path116RA connects from the middle of the electric path115RA to the return negative terminal118NRA and the return battery negative electrode connection terminal117NRA.

The first switching element112A is connected between a connection point of the electric path116A with the electric path115A and a connection point of the electric path116A with the capacitor114A. Further, the first switching element112A is connected to the control unit111A by a control line.

The second switching element113A is connected between a connection point of the electric path115A with the electric path116A and a connection point of the electric path115A with the capacitor114A. Further, the second switching element113A is connected to the control unit111A by a control line.

The control unit111A is connected to control line connection terminals119UA and119LA. The control line connection terminals119UA and119LA are terminals for connecting the control line to be connected to another SU, such as the SU110B, or the SU100.

The battery positive electrode connection terminal117PA of the SU110A and the positive electrode terminal122PA of the battery unit120A are connected by the high-voltage line182A. The return battery positive electrode connection terminal117PRA of the SU110A and the return positive electrode terminal122PRA of the battery unit120A are connected by the high-voltage line182RA.

The battery negative electrode connection terminal117NA of the SU110A and the negative electrode terminal122NA of the battery unit120A are connected by the high-voltage line183A. The return battery negative electrode connection terminal117NRA of the SU110A and the return negative electrode terminal122NRA of the battery unit120A are connected by the high-voltage line183RA.

The combination of the high-voltage lines182A and182RA is configured using parallel two electric wires. The combination of the high-voltage lines183A and183RA is configured using parallel two electric wires. A stranded electric wire obtained by twisting the two electric wires may be used instead of the parallel two electric wires.

Because parallel two electric wires or a stranded electric wire is used, the high-voltage lines182A and182RA and the high-voltage lines183A and183RA are disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less) between the SU110A and the battery unit120A. Because parallel two electric wires or a stranded electric wire is used, the predetermined distance is several millimeters (less than 10 millimeters).

Here, switching between the first switching element112A and the second switching element113A will be described.FIG.12is a diagram showing a connection between the SU910A and the battery unit920A in the power supply device90of the related art. With reference toFIG.12,FIG.12shows a rewritten version of the portion of the SU910A and the battery unit920A through which the high voltage current flows in the configuration shown inFIG.2. Therefore, the explanation that overlaps with the explanation with reference toFIG.2is not repeated.

FIG.13is a diagram showing a connection between the SU110A and the battery unit120A in the specific example according to the fourth embodiment. With reference toFIG.13,FIG.13shows a rewritten version of the portion of the SU110A and the battery unit120A through which the high voltage current flows in the configuration shown inFIG.11. Therefore, the explanation that overlaps with the explanation with reference toFIG.11is not repeated.

When the first switching element112A and the second switching element113A are turned on at the same time, this causes a short-circuit state. Therefore, when one of the first switching element112A and the second switching element113A is turned on, the other is turned off.

FIG.14is a first diagram for explaining switching between the first switching element112A and the second switching element113A of the SU110A in the specific example according to the fourth embodiment. With reference toFIG.14, when the first switching element112A is on and the second switching element113A is off, the positive terminal118PA and the negative terminal118NA are connected without passing through the battery121A. That is, when the battery121A is not connected to the high-voltage line180PA connected to the positive terminal118PA and the high-voltage line180PB connected to the negative terminal118NA, the electric power of the battery121A cannot be exchanged externally of the SU110A.

The return positive terminal118PRA and the return negative terminal118NRA are directly connected by the electric path116RA. Therefore, even inside the SU110A, the electric path116A and the electric path116RA in which the currents flow in the opposite direction to each other are set to be disposed side by side with each other.

FIG.15is a second diagram for explaining switching between the first switching element112A and the second switching element113A of the SC110A in the specific example according to the fourth embodiment. With reference toFIG.15, when the first switching element112A is off and the second switching element113A is on, the positive terminal118PA and the negative terminal118NA are connected while passing through the battery121A. That is, when the battery121A is connected in series to the high-voltage line180PA connected to the positive terminal118PA and the high-voltage line180PB connected to the negative terminal118NA, the electric power of the battery121A can be exchanged externally of the SU110A.

The return positive terminal118PRA and the return negative terminal118NRA are directly connected to each other by a first electric path in which the electric path115RA, the high-voltage line182RA, the electric path123, the high-voltage line183RA, and the electric path116RA are connected in this order. Therefore, even inside the SU110A and the battery unit120A, a second electric path in which the electric path115A that is an electric path passing through the battery121A, the high-voltage line182A, the battery121A, the high-voltage line183A, and the electric path116A are connected in this order and the first electric path described above that does not pass through the battery121A are set to be disposed side by side with each other.

As described above, even inside the SU110A and the battery unit120A, the electric paths in which the currents flow in the opposite direction to each other are set to be disposed side by side with each other. Therefore, it is possible to contribute to reduction of the area of the closed loop of the power supply device10.

Fifth Embodiment

The SU110F in the fourth embodiment has a long distance from the SU110G. Therefore, in a fifth embodiment, the SU110F is connected to the SU110N.

FIG.16is a schematic diagram showing the outline of the configuration of a power supply device10A according to the fifth embodiment. With reference toFIG.16, connections of the SUs110A to110F are similar to the connections according to the fourth embodiment shown inFIG.9.

The SU110F and the SU110N are connected by a high-voltage line180PX on the positive electrode side and a high-voltage line180NX on the negative electrode side. The SU110N and the SU110M (not shown) are connected by a high-voltage line180PW on the positive electrode side and a high-voltage line180NW on the negative electrode side. The SU110H (not shown) and the SU110H are connected by a high-voltage line180PV on the positive electrode side and a high-voltage line180NV on the negative electrode side. The SU110H and the SU110G are connected by a high-voltage line180PU on the positive electrode side and a high-voltage line180NU on the negative electrode side. Two terminals of the SU110G that are not connected to the SU110H are connected by a high-voltage line180T as a termination process.

With this configuration, in addition to the effect of the fourth embodiment, the length of the high-voltage line inside the power supply device10A can be shortened. Therefore, the area of the closed loop in the power supply device10A can be further reduced.

Sixth Embodiment

In the fourth embodiment, the high-voltage line in the power supply device10is routed using parallel two electric wires. In a sixth embodiment, the high-voltage line in a power supply device108is routed using three parallel electric wires.

FIG.17is a schematic diagram showing the outline of the configuration of the power supply device10B according to the sixth embodiment. With reference toFIG.17, the power supply device10B includes SUs1110A to110N. InFIG.17, the batteries of the battery units are also included in the SUs1110A to1110N. The SUs1110A to1110N include, in addition to the configuration of the SUs210A to210N shown inFIG.5, two sets of two terminals for connecting the high-voltage lines and two electric paths that directly connect the two sets of two terminals.

The SU1110A and the SU1110B are connected by the high-voltage line180PB on the positive electrode side, the high-voltage line180NB on the negative electrode side, and a return path line180RB. Similarly, the SUs1110B to1110M and the SUs1110C to1110N adjacent thereto are connected by the high-voltage lines180PC to180PN on the positive electrode side, the high-voltage lines180NC to180NN on the negative electrode side, and return path lines180RC to180RN, respectively. The positive electrode terminal (not shown) and the SU110A of the power supply device10B are connected by the high-voltage line180PA on the positive electrode side. The negative electrode terminal (not shown) and the SU1110A of the power supply device10B are connected by the high-voltage line180NA on the negative electrode side. A ground (not shown) and the SU1110A of the power supply device10B are connected by a return path line180RA. Two terminals of the SU1110N that are not connected to the SU1110M are connected by the high-voltage line180Z as a termination process.

The combinations of the high-voltage lines180PA to180PN, the high-voltage lines180NA to180NN, and the return path lines180RA to180RN are each configured using parallel three electric wires. A stranded electric wire obtained by twisting three electric wires may be used instead of the parallel three electric wires.

Because parallel three electric wires or a stranded electric wire is used, the high-voltage lines180PB to180PN on the positive electrode side and the high-voltage lines180NB to180NN on the negative electrode side are disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less) between the SUs1110A to1110M and the SUs1110B to1110N adjacent thereto. Because the parallel three electric wires or a stranded electric wire is used, the predetermined distance is several millimeters (less than 10 millimeters). Further, the high-voltage line180PA on the positive electrode side and the high-voltage line180NA on the negative electrode side that are connected to the positive electrode terminal and the negative electrode terminal, respectively, are also set to be disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less).

With this configuration, the power supply device10B according to the sixth embodiment has the area of the closed loop that is significantly smaller than the area of the closed loop of the power supply device90of the related art shown inFIG.4(the dotted hatched portion inFIG.4). For example, the area of the closed loop can be reduced to one-tenth or smaller. When the area of the closed loop can be reduced to x % (0<x<100) as compared with the case of the related art, the electric field strength Ed (V/m) of the radiation due to the normal mode current can be reduced to x %.

Further, the current generated by the electric field and the magnetic field generated by the high-voltage lines180PA to180PN on the positive electrode side and the high-voltage lines180NA to180NN on the negative electrode side flows to the ground through the return path lines180RA to180RN. Therefore, radiation due to the closed loop can be weakened.

Seventh Embodiment

In the sixth embodiment, the high-voltage line in the power supply device10B is routed using three parallel electric wires. Ina seventh embodiment, the high-voltage line in a power supply device10C is routed using a shielded wire including two core wires.

FIG.18is a diagram showing the outline of the structure of a shielded wire180S according to the seventh embodiment. With reference toFIG.18, the shielded wire180S is an electric wire in which high-voltage lines187and188are covered by a shield composed of metal foil, braid, or the like.

FIG.19is a schematic diagram showing the outline of the configuration of the power supply device10C according to the seventh embodiment. With reference toFIG.19, the power supply device10C includes the SUs1110A to1110NFIG.19, the batteries of the battery units are also included in the SUs1110A to1110N. The SUs1110A to1110N include, in addition to the configuration of the SUs210A to210N shown inFIG.5, two sets of two terminals for connecting the high-voltage lines and two electric paths that directly connect the two sets of two terminals.

The SU1110A and the SU1110B are connected by a shielded wire180SB. Similarly, the SUs1110B to1110M and the SUs1110C to1110N adjacent thereto are connected by shielded wires180SC to180SN. The positive electrode terminal (not shown) and the negative electrode terminal (not shown) of the power supply device10C and the SU1110A are connected by a shielded wire180SA. Two terminals of the SU1110N that are not connected to the SU1110M are connected by the high-voltage line180Z as a termination process. The shield of any of the shielded wires180SA to180SN may be connected to the ground (not shown) of the power supply device10C.

Because the shielded wires180SB to180SN are used, the high-voltage lines on the positive electrode side and the high-voltage lines on the negative electrode side, both included in the shielded wires180SB to180SN, are disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less) between the SUs1110A to1110M and the SUs1110B to1110N adjacent thereto. Because the shielded wires are used, the predetermined distance is several millimeters (less than 10 millimeters). Further, the high-voltage line on the positive electrode side and the high-voltage line on the negative electrode side that are both included in the shielded wire180SA and connected to the positive electrode terminal and the negative electrode terminal, respectively, are also set to be disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less).

With this configuration, the power supply device10C according to the seventh embodiment has the area of the closed loop that is significantly smaller than the area of the closed loop of the power supply device90of the related art shown inFIG.4(the dotted hatched portion inFIG.4). For example, the area of the closed loop can be reduced to one-tenth or smaller. When the area of the closed loop can be reduced to x % (0<, x<100) as compared with the case of the related art, the electric field strength Ed (V/m) of the radiation due to the normal mode current can be reduced to x %.

Further, the electric field and the magnetic field generated by the high-voltage lines on the positive electrode side and the high-voltage lines on the negative electrode side, both included in the shielded wires180SA to180SN, are shielded by the shield. Therefore, the radiation due to the closed loop can be weakened.

Eighth Embodiment

In the specific example of the fourth embodiment, as shown inFIG.11, the combination of the high-voltage line182A and the high-voltage line182RA and the combination of the high-voltage line183A and the high-voltage line183RA, both connecting the SU110A and the battery unit120A, are each composed of two electric wires. In an eighth embodiment, a shielded wire is used instead of the two electric wires.

FIG.20is a diagram showing a connection between the SU110A and the battery unit120A according to the eighth embodiment. With reference toFIG.20, the battery positive electrode connection terminal117PA and the return battery positive electrode connection terminal117PRA of the SU110A and the positive electrode terminal122PA and the return positive electrode terminal122PRA of the battery unit120A are connected by a shielded wire182SA.

The battery negative electrode connection terminal117NA and the return battery negative electrode connection terminal117NRA of the SU110A and the negative electrode terminal122NA and the return negative electrode terminal122NRA of the battery unit120A are connected by a shielded wire183SA. The shields of the shielded wires182SA and183SA may be connected to the ground (not shown).

Because the shielded wires182SA to183SA are used, the high-voltage lines on the positive electrode side and the high-voltage lines on the negative electrode side, both included in the shielded wires182SA and183SA, are disposed side by side with each other (for example, in a state in which high-voltage lines are close to each other by a predetermined distance or less) between the SU110A and the battery unit120A. Because the shielded wires are used, the predetermined distance is several millimeters (less than 10 millimeters).

Further, the electric field and the magnetic field generated by the high-voltage lines on the positive electrode side and the high-voltage lines on the negative electrode side, both included in the shielded wires182SA and183SA, are shielded by the shield. Therefore, the radiation due to the closed loop can be weakened.

EXAMPLES

Next, the simulation results of the above-described embodiments will be described.FIG.21is a first diagram showing an example of a model in which the SUs910A to910N, the battery units920A to920N, and the high-voltage lines980A to980N and980Y (hereinafter referred to as “high-voltage line980”) of the power supply device90of the related art are disposed.FIG.22is a second diagram showing an example of a model in which the SUs910A to910N, the battery units920A to920N, and the high-voltage line980of the power supply device90of the related art are disposed. A model in which the power supply device90described with reference toFIG.1is disposed on shelf boards70A to70E will be described with reference toFIGS.21and22. The SCU900, the SUs910A to910F, and the battery units920A to920F are disposed on the third shelf board70C from the bottom as shown in the drawings. The SUs910G to910N and the battery units920G to920N are disposed on the second shelf board70D from the bottom as shown in the drawings. The high-voltage line980is routed among the SUs910A to910N so as to establish the connection state shown inFIG.1.

FIG.23is a diagram showing an example of a model in which the high-voltage line980of the power supply device90of the related art is disposed. With reference toFIG.23,FIG.23omits the SUs910A to910N and the battery units920A to920N fromFIGS.21and22.FIG.24is a schematic diagram showing an example of a model in which the high-voltage line980of the power supply device9) of the related art is disposed, as viewed from the front (the front side of the drawing). With reference toFIG.24, it is assumed that a current source80that generates simulation current flowing through the high-voltage line980is provided in the middle of the high-voltage line980. The current source80generates current in which high-frequency current generated due to the period F of the gate signal and the delay time is superimposed on the current generated by the electric power output by the power supply device90.

FIG.25is a diagram showing an example of a model in which the high-voltage lines180A to180N (hereinafter referred to as “high-voltage lines180”) of the power supply device10according to the fourth embodiment are disposed. With reference toFIG.25,FIG.25is a diagram corresponding toFIG.23relating to the power supply device90of the related art. Specifically, the SCU100, the SUs110A to110F, and the battery units120A to120F are disposed on the third shelf board70C from the bottom. The SUs110G to110N and the battery units120G to120N are disposed on the second shelf board70D from the bottom. The high-voltage line180is routed among the SUs110A to110N so as to establish the connection state shown inFIG.10.FIG.25shows the state in which, from the configuration in which the SCU100, the SUs110A to110N, the buttery units120A to120N, and the high-voltage line180are disposed, the components except for the high-voltage line180are omitted.

FIG.26is a schematic diagram showing an example of a model in which the high-voltage line180of the power supply device10according to the fourth embodiment is disposed, as viewed from the front (the front side of the drawing). With reference toFIG.26, it is assumed that the same current source80as inFIG.24is provided in the middle of the high-voltage line180. The current source80generates current in which the high-frequency current generated due to the period F of the gate signal and the delay time is superimposed on the current generated by the electric power output by the power supply device10.

FIG.27is a diagram showing a magnetic field distribution by the high-voltage line980of the power supply device90of the related art.FIG.28is a diagram showing a magnetic field distribution by the high-voltage line180of the power supply device10according to the fourth embodiment. InFIGS.27and28, the directions of the arrows arranged in a grid indicate the directions of the magnetic field at the positions where the respective arrows are located, and the size and color intensity of each arrow indicate the strength of the magnetic field at the position where the arrow is located. As shown inFIGS.27and28, the case where the two electric wires as the high-voltage line180are disposed side by side as in the fourth embodiment has a narrower range in which the strength of the magnetic field becomes relatively stronger and the overall strength of the magnetic field is weaker, as compared with the case of the related art where the electric wires as the high-voltage line180are not disposed side by side. The fourth embodiment has been shown as an example here. The same applies to the other embodiments.

FIG.29is a diagram showing an electric field distribution by the high-voltage line980of the power supply device90of the related art.FIG.30is a diagram showing an electric field distribution by the high-voltage line180of the power supply device10according to the fourth embodiment. InFIGS.29and30, the directions of the arrows arranged in a grid indicate the directions of the electric field at the positions where the respective arrows are located, and the size and color intensity of each arrow indicate the strength of the electric field at the position where the arrow is located. As shown inFIGS.29and30, the case where the two electric wires as the high-voltage line180are disposed side by side as in the fourth embodiment has a narrower range in which the strength of the electric field becomes relatively stronger and the overall strength of the electric field is weaker, as compared with the case of the related art where the two electric wires as the high-voltage line180are not disposed side by side. The fourth embodiment has been shown as an example here. The same applies to the other embodiments.

SUMMARY

(1) As shown inFIGS.5,7,8,9to11, and13to20, the power supply devices10,10A to10C, and20A to20C can charge and discharge electric power. The high-voltage lines180PA to180PN,280PA to280PN, etc. (hereinafter referred to as “first high-voltage line”) for exchanging the electric power externally, and the high-voltage lines180NA to180NN,280N, etc. (hereinafter referred to as “second high-voltage line”) for applying current flowing in the direction opposite to the first high-voltage lines while exchanging the electric power externally, a plurality of batteries121A to121N, etc. (hereinafter, simply referred to as “batteries”), a plurality of the SUs110A to110N,210A to210N,1110A to1110N (hereinafter, simply referred to as “SUs”) that is provided corresponding to the batteries, switches the connection state of the batteries to the first high-voltage lines, and is disposed in a circle, and the SU100that controls the SUs.

As shown inFIGS.2,11, and13to15, the SU can switch between a first state in which the battery corresponding to the SU is connected in series to the first high-voltage line and a second state in which the battery is not connected to the first high-voltage line. As shown inFIGS.1and10, the SCU100controls the SUs to switch to the first state or the second state in accordance with the voltage of the electric power to be charged and discharged. One of the first high-voltage line and the second high-voltage line is disposed side by side with the other between the adjacent SUs.

With this configuration, one of the first high-voltage line and the second high-voltage line is set to be disposed side by side with the other between the adjacent SUs. For this reason, the closed loop surrounded by the power lines can be reduced as compared with the case where the adjacent SUs are connected to each other by only one power line of the outward path and the return path and the other power line extends along another path in which the other power line is not disposed side by side with the one power line, whereby the radiation can be reduced. As a result, the effect of radiation on the surroundings can be reduced.

(2) As shown inFIGS.9to11,16,17, and19, the adjacent SUs are connected by the first high-voltage line and the second high-voltage line. With this configuration, the area of the closed loop surrounded by the power lines can be further reduced as compared with the case where the adjacent SUs are connected by only either of the first high-voltage line or the second high-voltage line, whereby the radiation can be further be reduced. As a result, the effect of radiation on the surroundings can be further reduced.

(3) As shown inFIG.11, the power supply devices10,10A to10C, and20A to20C further include the high-voltage line182A that connects the SU110A and the positive electrode terminal122PA of the battery121A corresponding to the SU110A, and the high-voltage line183A that connects the SU110A and the negative electrode terminal122NA of the battery121A corresponding to the SU110A. The SU110A further includes: the positive terminal118PA for connecting the high-voltage line180PA connected to the SU on one adjacent side; the negative terminal118NA for connecting the high-voltage line180PB connected to the SU on the other adjacent side; the battery positive electrode connection terminal117PA for connecting the high-voltage line182A connected to the corresponding battery121A; the battery negative electrode connection terminal117NA for connecting the high-voltage line183A connected to the corresponding battery121A; the first electric path that connects the positive terminal118PA and the battery positive electrode connection terminal117PA; the second electric path that connects the negative terminal118NA and the battery negative electrode connection terminal117NA; a bypass electric path that connects the positive terminal118PA and the negative terminal118NA without passing through the battery121A; the first switching element112A that is provided in the middle of the bypass electric path and opens and closes the bypass electric path; and the second switching element113A that is provided in the middle of the first electric path or the second electric path and opens and closes the first electric path or the second electric path. As shown inFIGS.13to15, the first state is a state in which the first switching element112A is closed and the second switching element113A is opened, and the second state is a state in which the first switching element112A is opened and the second switching element113A is closed.

With this configuration, the battery121A can be connected in series or not connected to the high-voltage lines180PA and180PB by simply opening and closing the first switching element112A and the second switching element113A.

(4) As shown inFIG.11, the SU110A further includes: the return positive terminal118PRA for connecting the high-voltage line180NA connected to the SU on one adjacent side; the return negative terminal118NRA for connecting the high-voltage line180NB connected to the SU on the other adjacent side; and a return electric path that connects the return positive terminal118PRA and the return negative terminal118NRA.

With this configuration, the SU110A including the first and second electric paths through which the current of the high-voltage lines180PA and180PB flows includes the return electric path through which the current of the high-voltage lines180NA and180NB flows. Therefore, the area of the closed loop can be further reduced, and the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

(5) As shown inFIG.11, the power supply devices10,10A to10C further includes: the high-voltage line182RA for applying current flowing in the direction opposite to the high-voltage line182A; and the high-voltage line183RA for applying current flowing in the direction opposite to the high-voltage line183A. The high-voltage lines182A and182RA are disposed side by side with each other, and the high-voltage lines183A, and183RA are disposed side by side with each other.

With this configuration, the high-voltage line182RA and the high-voltage line183RA for applying current flowing in the opposite direction are connected in a state in which the high-voltage lines182RA and183RA are disposed side by side with the high-voltage line182A and the high-voltage line183A that connect the SU110A and the battery121A. Therefore, the area of the closed loop can be further reduced, and the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

(6) As shown inFIG.20, the high-voltage lines182A and182RA are configured by the shielded wire182SA including the high-voltage lines182A and182RA as core wires. The high-voltage lines183A and183RA are configured by the shielded wire183SA including the high-voltage lines183A and183RA as core wires. With this configuration, the shield of the shielded wires182SA and183SA serves as the return lines of the high-voltage lines182A and182RA and the high-voltage lines183A and183RA, whereby the common components of the high-voltage lines182A and182RA and the high-voltage lines183A and183RA can be returned to the ground. Therefore, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

The first power line and the second power line may be twisted together between the switching units adjacent to each other. With this configuration, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

(7) As shown inFIG.17, the adjacent SUs may be connected by the return path lines180RA to180RN, in addition to the high-voltage lines180PA to180PN and the high-voltage lines180NA to180NN. With this configuration, the common components of the high-voltage lines180PA to180PN and the high-voltage lines180NA to180NN can be returned to the ground by the return path lines180RA to180RN. Therefore, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.

(8) As shown inFIGS.18and19, the adjacent SUs may be connected by the shielded wire180S including the high-voltage lines187and188as core wires. With this configuration, the shield189of the shielded wire18S serves as the return line of the high-voltage lines187and188, whereby the common component of the high-voltage lines187and188can be returned to the ground. Therefore, the radiation can be further reduced. As a result, the effect of radiation on the surroundings can be further reduced.