JP2018074889A - Electrical power system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrical power system capable of properly controlling transmission of electric power from two power sources while achieving miniaturization, weight saving or cost reduction.SOLUTION: A voltage conversion unit 3 of an electrical power system A1 comprises a plurality of voltage conversion parts 15a1-15b2, and a control part 4. The voltage conversion unit 3 has the voltage conversion parts 15a1-15a2 of a first conversion group capable of inputting only electric power of a first power source 1, and the voltage conversion parts 15b1 and 15b2 of a second conversion group capable of inputting both the electric power of the first power source 1 and the electric power of the power source 2. The control part 4 can control the first and second conversion groups in respective different control modes.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power supply system having two power supplies and a plurality of voltage conversion units.

  Conventionally, as this type of power supply system, as shown in, for example, Patent Documents 1 to 3, a power supply system including a fuel cell and a rechargeable battery as two power sources is generally known. In the systems shown in these Patent Documents 1 to 3, a converter that performs voltage conversion of the fuel cell and a converter that performs voltage conversion of the battery are provided, and electric power is supplied to an electric load such as an electric motor via these converters. Supplied.

  In this case, the converter on the fuel cell side employs a multiphase converter having a plurality of voltage converters for the purpose of increasing the power transmission efficiency.

Japanese Patent No. 5447520 Japanese Patent No. 5751329 Japanese Patent No. 5892367

  In the conventional power supply systems as seen in Patent Documents 1 to 3, a separate converter is provided for each of the two power supplies, and as a converter on one power supply (fuel cell) side, A converter is used.

  Such a power supply system can perform power control in a variety of ways, but requires a large number of entire circuit components including converters corresponding to each of the two power supplies. For this reason, the size, weight, or cost of the power supply system is increased, and it is difficult to reduce them.

  In addition, operating the converters corresponding to each of the two power supplies in the maximum output state is generally only temporary, so that each converter is operated in a state where there is sufficient remaining power. Cheap. For this reason, the cost performance of the power supply system tends to be low.

  The present invention has been made in view of such a background, and provides a power supply system capable of appropriately controlling power transmission of two power supplies while realizing miniaturization, weight reduction, or cost reduction. Objective.

  Moreover, it aims at providing the transport equipment provided with this power supply system.

In order to achieve the above object, the power supply system of the present invention provides
A first power source and a second power source;
The first power input unit and the second power input unit to which the power of the first power source and the second power source are respectively input, and the power of the first power source and the second power source are the first power input unit or the second power input. And a plurality of voltage converters each configured to be able to output power obtained by converting the voltage of the input power, the plurality of voltage converters being a common power output unit A voltage conversion unit connected in parallel to the power output unit so as to be able to output power to an external electric load;
A control unit having a function of controlling the voltage conversion unit,
The voltage conversion unit includes a first conversion group that is a set of one or more voltage conversion units that can receive only power of a first power supply of the first power supply and the second power supply, and the first power supply. And a second conversion group that is a set of one or more voltage conversion units that can receive power from both of the second power sources,
The control unit is configured to be able to control the first conversion group and the second conversion group in different control modes (first invention).

  In the present invention, more specifically, “the power of both the first power supply and the second power supply can be input” to any one of the plurality of voltage conversion units. Each can be input to the voltage converter at different timings or simultaneously.

  According to the first invention, the voltage conversion unit of the first conversion group is used as a voltage conversion unit that performs voltage conversion of only the power of the first power source, that is, a voltage conversion unit dedicated to the first power source. Can do.

  On the other hand, the voltage conversion unit of the second conversion group is a voltage conversion unit that performs voltage conversion of the power of both the first power source and the second power source, that is, is shared by both the first power source and the second power source. It can be used as a voltage converter.

  Then, the control unit can control the first conversion group and the second conversion group in different control modes. For this reason, the transmission of power from the first power supply can be controlled in a wider mode than the transmission of power from the second power supply. The power transmission of the second power source is controlled separately from the power transmission of the first power source in a state where the power transmission of the first power source is performed using the voltage conversion unit of the first conversion group. obtain.

  As described above, while sharing a part of the plurality of voltage conversion units (voltage conversion units of the second conversion group) with the first power supply and the second power supply, the transmission of the power of each of the first power supply and the second power supply is performed. Can be controlled. Therefore, according to the power supply system of the first invention, it is possible to appropriately control the power transmission of the two power supplies while realizing a reduction in size, weight, or cost.

  In the first invention, since the first power supply can input power to more voltage conversion units than the second power supply, the first power supply and the second power supply have their characteristics and the present invention. It is preferable to use a power source having good compatibility with the power source system.

  For example, as the first power source and the second power source, the first power source has higher energy density than the second power source, and the second power source has higher output density than the first power source. It is preferable to employ power supplies having different characteristics (second invention).

  In the first invention or the second invention, more specifically, for example, a fuel cell can be adopted as the first power source, and a capacitor can be adopted as the second power source (third invention).

  According to these 2nd invention or 3rd invention, it becomes possible to supply electric power to the electric load using the first power source as a main power source and the second power source as an auxiliary power source. As a result, it is possible to supply electric power to the electric load in a wide range while sufficiently extending the period during which electric power can be supplied to the electric load.

  In the first to third aspects of the invention, the voltage conversion unit includes a first A energization path that supplies power from the first power input unit to the voltage conversion unit belonging to the first conversion group, and the second conversion group. A first B energization path for supplying power from the first power input section to the voltage conversion section to which it belongs, and a second energization path for supplying power from the second power input section to the voltage conversion section belonging to the second conversion group And the first B energization path includes a diode that blocks power transmission in a direction opposite to the direction from the first power input unit toward the voltage conversion unit belonging to the second conversion group. The second power source is connected to the second current path via the diode so as to be prevented from being transmitted from the second current path to the first power input unit through the first current path. (4th shot) ).

  According to the fourth aspect of the invention, during operation of the voltage conversion unit of the second conversion group, the power of the first power source or the second power source can be input to the first voltage conversion unit without any trouble, while the first conversion It is possible to reliably prevent the power of the two power supplies from being supplied to the voltage conversion unit of the group or the power of the second power supply to the first power supply side.

  As a result, the voltage conversion unit of the first conversion group and the voltage conversion unit of the second conversion group can be appropriately operated with high reliability.

  In the fourth invention, it is preferable that the first B energization path further includes a switch element capable of interrupting energization in the first B energization path (fifth invention).

  According to this, it becomes possible to cut off the input of the electric power from the first power source appropriately and reliably to the voltage conversion unit of the second conversion group. As a result, it can be easily realized that the voltage conversion unit of the second conversion group is appropriately used as a dedicated voltage conversion unit for the second power supply.

  In the first to fifth inventions, the power transmission of the first power source and the second power source can be performed in various ways by the control process as described below.

  That is, for example, the control unit inputs the power of the first power source from the first power input unit to the voltage conversion unit of the first conversion group, and from the second power input unit to the second conversion group. In a state where the power of the second power source is input to the voltage conversion unit, the voltage conversion unit of the first conversion group is operated to perform voltage conversion of the input power, and the second conversion group A first control process for supplying the power of both the first power source and the second power source to the electric load from the power output unit by operating the voltage conversion unit to output the input power as it is. It may be configured to have a function to execute (sixth invention).

  According to this, it becomes possible to supply the electric power of the second power supply to the electric load as an auxiliary while supplying the electric power of the first power source as the main electric power for the operation of the electric load. In addition, since the voltage conversion operation of the voltage conversion unit of the second conversion group is not performed, power loss in the voltage conversion unit of the second conversion group can be reduced.

  In particular, by applying the sixth invention to the second invention or the third invention, the respective capacities of the first power supply and the second power supply can be suitably utilized.

  In the sixth aspect of the invention, when the electric load is, for example, an electric motor, the control unit is configured such that the required acceleration or required driving force of the electric motor is smaller than a predetermined threshold value, or in the cruise operation state of the electric motor. The first control process is preferably configured to have a function (seventh invention).

  According to this, it becomes possible to efficiently supply relatively little electric power to the electric load.

  In the first to seventh inventions, for example, the control unit inputs the power of the first power source from the first power input unit to the voltage conversion unit of the first conversion group, and the second power. In the state where the power of the second power source is input from the input unit to the voltage conversion unit of the second conversion group, the voltage conversion unit of each of the first conversion group and the second conversion group is set to the voltage of the input power. By performing the operation so as to perform the conversion, the power control unit is configured to have a function of executing a second control process for supplying power from both the first power source and the second power source to the electric load from the power output unit. (Eighth invention)

  According to this. Since the voltage conversion units of the first conversion group and the second conversion group are operated so as to perform voltage conversion of the input power, the required electric power is supplied in a wide range to the electric load. Can do.

  In the eighth aspect of the invention, in the second control process, the control unit controls the voltage conversion unit of the first conversion group in one control mode of voltage control and current control. The voltage converter may be configured to be controlled by the other control mode of voltage control and current control (9th invention).

  “Voltage control” means feedback control for controlling the input voltage or output voltage of the voltage converter to a desired target value, and “current control” means the input current or output current of the voltage converter. This means feedback control for controlling to the target value.

  According to the ninth aspect, it is possible to control the voltage and current of the total power supplied to the electric load from both the first power source and the second power source. As a result, required electric power can be supplied to the electric load with high reliability.

  In the ninth aspect of the invention, for example, when the first power source is a fuel cell and the second power source is a battery (for example, a battery, a capacitor, etc.), the control unit performs the first control in the second control process. It is preferable that the voltage conversion unit of the conversion group is controlled by a control mode of current control, and the voltage conversion unit of the second conversion group is controlled by a control mode of voltage control (10th invention).

  According to this, the voltage conversion part of the said 1st conversion group can be controlled with the form suitable for the control mode of electric current control, ie, the transmission control of the electric power of the 1st power supply which is a fuel cell. As a result, it becomes possible to stably control power supply to the electric load with high reliability.

  In the eighth to tenth aspects of the invention, when the electric load is, for example, an electric motor, the control unit performs the first conversion group when the required acceleration or required driving force of the electric motor is greater than a predetermined threshold. Preferably, the second conversion group is configured to have a function of executing the second control process so as to cause each voltage conversion unit of the second conversion group to perform a boosting operation (11th invention).

  According to this, it becomes possible to appropriately supply relatively large power to the electric load.

  In the first to eleventh inventions, in the case where the second power source is a rechargeable battery, the control unit controls the entire power of the first power source input to the first power input unit or one of the power sources. By supplying the power from the first power input unit to the second power input unit without inputting the voltage to the voltage conversion unit of each of the first conversion group and the second conversion group. A third control process for charging the second power supply, and the voltage conversion section of the first conversion group in a state where the power of the first power supply is input from the first power input section to the voltage conversion section of the first conversion group. Is operated to cause voltage conversion of input power, and all or part of the power output from the voltage conversion unit of the first conversion group is supplied to the voltage conversion unit of the second conversion group. In the state input from the power output unit side, the voltage conversion unit of the two conversion groups is connected to the second power. By operating the power unit to output power, the power of the first power source is provided with a function of executing at least one of the fourth control processing and charging the second power source. (Twelfth invention).

  According to this, the electric power of the first power supply is appropriate. The second power can be charged. In particular, when the twelfth invention is applied to the second invention or the third invention, sufficient power can be secured with the first power supply, while the remaining power is likely to be reduced early. Depletion can be prevented.

  In the thirteenth aspect of the invention, the control unit is configured such that the voltage of power input from the first power source to the first power input unit is greater than the voltage of power input from the second power source to the second power input unit. If it is too high, it may be configured to have a function of executing the third control process (13th invention).

  According to this, the third control process can be realized using a simple circuit configuration such as the circuit configuration described in the fourth invention.

  In the twelfth or thirteenth aspect of the invention, the control unit inputs a voltage of power input from the first power source to the first power input unit from the second power source to the second power input unit. When lower than the voltage of electric power, it may be configured to have a function of executing the fourth control process (fourteenth invention).

  According to this, since the voltage conversion (boost) can be performed by the voltage conversion unit of the first conversion group or the voltage conversion unit of the second conversion group, the output voltage of the first power supply is the voltage of the second power supply. Even if the output voltage is lower than the output voltage, it is possible to appropriately charge the power of the first power source to the second power source.

  In the twelfth to fourteenth aspects of the invention, the control unit converts a part of the power of the first power source input to the first power input unit to the first conversion group when power is supplied to the electric load. By operating the voltage conversion unit of the first conversion group so as to perform voltage conversion of the input power in a state of being input to the voltage conversion unit, the power of the first power source is supplied from the power output unit. Supplying to the electric load may be configured to have a function of executing a 5a control process, which is a control process performed in parallel with the third control process (15th invention).

  According to this, power can be supplied from the first power source to the electric load in parallel with charging the power of the first power source to the second power source by the third control process.

  In the twelfth to fifteenth inventions, the control unit transfers a part of the power output from the voltage conversion unit of the first conversion group when the power is supplied to the electric load from the power output unit. Supplying the load may be configured to have a function of executing a 5b control process that is a control process performed in parallel with the fourth control process (a sixteenth aspect).

  According to this, power can be supplied from the first power source to the electric load in parallel with charging the power of the first power source to the second power source by the fourth control process. In the sixteenth aspect of the invention, the voltage conversion unit of the first conversion group transmits the combined power of the power supplied to the electric load and the power supplied to the second power supply from the first power supply.

  In the fifteenth aspect, when the electric load is, for example, an electric motor, the control unit preferably has a function of executing the 5a control process in a cruise operation state at a predetermined speed or higher of the electric motor. (17th invention).

  Similarly, in the sixteenth aspect of the invention, when the electric load is, for example, an electric motor, the control unit has a function of executing the fifth b control process in a cruise operation state at a predetermined speed or higher of the electric motor. It is preferable to have such a configuration (18th invention).

  According to these seventeenth or eighteenth inventions, the second power source can be charged while performing the power running operation of the motor with the power of the first power source while the power consumption of the motor is relatively low. In particular, when the seventeenth invention or the eighteenth invention is applied to the second invention or the third invention, it is possible to appropriately prevent depletion of the power of the second power source.

  The 17th and 18th inventions may be combined.

  In the twelfth to eighteenth aspects of the invention, when the electrical load is an electric motor capable of outputting regenerative power, the control unit outputs the regenerative power of the motor to the power output during the regenerative operation of the motor. The voltage conversion unit of the second conversion group is operated so as to output power to the second power input unit in a state where the voltage conversion unit of the second conversion group is input to the voltage conversion unit of the second conversion group. It may be configured to have a function of executing a 6a control process that is a control process performed in parallel with the third control process to charge two power sources (19th invention).

  According to this, at the time of regenerative operation of the motor, in parallel with charging the power of the first power source to the second power source by the third control process, the regenerative power generated by the motor is further converted to the power of the first power source. In addition, the second power source can be charged.

  In the twelfth to nineteenth aspects of the present invention, when the electrical load is an electric motor capable of outputting regenerative power, the control unit transmits the regenerative power to the power output unit side during regenerative operation of the motor. The regenerative power is charged from the voltage conversion unit of the second conversion group to the second power source by inputting to the voltage conversion unit of the second conversion group in parallel with the fourth control process. It may be configured to have a function of executing the 6b control process which is a control process (20th invention).

  According to this, at the time of regenerative operation of the motor, in parallel with charging the power of the first power source to the second power source by the fourth control process, the regenerative power generated by the motor is further converted to the power of the first power source. In addition, the second power source can be charged. In the twentieth invention, the voltage conversion unit of the second conversion group uses the combined power of the power input from the first power supply via the voltage conversion unit of the first conversion group and the regenerative power as the second power supply. Will be transmitted.

Moreover, the transport device of the present invention is characterized by including the power supply system according to any one of the first to twentieth inventions (a twenty-first invention).
According to this, the transport apparatus which can have the effect demonstrated by the said 1st-20th invention is realizable.

The figure which shows the structure of the power supply system of embodiment of this invention. 2A and 2B are diagrams each showing a circuit configuration of a voltage conversion unit provided in the power supply system of the embodiment. FIG. 3A is a time chart showing an aspect of switching control of the switch elements of the two voltage converters of the power supply system of the embodiment, and FIG. 3B is a switching control of the switch elements of the four voltage converters of the power supply system of the embodiment. The time chart which shows an aspect. The figure which shows typically the form of the electric power transmission by a 1st control process. The figure which shows typically the form of the electric power transmission by a 2nd control process. The figure which shows typically the form of the electric power transmission by a 3rd control process. The figure which shows typically the form of the electric power transmission by a 4th control process. The figure which shows typically the form of the electric power transmission in the 5a control process containing a 3rd control process. The figure which shows typically the form of the electric power transmission in the 5b control process containing a 4th control process. The figure which shows typically the form of the electric power transmission in the 6a control process containing a 3rd control process. The figure which shows typically the form of the electric power transmission in the 6b control process containing a 4th control process.

  An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, the power supply system A <b> 1 of the present embodiment includes a first power supply 1, a second power supply 2, a voltage conversion unit 3, and a control unit 4, from each of the first power supply 1 and the second power supply 2. The electric load 100 can be fed via the voltage conversion unit 3. The voltage conversion unit 3 is controlled by the control unit 4 so as to output power (DC power) obtained by converting the voltage of the power (DC power) input from each of the first power supply 1 and the second power supply 2. It is possible.

  The power supply system A1 is mounted on, for example, a transport device (for example, an electric vehicle or a hybrid vehicle) having an electric motor as the electric load 100. The DC power output from the voltage conversion unit 3 is converted into AC power via the inverter 5 and then supplied to the electric load 100 (hereinafter referred to as the electric motor 100).

  The electric motor 100 can also perform a regenerative operation. During this regenerative operation, the regenerative power (AC power) output from the motor 100 is converted into DC power by the inverter 5 and then the voltage conversion unit 3. Is input.

  The first power source 1 and the second power source 2 are power sources having different characteristics. Specifically, the first power source 1 is a power source having a higher energy density than the second power source 2. More specifically, the energy density is the total amount of electric energy that can be output by the power source in unit weight or unit volume. In the present embodiment, the first power source 1 is, for example, a fuel cell.

  The positive and negative output terminal portions 1p and 1n of the first power source 1 are connected to a pair of first input terminal portions 11p and 11n as a first power input portion of the voltage conversion unit 3 via a contactor 6. . In the ON state of the contactor 6, the output terminal portions 1p and 1n of the first power source 1 are electrically connected to the first input terminal portions 11p and 11n, respectively, so that the output voltage of the first power source 1 is the first. It is applied between the input terminal portions 11p and 11n.

  The second power source 2 is a power source having a higher output density than the first power source 1. The power density is the amount of electricity (the amount of electric energy per unit time or the amount of electric charge per unit time) that can be output per unit time by the power source of unit weight or unit volume. In the present embodiment, the second power source 2 is configured by a rechargeable battery such as a secondary battery such as a lithium ion battery or a nickel metal hydride battery, or a capacitor.

  The positive and negative output terminal portions 2p, 2n of the second power source 2 are connected to a pair of second input terminal portions 12p, 12n as second power input portions of the voltage conversion unit 3 via a contactor 7. . When the contactor 7 is in the ON state, the output terminal portions 2p and 2n of the second power source 2 are electrically connected to the second input terminal portions 12p and 12n, so that the output voltage of the second power source 2 is the second. It is applied between the input terminal portions 12p and 12n.

  The second input terminal portion 12n on the negative side of the second input terminal portions 12p and 12n is a common terminal portion with the first input terminal portion 11n on the negative side of the first input terminal portions 11p and 11n. There may be.

  The voltage conversion unit 3 includes the first input terminal portions 11p and 11n, the second input terminal portions 12p and 12n, and a pair of output terminal portions 13p and 13n as power output portions, and the output terminal portions 13p and 13n. In addition, an electric motor 100 (electric load) is connected via an inverter 5.

  Of the output terminal portions 13p and 13n, the negative output terminal portion 13n is the first negative input terminal portion 11n or the second input terminal portions 12p and 12n of the first input terminal portions 11p and 11n. May be a terminal portion common to the second input terminal portion 12n on the negative electrode side.

  The voltage conversion unit 3 converts the electric power input from the first power source 1 to the first input terminal portions 11p and 11n or the electric power voltage input from the second power source 2 to the second input terminal portions 12p and 12n. Is generated between the output terminal portions 13p and 13n and can be output.

  More specifically, the voltage conversion unit 3 is a multiphase DC / DC converter having a plurality (four in the present embodiment) of voltage conversion units 15a1, 15a2, 15b1, and 15b2. The voltage conversion unit 3 includes a capacitor C1 connected between the first input terminal portions 11p and 11n and the second input terminal portions 12p and 12n in addition to the voltage conversion portions 15a1, 15a2, 15b1 and 15b2. A capacitor C2 connected in between, a capacitor C3 and a resistor R3 connected in parallel between the output terminal portions 13p and 13n, and diodes D3 and D4 and a switch element S4 interposed in a conduction path 22p described later. Prepare.

  Capacitors C1 to C3 smooth the voltage between the first input terminal portions 11p and 11n, the voltage between the second input terminal portions 12p and 12n, and the voltage between the output terminal portions 13p and 13n, respectively. The capacitor and resistor R3 are discharge resistors for the capacitor C3.

  The voltage converters 15a1, 15a2, 15b1, and 15b2 are all switching-type voltage converters (DC / DC converters), and each have the circuit configuration shown in FIG. 2A or the circuit configuration shown in FIG. 2B. This is a voltage converter 15b. In the present embodiment, of the four voltage converters 15a1, 15a2, 15b1, and 15b2, the two voltage converters 15a1 and 15a2 are the voltage converters 15a having the circuit configuration shown in FIG. 2A, and the other two The voltage converters 15b1 and 15b2 are voltage converters 15b having the circuit configuration shown in FIG. 2B.

  As shown in FIG. 2A, the voltage conversion unit 15a (each of the voltage conversion units 15a1 and 15a2) includes a coil La as an inductor, a switch unit SD1a formed by connecting a switch element S1a and a diode D1a in parallel, and a diode D2a. And a unidirectional voltage converter configured to perform one-way power transmission and voltage conversion from the primary side terminal portions 16p and 16n to the secondary side terminal portions 17p and 17n.

  Specifically, one end of the coil La is connected to the terminal portion 16p on the high potential side of the terminal portions 16p and 16n on the primary side. In addition, the other end of the coil La is connected to the primary-side and secondary-side terminal portions 16n and 17n via the switch portion SD1a, and the secondary-side terminal portions 17p and 17n The high potential side terminal portion 17p is connected via a diode D2a.

  The switch element S1a of the switch part SD1a is composed of semiconductor switch elements such as IGBTs, FETs, and power transistors, for example, and the energizable direction is a direction from the other end of the coil La toward the terminal parts 16an and 17an on the reference potential side. is there. In addition, the forward direction of the diode D1a is opposite to the energizable direction of the switch element S1a, and the forward direction of the diode D2a is a direction from the other end of the coil La toward the terminal portion 17p.

  The voltage conversion unit 15a having such a configuration periodically turns on / off (switches) the switch element S1a, thereby increasing the DC power obtained by boosting the voltage of the DC power input to the terminal units 16p and 16n on the primary side. It is possible to output from the terminal portions 17p and 17n on the next side. In this case, it is possible to variably control the voltage step-up rate by adjusting the on / off duty of the switch element S1a.

  When the voltage conversion unit 15a maintains the switch element S1a in the off state, the voltage conversion unit 15a is connected to the primary side of the voltage conversion unit 15a with respect to power transmission in one direction from the primary side to the secondary side of the voltage conversion unit 15a. The secondary side is substantially directly connected. In this state, the DC power input to the primary side terminal portions 16p and 16n can be output as it is (without voltage conversion) from the secondary side terminal portions 17p and 17n.

  As shown in FIG. 2B, the voltage converter 15b (each of the voltage converters 15b1 and 15b2) includes a coil Lb as an inductor, a switch unit SD1b in which a switch element S1b and a diode D1b are connected in parallel, and a switch element S2b. And a switch part SD2b formed by connecting a diode D2b in parallel, and bidirectional power transmission and voltage conversion between the primary side terminal parts 16p and 16n and the secondary side terminal parts 17p and 17n. This is a bidirectional voltage converter configured to be able to be performed.

  Specifically, one end of the coil Lb is connected to the high potential side terminal portion 16p of the primary side terminal portions 16p, 16n. The other end of the coil Lb is connected to the reference potential side terminal portions 16n and 17n on the primary side and the secondary side via the switch portion SD1b, and the secondary side terminal portions 17p and 17n It is connected to the terminal part 17p of the high potential side via the switch part SD2b.

  The switch elements S1b and S2b of the switch units SD1b and SD2b are configured by semiconductor switch elements such as IGBTs, FETs, and power transistors, for example. The direction in which the switch element S1b can be energized is a direction from the other end of the coil Lb toward the terminal portions 16n and 17n, and the direction in which the switch element S2b can be energized is a direction from the terminal portion 17p toward the other end of the coil Lb. The forward direction of the diode D1b is opposite to the energization direction of the switch element S1b, and the forward direction of the diode D2b is opposite to the energization direction of the switch element S2a.

  The voltage converter 15b having such a configuration periodically turns on / off (switches) the switch element S1b so that the voltage of the DC power input to the primary side terminal portions 16p and 16n can be obtained in the same manner as the voltage converter 15a. The boosted DC power can be output from the secondary side terminal portions 17p and 17n. In this case, it is possible to variably control the voltage step-up rate by adjusting the on / off duty of the switch element S1b.

  Further, for example, in a controlled state in which the switch element S2b is turned on, the switch element S1b is periodically turned on / off (switching), whereby the DC power (for example, the electric motor) input to the secondary side terminal portions 17bp and 17bn is obtained. It is also possible to output DC power obtained by stepping down the voltage of 100 regenerative power (DC power generated through the inverter 5) from the primary side terminal portions 16p and 16n. In this case, the voltage step-down rate can be variably controlled by adjusting the on / off duty of the switch element S1b.

  In the above step-up operation or step-down operation of the voltage conversion unit 15b, switching of both the switch elements S1b and S2b is performed so that the switch elements S1a and S1b are alternately turned on (alternately off). May be performed periodically.

  In addition, when the switching elements S1b and S2b are kept in the OFF state, the voltage conversion unit 15b relates to the primary conversion of the voltage conversion unit 15b with respect to the one-way power transmission from the primary side to the secondary side of the voltage conversion unit 15b. The side and the secondary side are substantially directly connected. In this state, the DC power input to the primary side terminal portions 16p and 16n is output as it is (without voltage conversion) from the secondary side terminal portions 17p and 17n in the same manner as the voltage conversion portion 15a. It is possible.

  Further, the voltage converter 15b maintains the switch element S1b in the off state and maintains the switch element S2b in the on state, so that the bidirectional conversion between the primary side and the secondary side of the voltage converter 15b is performed. With respect to power transmission, the primary side and the secondary side of the voltage conversion unit 15b are substantially directly connected. In this state, the DC power input to one side of the primary side terminal portions 16p and 16n and the secondary side terminal portions 17p and 17n can be output as it is (without voltage conversion) from the other side. It is.

  In the present embodiment, four voltage converters 15a1, 15a2, 15b1, and 15b2 configured as described above are incorporated in the voltage conversion unit 3 in the connection form shown in FIG.

  In FIG. 1, in order to distinguish the respective components of the two voltage converters 15a (15a1, 15a2) of the circuit configuration shown in FIG. 2A, the reference numerals of the components of the voltage converter 15a1 are suffixed with “ 1 ”is added, and“ 2 ”is added to the end of the reference numerals of the components of the voltage conversion unit 15a2. For example, reference symbols D2a1 and D2a2 are assigned to the diodes D2a of the voltage converters 15a1 and 15a2, respectively.

  Similarly, in FIG. 1, in order to distinguish each component of the two voltage converters 15b (15b1, 15b2) having the circuit configuration shown in FIG. 2B, the reference numerals of the components of the voltage converter 15b1 are added at the end of the reference numerals. “1” is added, and “2” is added to the end of the reference numerals of the components of the voltage converter 15b2.

  In FIG. 1, the primary side terminal portions 16p and 16n and the secondary side terminal portions 17p and 17n of the voltage converters 15a1, 15a2, 15b1 and 15b2 are not shown.

  Referring to FIG. 1, terminal portions 16n and 17n (not shown) on the reference potential side of the four voltage converters 15a1, 15a2, 15b1 and 15b2 are respectively connected to a common wiring line 18n (reference potential line). The first input terminal portion 11n, the second input terminal portion 12n, and the output terminal portion 13n on the negative electrode side are connected to the same potential.

  Further, the high-potential side terminal portion 17p (not shown) on the secondary side of each of the four voltage conversion portions 15a1, 15a2, 15b1, and 15b2 is connected to the positive-side output terminal via a common wiring line 19p. It is connected to the same potential as the portion 13p.

  Further, the high-potential side terminal portion 16p (not shown) on the primary side of the two voltage converters 15a1 and 15a2 having the circuit configuration shown in FIG. 2A is connected to the positive-side side via the common wiring line 20p. The input terminal 11p is connected to the same potential. The wiring line 20p corresponds to the 1A energization path in the present invention.

  The voltage converters 15a1 and 15a2 are a pair in which the cores around which the coils La1 and La2 are wound are shared. That is, the coil La1 of the voltage converter 15a1 and the coil La2 of the voltage converter 15a2 are wound around a common core Cra. In this case, the coils La1 and La2 are wound around the core Cra in winding directions opposite to each other so that magnetic fluxes generated by mutual induction when energized to each other are opposite to each other.

  Further, the high-potential side terminal portion 16p (not shown) on the primary side of the two voltage conversion portions 15b1 and 15b2 having the circuit configuration shown in FIG. 2B is connected to the positive-side side via the common wiring line 21p. The two input terminal portions 12p are connected to the same potential, and are connected to the positive first input terminal portion 11p via a conduction path 22p having diodes D3 and D4 and a switch element S4. The wiring line 21p corresponds to the second energization path in the present invention, and the energization path 22p corresponds to the 1B energization path in the present invention.

  The voltage converters 15b1 and 15b2 are a pair in which the cores around which the coils Lb1 and Lb2 are wound are shared. That is, the coil Lb1 of the voltage converter 15b1 and the coil Lb2 of the voltage converter 15b2 are wound around a common core Crb. In this case, the coils Lb1 and Lb2 are wound around the core Crb in mutually opposite winding directions so that the magnetic fluxes generated by mutual induction when energized to each other are opposite to each other.

  The switch element S4 provided in the energization path 22p is configured by a semiconductor switch element such as an IGBT, FET, or power transistor. In the energization path 22p, the diode D3 is connected in series to the switch element S4, and the diode D4 is connected in parallel. In this case, the energizable direction of the switch element S4 and the forward direction of the diode D3 are directions from the first input terminal portion 11p toward the voltage conversion portions 15b1 and 15b2. Further, the forward direction of the diode D4 is opposite to the energizable direction of the switch element S4.

  Since the switching element S4 and the diodes D3 and D4 are interposed in the energization path 22p as described above, the second input terminal section 12p is connected to the first input terminal section 11p and the wiring line 21p and the energization path 22p. It is connected to the wiring line 20p.

  And in the OFF state of switch element S4 of energization path 22p, since energization path 22p is intercepted, the 2nd input terminal part 12p and the primary side of voltage conversion parts 15a1 and 15a2 are the 1st input terminal part 11p and wiring. It is electrically disconnected from the line 20p. In this state, power cannot be transmitted in any direction between the primary side of the first power supply 1 or the voltage conversion units 15a1 and 15a2 and the primary side of the second power supply 2 or the voltage conversion units 15b1 and 15b2. It will be a thing.

  Further, in the ON state of the switch element S4, it is possible to energize the diode D3 in the forward direction through the energization path 22p, while preventing energization in the reverse direction. Therefore, energization from the first input terminal portion 11p or the wiring line 20p to the primary side of the second input terminal portion 12p or the voltage converters 15b1 and 15b2 is possible, but energization in the reverse direction is blocked by the diode D3. Is done. As a result, although it is possible to transmit power from the first power source 1 to the primary side of the second power source 2 or the voltage converters 15b1 and 15b2 via the energization path 22p, the second power source 2 or the voltage converter 15b1, Power transmission from the primary side of 15b2 to the primary side of the first power supply 1 or the voltage converters 15a1 and 15a2 is blocked by the diode D3.

  Therefore, power transmission from the primary side of the second power source 2 or the voltage converters 15b1 and 15b2 to the primary side of the first power source 1 or the voltage converters 15a1 and 15a2 is not possible regardless of the on / off state of the switch element S4. It has become.

  Since the voltage conversion units 15a1, 15a2, 15b1, and 15b2 are connected to each other as described above, the secondary side (load side) of each of these voltage conversion units 15a1, 15a2, 15b1, and 15b2 is connected to the output terminal unit 13p. , 13n are connected in parallel.

  Also, the primary sides (power supply sides) of the voltage converters 15a1 and 15a2 having the circuit configuration shown in FIG. 2A are connected in parallel to the first input terminal portions 11p and 11n, and the circuit configuration shown in FIG. 2B. The primary side (power supply side) of each of the voltage conversion units 15b1 and 15b2 is connected in parallel to the second input terminal units 12p and 12n.

  Furthermore, in the ON state of the switch element S4, in addition to the voltage converters 15a1 and 15a2, the first input terminal is connected so that the primary sides of the voltage converters 15b1 and 15b2 can input the power of the first power supply 1. It will be in the state connected in parallel with respect to the parts 11p and 11n.

  The voltage conversion unit 3 of the present embodiment is configured as described above. For this reason, it is possible to input the electric power of the first power supply 1 to each of the four voltage converters 15a1, 15a2, 15b1, and 15b2. Therefore, the voltage conversion unit 3 can function as a DC / DC converter having a four-phase configuration with respect to the first power supply 1.

  In the following description, each of the voltage converters 15a1, 15a2, 15b1, and 15b2 is replaced with a first-phase voltage converter 15a1, a second-phase voltage converter 15a2, a third-phase voltage converter 15b1, Sometimes referred to as a four-phase voltage converter 15b2.

  Note that inputting power from the first power source 1 to the third-phase and fourth-phase voltage converters 15b1 and 15b2 causes the output voltage of the first power source 1 to be higher than the output voltage of the second power source 2. Under the circumstances, this is possible by controlling the switch element S4 of the energization path 22p to be in an ON state.

  The power of the second power supply 2 cannot be input to the first-phase and second-phase voltage converters 15a1 and 15a2, and only to the three-phase voltage converter 15b1 and the fourth-phase voltage converter 15b2. It is possible to input. Therefore, the voltage conversion unit 3 is configured to function as a two-phase DC / DC converter with respect to the second power supply 2.

  Thus, of the first to fourth phase voltage converters 15a1, 15a2, 15b1, and 15b2, the third phase and fourth phase voltage converters 15b1 and 15b2 are the first power source 1 and the second power source, respectively. 2 is a voltage converter that can input both powers (that is, a voltage converter shared by the first power source 1 and the second power source 2), and the voltage converter 15a1 for the first phase and the second phase. , 15a2 is a voltage converter that can input only the power of the first power supply 1 (that is, a voltage converter dedicated to the first power supply 1).

  In this case, in the pair of voltage converters 15a1 and 15a2 of the first phase and the second phase each having coils La1 and La2 wound around a common core Cra, power is input to the voltage converters 15a1 and 15a2. The power sources that can be used match each other (in this embodiment, only the first power source 1).

  Similarly, power is input to the voltage converters 15b1 and 15b2 for the third-phase and fourth-phase voltage converters 15b1 and 15b2 having the coils Lb1 and Lb2 wound around the common core Crb. The power sources that can be used coincide with each other (both the first power source 1 and the second power source 2 in this embodiment).

  In addition, since each of the third-phase and fourth-phase voltage conversion units 15b1 and 15b2 includes the switch elements S2b1 and S2b2 between the coils Lb1 and Lb2 and the output terminal unit 13p, the regenerative operation of the electric motor 100 is performed. In this case, it is possible to charge the second power supply 2 by supplying power from the output terminal section 13p, 13n to the second power supply 2 that is a capacitor via the voltage conversion section 15b1 or 15b2. ing.

  Alternatively, the power of the first power supply 1 is passed through the first-phase or second-phase voltage conversion unit 15a1 or 15a1 and the third-phase or fourth-phase voltage conversion unit 15b1 or 15b1, and then the second power supply 2 It is also possible to charge the battery.

  Further, in the ON state of the switch element S4 of the energization path 22p, the first input terminal portion 11p is electrically connected to the second input terminal portion 12p via the energization path 22p in the forward direction of the diode D3. In a situation where the output voltage of one power source 1 is larger than the output voltage of the second power source 2, the power of the first power source 1 is directly (voltage converters 15a1, 15a2, 15b1 via the conduction path 22p. , 15b2), the second power supply 2 can be charged.

  Note that the voltage converter 15b having the circuit configuration shown in FIG. 2B can be used as the first-phase and second-phase voltage converters 15a1 and 15a2 dedicated to the first power supply 1.

  However, since the first power source 1 is a power source that cannot be charged, the switch element S2 is unnecessary. Therefore, in the present embodiment, in order to reduce the size, weight, or cost of the voltage conversion unit 3, the circuit shown in FIG. 2A is used as the voltage conversion units 15a1 and 15a2 dedicated to the first power supply 1. The voltage converter 15a having the configuration is employed.

  In the present embodiment, the voltage conversion unit 3 is configured as described above. The set of voltage converters 15a1 and 15a2 for the first phase and the second phase corresponds to the first conversion group in the present invention, and the set of voltage converters 15b1 and 15b2 for the third phase and the fourth phase is This corresponds to the second conversion group in the invention.

  Supplementally, the voltage conversion unit 3 does not have to have a single structure, and may be configured by connecting a plurality of units to each other.

  In the present embodiment, the capacitors C1 to C3 and the resistor R3 are included in the voltage conversion unit 3, but the capacitors C1 to C3 and the resistor R3 are regarded as components not included in the voltage conversion unit 3. Also good.

  The contactors 6 and 7 may be regarded as components of the voltage conversion unit 3.

  The control unit 4 is configured by one or more electronic circuit units including a CPU, a RAM, a ROM, an interface circuit, and the like. The control unit 4 controls the operation of the voltage conversion unit 3 according to the implemented hardware configuration or program (software configuration) (specifically, on / off control of the switch elements S1a1, S1a2, S1b1, S1b2, S2b1, S2b2, S4). It has a function to perform.

  Various operations of the power supply system A1 of the present embodiment are realized by the control processing of the control unit 4. Below, the control process which the control part 4 performs is demonstrated. In the following description, it is assumed that the power supply system A1 of the present embodiment is mounted on, for example, an electric vehicle (hereinafter simply referred to as a vehicle) that runs using the electric motor 100 as a power source. In the following description, Vfc and Vbat are used as reference symbols for the output voltage of the first power supply 1 and the output voltage of the second power supply 2, respectively.

  The control unit 4 executes control processes (first to sixth b control processes) described below in a state where the contactors 6 and 7 are in an on state (a vehicle travelable state).

  Hereinafter, these control processes will be described.

(First control process)
In the first control process, when the output voltage Vbat of the second power source 2 is higher than the output voltage Vfc of the first power source 1 during the power running operation of the electric motor 100, the first power source 1 and the first power source 1 as shown in FIG. This is control processing for generating a relatively small driving force in the electric motor 100 while supplying electric power from both the two power sources 2 (mainly, electric power of the power source 1) to the electric motor 100.

  This first control process is performed, for example, when the required acceleration of the electric motor 100 (the required value of the rotational angular acceleration of the output shaft of the electric motor 100) or the required driving force is smaller than a predetermined threshold, or the operating speed of the electric motor 100 (the electric motor Control processing executed during powering operation in which the driving force to be generated in the electric motor 100 is relatively small, such as a cruise operation state of the electric motor 100 in a low speed region where the rotational angular velocity of the output shaft 100 is lower than a predetermined threshold. It is.

  It should be noted that the situation where the required acceleration or required driving force of the electric motor 100 is smaller than the predetermined threshold value, in other words, the situation where the required acceleration or required driving force (requested propulsive force) of the vehicle is smaller than the predetermined threshold value (the vehicle's gentle Acceleration situation).

  Further, the cruise operation state of the electric motor 100 is an operation state in which the rotational angular velocity of the output shaft of the electric motor 100 is kept substantially constant. The cruise operation state of the electric motor 100 in the low speed region where the operating speed of the electric motor 100 is lower than the predetermined threshold value is, in other words, the cruise driving state of the vehicle in the low speed region where the vehicle speed is lower than the predetermined threshold value.

  The first control process is executed as follows. That is, the control unit 4 is configured so that each of the third-phase and fourth-phase voltage conversion units 15b1 and 15b2 is in a situation where the output voltage Vbat of the second power supply 2 is higher than the output voltage Vfc of the first power supply 1. The switch elements S1b1 and S1b2 and the switch elements S2b1 and S2b2 are kept off. Note that the switch element S4 of the energization path 22p may be either on or off.

  As a result, the third-phase and fourth-phase voltage converters 15b1 and 15b2 respectively output the power of the second power supply 2 input to the primary side to the secondary side as it is (without performing voltage conversion). Directly connected. For this reason, the output voltages (secondary side voltages) of the voltage converters 15b1 and 15b2 of the third phase and the fourth phase, and thus the generated voltages of the power output units 13p and 13n, become the output voltage of the second power supply 2. The voltages are almost the same.

  In addition, the control unit 4 uses the output voltages (secondary side voltages) of the first-phase and second-phase voltage conversion units 15a1 and 15a2 to which the power of the first power supply 1 is input as the third-phase and fourth-phase voltages. The voltage converters 15a1 and 15a2 for the first phase and the second phase are boosted so as to match the output voltages of the voltage converters 15b1 and 15b2 (≈the output voltage of the second power supply 2).

  In this step-up operation, the switching elements S1a1 and S1a2 of the voltage converters 15a1 and 15a2 are periodically switched (on / off), and the output of the voltage converters 15a1 and 15a2 is adjusted by adjusting the switching duty. The voltage is controlled.

  In this case, the switching of the switching elements S1a1 and S1a2 of the voltage conversion units 15a1 and 15a2 is performed when the switching elements S1a1 and S1a2 are turned on (or turned off) as shown in FIG. 3A, for example. The period Tc is shifted by a phase corresponding to a time width (= Tc / 2) obtained by dividing the cycle Tc by the number of switch elements S1a1 and S1a2 (= 2) (that is, a phase of 180 degrees).

  By doing in this way, the ripple of the output voltage of voltage converter 15a1, 15a2 can be reduced.

  In the first control process, by operating the voltage conversion unit 3 as described above, as shown in FIG. 4, the first power supply 1 while performing the boosting operation of the voltage conversion units 15a1 and 15a2 of the first phase and the second phase. Then, electric power is supplied to the electric motor 100 from both the second power source 2 and the electric motor 100 is operated in a powering operation (powering operation with a relatively small driving force).

  In this case, the power of the first power source 1 (fuel cell) is mainly supplied to the motor 100, and the power of the second power source 2 (capacitor) is supplemented so as to compensate for the shortage of power of the first power source 1. Thus, the electric motor 100 can be supplied.

  In addition, when the energization current to the electric motor 100 is sufficiently small, only one of the voltage conversion units 15a1 and 15a2 may be caused to perform the boosting operation.

  Further, in order to control the secondary side voltage (input voltage to the inverter 5) generated in the output terminal portions 13p and 13n to the optimum voltage for operating the electric motor 100 efficiently, the third phase and the fourth phase are controlled. The switching control of the switching elements S1b1 and S2b2 of the phase voltage converters 15b1 and 15b2 may be performed.

(Second control process)
In the second control process, during the power running operation of the motor 100, relatively large power is supplied from both the first power source 1 and the second power source 2 to the motor 100 as shown in FIG. It is a control process that generates force.

  In the second control process, for example, power running operation is performed so that the required acceleration or required driving force of the electric motor 100 is larger than a predetermined threshold (threshold near the maximum value) (the electric motor 100 generates a relatively large driving force). This is a control process that is executed in a situation to be performed).

  It should be noted that the situation where the required acceleration or required driving force of the electric motor 100 is larger than the predetermined threshold value, in other words, the situation where the required acceleration or required driving force (requested propulsive force) of the vehicle is larger than the predetermined threshold value (the vehicle sudden Acceleration situation).

  The second control process is executed as follows. That is, the control unit 4 causes each of the voltage conversion units 15a1, 15a2, 15b1, and 15b2 of the first to fourth phases to be boosted while the switch element S4 of the energization path 22p is controlled to be in an on state. .

  In this case, the control unit 4 uses the output voltages (secondary side voltages) of the third-phase and fourth-phase voltage conversion units 15b1 and 15b2 to which the power of the second power supply 2 as a capacitor is input as a predetermined voltage. By executing the feedback control process so as to approach the target value, the switching duty of each of the switch elements S1b1 and S1b2 of the voltage converters 15b1 and 15b2 is determined. Then, switching (on / off) of the switch elements S1b1 and S1b2 is performed according to the duty.

  Thus, the voltage converters 15b1 and 15b2 are boosted by feedback control of voltage control.

  In addition, the control unit 4 uses the output currents of the first-phase and second-phase voltage conversion units 15b1 and 15b2 to which the power of the first power supply 1 that is a fuel cell is input as a predetermined target value (for example, an electric motor). The voltage conversion unit 15a1 is executed by executing the feedback control process so as to be close to the current requirement value of 100 and the current amount obtained by subtracting the total output current of the third and fourth phase voltage conversion units 15b1 and 15b2. , 15a2 switching duty of switching elements S1a1, S1a2 is determined. Then, switching of each of the switch elements S1a1 and S1a2 is performed according to the duty.

  Thus, the voltage converters 15a1 and 15a2 are boosted by current control feedback control.

  Here, since the first power supply 1 that is a fuel cell is in a state of outputting a relatively large current, the sensitivity of the voltage change with respect to the current change is low. , 15a2 is more suitable for current control than for voltage control.

  For this reason, in the present embodiment, the first phase and second phase voltage converters 15a1 and 15a2 to which the power of the first power source 1 is input are boosted by current control, and the power of the second power source 2 is input. The step-up operation of the third-phase and fourth-phase voltage converters 15b1 and 15b2 is performed by voltage control.

  In addition, the switching of the switching elements S1a1, S1a2, S1b1, and S1b2 of the four voltage conversion units 15a1, 15a2, 15b1, and 15b2 in the first to fourth phases is, for example, as shown in FIG. 3B. The timing at which each of S1a1, S1b1, S1a2, and S1b2 is turned on (or off) is a time width (= Tc) obtained by dividing the switching cycle Tc by the number of switch elements S1a1, S1b1, S1a2, and S1b2 (= 4). / 4) (ie, a phase of 90 deg.) Is sequentially shifted (in the order of the first phase, the third phase, the second phase, and the fourth phase).

  By doing in this way, the ripple of the output voltage of voltage converter 15a1, 15a2, 15b1, 15b2 can be reduced similarly to the case of the 1st control processing.

  In the second control process, by operating the voltage conversion unit 3 as described above, as shown in FIG. 5, while performing the step-up operation of the first to fourth phase voltage conversion units 15a1, 15a2, 15b1, and 15b2, Large electric power is supplied from both the first power source 1 and the second power source 2 to the electric motor 100, and the electric motor 100 is operated in a powering operation (powering operation with a large driving force).

  In this case, even if the output voltage of the second power supply 2 decreases during the execution of the second control process by controlling the switch element S4 of the energization path 22p to be in the ON state, Supply power to the electric motor 100 can be ensured via the phase and fourth phase voltage converters 15b1 and 15b2. In addition, the power of the first power source 1 can be charged to the second power source 2.

  Note that the switch element S4 may be turned off in a state where the output voltage Vfc of the first power supply 1 is higher than the output voltage Vbat of the second power supply 2.

(Third control process and fourth control process)
In the present embodiment, since the second power source 2 is a power storage device having a high output density, there is a risk that the power of the second power source 2 will be depleted early if the power of the second power source 2 is frequently supplied to the motor 100. .

  For this reason, the electric power of the 1st power supply 1 is charged to the 2nd power supply 2 suitably. This charging is performed by the third control process or the fourth control process.

  The third control process is a control process for charging the second power supply 2 as shown in FIG. 6, for example, in a situation where the output voltage Vfc of the first power supply 1 is higher than the output voltage Vbat of the second power supply 2. is there.

  In the third control process, the control unit 4 maintains the switch element S4 of the energization path 22p in the on state.

  In this case, since the output voltage Vfc of the first power supply 1 is higher than the output voltage Vbat of the second power supply 2, as shown in FIG. 6, the power of the first power supply 1 passes through the energization path 22p and the second power supply 2 Is charged. In this case, since the power of the first power source 1 can be charged to the second power source 2 without going through the voltage converters 15a1, 15a2, 15b1, 15b2, the power of the first power source 1 can be efficiently (with low loss), The second power source 2 can be charged.

  In FIG. 6, the power of the first power supply 1 is charged to the second power supply 2 in a situation where the power running operation or the regenerative operation of the electric motor 100 is not performed (operation stop state of the electric motor 100), such as when the vehicle is stopped. Is shown. However, as will be described later, the third control process can also be executed during the power running operation or the regenerative operation of the electric motor 100.

  On the other hand, in the fourth control process, the output voltage Vbat of the second power supply 2 is higher than the output voltage Vfc of the first power supply 1, that is, the power of the first power supply 1 is passed through the energization path 22p. In the situation where the supply to the two power sources 2 is blocked by the diode D3, for example, as shown in FIG.

  In this control process, the control unit 4 causes each of the voltage conversion units 15a1 and 15a2 of the first phase and the second phase to perform a boosting operation. In this case, for example, the control unit 4 is configured such that the output voltages (secondary side voltages) of the first-phase and second-phase voltage conversion units 15a1 and 15a2 are slightly higher than the output voltage Vbat of the second power supply 2. The switching duty of each of the switch elements S1a1 and S1a2 of the voltage converters 15a1 and 15a2 is controlled so as to be a value.

  Note that switching of the switch elements S1a1 and S1a2 is performed by shifting the phase as shown in FIG. 3A, as in the case of the first control process.

  Furthermore, the control unit 4 maintains the switch elements S1b1 and S1b2 of the third-phase and fourth-phase voltage conversion units 15b1 and 15b2 in the off state and maintains the switch elements S2b1 and S2b2 in the on state. As a result, the third-phase and fourth-phase voltage converters 15b1 and 15b2 each have a direct connection state in which the power input to the secondary side can be output from the primary side as it is (without performing voltage conversion). Become.

  Therefore, as shown in FIG. 7, the power of the first power source 1 boosted by the boosting operation of the first-phase and second-phase voltage converters 15a1 and 15a2 is converted into the third-phase and fourth-phase voltage converters 15b1. , 15b2 is transmitted from the secondary side to the primary side, and further, the second power source 2 is charged from the primary side of the voltage converters 15b1, 15b2.

  7 shows a situation where the power of the first power source 1 is charged to the second power source 2 when the electric motor 100 is stopped, such as when the vehicle is stopped, as in the case of FIG. However, as will be described later, the fourth control process can also be executed during the power running operation or the regenerative operation of the electric motor 100.

  As described above, in the situation where the output voltage Vbat of the second power supply 2 is higher than the output voltage Vfc of the first power supply 1, the power of the first power supply 1 is converted into voltage converters for the first phase and the second phase. The second power supply 2 can be charged through the 15a1 and 15a2 and the third and fourth phase voltage converters 15b1 and 15b2 in order.

  In the fourth control process, in a situation where the charging current to the second power source 2 is small, only one boosting operation of the first-phase and second-phase voltage converters 15a1 and 15a2 may be performed. Good.

  In the fourth control process, the switch element S4 of the energization path 22p may be maintained in the off state.

  Further, in the fourth control process, the step-down operation of the third-phase and fourth-phase voltage converters 15b1 and 15b2 (step-down operation for stepping down the voltage of the power input to the secondary side and transmitting it to the primary side) is performed. It is also possible. In this case, it is preferable to switch the switching elements S1b1 and S1b2 of the voltage converters 15b1 and 15b2 in a manner similar to that shown in FIG.

  Supplementally, in a state where the output voltage Vfc of the first power supply 1 is higher than the output voltage Vbat of the second power supply 2 and the switch element S4 of the conduction path 22p is maintained in the OFF state, the first phase and the second phase The second power supply 2 is charged through the voltage conversion units 15a1 and 15a2 and the third and fourth phase voltage conversion units 15b1 and 15b2 in this order (in other words, the second power supply 2 is connected by the fourth control process). It is also possible to charge).

  However, in order to reduce the power loss as much as possible, it is preferable that the power of the first power source 1 is charged to the second power source 2 via the energization path 22p by the third control process.

(5a control process and 5b control process)
As shown in FIG. 8, during the power running operation of the electric motor 100, the 5a control process supplies the electric power of the first power source 1 to the electric motor 100, and the third control process supplies the electric power of the first power source 1 to the second power. The control process for charging the power source 2 in parallel, the 5b control process, as shown in FIG. 9, during the powering operation of the electric motor 100, supplying the electric power of the first power source 1 to the electric motor 100; The fourth control process is a control process in which the power of the first power supply 1 is charged to the second power supply 2 in parallel.

  These 5a control processing and 5b control processing are, for example, situations where the required acceleration or required driving force of the electric motor 100 is small, for example, the operating speed of the electric motor 100 (the rotational angular velocity of the output shaft of the electric motor 100) is predetermined. This is a control process executed in the cruise operation state of the electric motor 100 in a high speed range that is higher than the threshold value.

  Note that the cruise operation state of the electric motor 100 in a high speed range where the operating speed of the electric motor 100 (the rotational angular speed of the output shaft of the electric motor 100) is higher than a predetermined threshold value, in other words, the vehicle speed is higher than the predetermined threshold value. The vehicle is in a cruise state at a high speed.

  The 5a control process is executed as follows. That is, the control unit 4 supplies the power of the first power source 1 through the energization path 22p by the third control process in a situation where the output voltage of the first power source 1 is higher than the output voltage of the second power source 2. In parallel with the charging of the second power source 2, the boost operation of one or more of the voltage converters 15a1, 15a2, 15b1, 15b2 is performed so that the voltage converter Electric power from the first power supply 1 is supplied to the electric motor 100.

  In this case, the control unit 4 increases the number (phase number) of voltage conversion units (hereinafter referred to as voltage conversion units to be boosted) for performing the boosting operation as the current to be supplied to the electric motor 100 increases. Selects the voltage converter for boosting operation.

  For example, when the current to be supplied to the electric motor 100 is relatively small, the control unit 4 sets the voltage of the first phase and second phase voltage conversion units 15a1 and 15a2 or the voltage of the third phase and the fourth phase. When a pair of converters 15b1 and 15b2 is selected as a voltage converter to be boosted and the current to be supplied to the motor 100 is relatively large, the first to fourth phase voltage converters 15a1, 15a2, and 15b1 , 15b2 are selected as voltage conversion units to be boosted.

  The control unit 4 then sets each of the voltage conversion units to be boosted so that the output voltage (secondary side voltage) of the voltage conversion unit to be boosted becomes a predetermined voltage necessary for the power running operation of the electric motor 100. The switching duty of the switch element S1a or S1b is controlled.

  In this case, the voltage conversion unit to be boosted is a pair of first-phase and second-phase voltage conversion units 15a1 and 15a2 or a pair of third-phase and fourth-phase voltage conversion units 15b1 and 15b2. To. Switching of each switch element (S1a1, S1a2) or (S1b1, S1b2) is performed by shifting the phase in the manner shown in FIG. 3A. Further, when the voltage converters to be boosted are the four voltage converters 15a1, 15a2, 15b1, 15b2 of the first phase to the fourth phase, the switching elements S1a1, S1a2, S1b1, S1b2 Switching is performed by shifting the phase in the manner shown in FIG. 3B.

  By executing the 5a control process including the third control process as described above, for example, as illustrated in FIG. 8, the power of the first power supply 1 is charged to the second power supply 2 through the energization path 22p. In parallel, the power of the first power supply 1 is passed through the voltage converters to be boosted (in the example shown in FIG. 8, four voltage converters 15a1, 15a2, 15b1, 15b2 of the first to fourth phases). Then, power is supplied to the electric motor 100.

  Supplementally, when the current to be supplied to the electric motor 100 is sufficiently small, only one of the voltage converters 15a1, 15a2, 15b1, and 15b2 is selected as the voltage converter to be boosted. May be.

  Alternatively, as the current to be supplied to the electric motor 100 increases, the number of voltage conversion units (number of phases) to be boosted may be increased by one. However, it is preferable to select a pair of voltage converters 15a1 and 15a2 having a common core Cra or Crb or a pair of voltage converters 15b1 and 15b2 as much as possible.

  On the other hand, the 5b control process is executed as follows. That is, the control unit 4 uses the fourth control process to change the power of the first power supply 1 and the first phase in a situation where the output voltage of the second power supply 2 is higher than the output voltage of the first power supply 1. In parallel with charging the second power source 2 through the second phase voltage converters 15a1 and 15b1 and the third and fourth phase voltage converters 15a1 and 15b1 in order, the first phase and the second phase The electric power of the first power source 1 is supplied to the electric motor 100 via the phase voltage converters 15a1 and 15a2.

  In this case, the control unit 4 causes the output voltage (secondary voltage) of the voltage conversion units 15a1 and 15a2 to be the second power supply 2 by the boost operation of the voltage conversion units 15a1 and 15a2 of the first phase and the second phase. The switching duty of each of the switch elements S1a1 and S1a2 of the voltage converters 15a1 and 15a2 is controlled so that the output voltage Vbat is higher than the output voltage Vbat and becomes a predetermined voltage necessary for the power running operation of the electric motor 100.

  Note that the switching of the switch elements S1a1 and S1a2 is executed by shifting the phase in the manner shown in FIG. 3A.

  Further, the control unit 4 maintains the switching elements S2b1 and S2b2 of the third-phase and fourth-phase voltage conversion units 15b1 and 15b2 in the ON state, and the voltage conversion units 15b1 and 15b2 perform the step-down operation. The switching duty of each switch element S1b1, S1b2 of the voltage converter 15b1, 15b2 so that the primary output voltage of the voltage converter 15b1, 15b2 is slightly higher than the output voltage of the second power supply 2 To control.

  Note that switching of the switch elements S1b1 and S1b2 is executed with the phase shifted in the manner shown in FIG. 3A.

  By executing the 5b control process including the fourth control process as described above, as shown in FIG. 9, the power of the first power supply 1 is converted into the first and second phase voltage converters 15a1 and 15b1, In parallel with charging the second power supply 2 through the voltage converters 15a1 and 15b1 of the third phase and the fourth phase in order, the voltage converter of the first phase and the second phase converts the power of the first power supply 1 Electric power is supplied to the electric motor 100 via 15a1 and 15b1.

  Supplementally, when the current to be supplied to the electric motor 100 is sufficiently small, the boost operation of only one of the first-phase and second-phase voltage converters 15a1 and 15a2 is performed, or the third-phase and The step-down operation of only one of the four-phase voltage converters 15b1 and 15b2 may be performed.

  By executing the 5a control process or the 5b control process as described above, the power of the first power supply 1 can be charged to the second power supply 2 while power is supplied from the first power supply 1 to the electric motor 100. For this reason, in the situation where the power running operation of the electric motor 100 can be performed only with the electric power of the first power source 1, the two power sources 2 can be charged to prevent the power of the second power source 2 from being depleted.

(6a control process and 6b control process)
The 6a control process includes charging the regenerative power output from the electric motor 100 to the second power source 2 as a capacitor as shown in FIG. 10 during the regenerative operation of the electric motor 100 (at the time of regenerative braking of the vehicle); In the third control process, the control process in which the electric power of the first power supply 1 is charged in the second power supply 2 and the 6b control process are performed during the regenerative operation of the electric motor 100 (at the time of regenerative braking of the vehicle). As shown in FIG. 11, the regenerative power output from the electric motor 100 is charged to the second power source 2 as a capacitor, and the power of the first power source 1 is charged to the second power source 2 by the fourth control process. This is a control process that performs this in parallel.

  The process 6a is executed as follows. That is, the control unit 4 supplies the power of the first power supply 1 by the third control process in a situation where the output voltage Vfc of the first power supply 1 is higher than the output voltage Vbat of the second power supply 2. In parallel with charging the second power supply 2 via the voltage conversion, the voltage conversion unit 15b1 and 15b2 for inputting the regenerative power of the electric motor 100 performs step-down operation of the voltage conversion unit 15b1 and 15b2 to perform the voltage conversion. The regenerative power is charged to the second power source 2 via the units 15b1 and 15b2.

  In this case, the control unit 4 maintains the switch elements S1a1 and S1a2 of the first-phase and second-phase voltage conversion units 15a1 and 15a2 in the off state.

  Further, the control unit 4 maintains the switching elements S2b1 and S2b2 of the third-phase and fourth-phase voltage conversion units 15b1 and 15b2 in the ON state, and the voltage conversion units 15b1 and 15b2 perform the step-down operation. Switching duty of each switch element S1b1, S1b2 of the voltage converter 15b1, 15b2 so that the primary side output voltage of the voltage converter 15b1, 15b2 becomes substantially the same voltage as the output voltage Vfc of the first power supply 1 To control.

  Note that switching of the switch elements S1b1 and S1b2 is executed with the phase shifted in the manner shown in FIG. 3A.

  By performing the 6a control process including the third control process as described above, the power of the first power supply 1 is charged to the second power supply 2 through the energization path 22p as shown in FIG. Thus, the regenerative power of the electric motor 100 is charged into the second power source 2 via the third-phase and fourth-phase voltage converters 15b1 and 15b2.

  Supplementally, when the voltage of the regenerative power input to the power output units 13p and 13n is controlled to be substantially the same voltage as the output voltage Vfc of the first power supply 1, the voltage converters of the third phase and the fourth phase The voltage conversion units 15b1 and 15b2 may be directly connected by maintaining the switch elements S2b1 and S2b2 of 15b1 and 15b2 in the on state and maintaining the switch elements S1b1 and S1b2 in the off state.

  On the other hand, the 6b control process is executed as follows. That is, the control unit 4 uses the fourth control process to change the power of the first power supply 1 to the first power level in a situation where the output voltage Vbat of the second power supply 2 is higher than the output voltage Vfc of the first power supply 1. In parallel with charging the second power supply 2 through the voltage converters 15a1 and 15b1 for the phase and second phase and the voltage converters 15a1 and 15b1 for the third phase and the fourth phase in order, the regeneration of the electric motor 100 is performed. The second power source 2 is charged with electric power via the third-phase and fourth-phase voltage converters 15b1 and 15b2.

  In this case, the control unit 4 causes the output voltage (secondary voltage) of the voltage converters 15a1 and 15a2 to be the voltage of the regenerative power by the boost operation of the first-phase and second-phase voltage converters 15a1 and 15a2. (Specifically, the switching elements S1a1 and S1a2 of the voltage converters 15a1 and 15a2 are set to substantially the same voltage as the voltage of regenerative power input from the electric motor 100 to the power output units 13p and 13n via the inverter 5). Control the switching duty.

  Note that the switching of the switch elements S1a1 and S1a2 is executed by shifting the phase in the manner shown in FIG. 3A.

  Further, the control unit 4 maintains the switching elements S2b1 and S2b2 of the third-phase and fourth-phase voltage conversion units 15b1 and 15b2 in the ON state, and the voltage conversion units 15b1 and 15b2 perform the step-down operation. The switching elements S1b1 and S1b2 of the voltage converters 15b1 and 15b2 are switched so that the output voltage on the primary side of the voltage converters 15b1 and 15b2 is slightly higher than the output voltage Vbat of the second power supply 2. Control the duty.

  Note that switching of the switch elements S1b1 and S1b2 is executed with the phase shifted in the manner shown in FIG. 3A.

  Supplementally, when the voltage of the regenerative power input to the power output units 13p and 13n is controlled to a voltage slightly higher than the output voltage Vbat of the second power supply 2, the voltage conversion of the third phase and the fourth phase The voltage conversion units 15b1 and 15b2 may be directly connected by maintaining the switch elements S2b1 and S2b2 of the units 15b1 and 15b2 in the on state and maintaining the switch elements S1b1 and S1b2 in the off state.

  By executing the 6a control process or the 6b control process as described above, the power of the first power supply 1 can be charged to the second power supply 2 in addition to the regenerative power during the regenerative operation of the electric motor 100. As a result, the electric power of the 2nd power supply 2 can be recovered in a short time.

  In the control process of the voltage conversion unit 3 described above, when the switching element S4 is switched from the off state to the on state, the output voltage Vfc of the first power source 1 is lower than the output voltage Vbat of the second power source 2 Thus, the inrush current can be suppressed by switching the switch element S4.

  According to the embodiment described above, the voltage conversion unit 3 includes the third-phase and four-phase voltage conversion units 15b1 and 15b2 among the first- to fourth-phase voltage conversion units 15a1, 15a2, 15b1, and 15b2. The first power supply 1 and the second power supply 2 are used in common, and the first phase and second phase voltage converters 15a1 and 15a2 can be used exclusively by the first power supply 1. For this reason, the power transmission of the first power source 1 and the second power source 2 can be appropriately controlled in various modes suitable for the characteristics of the power sources 1 and 2, and the voltage conversion unit 3 can be downsized. , Weight reduction or cost reduction can be realized.

  Also, the power of the second power source is supplied to the first and second phase voltage converters 15a1, 15a2 dedicated to the first power source 1, or the first power source 1 (fuel cell) that cannot be charged. A simple circuit configuration having the diode D3 can surely prevent it.

  As a result, protection of the 1st power supply 1 and electric power transmission of the 1st power supply 1 using the voltage conversion parts 15a1 and 15a2 of the 1st phase and the 2nd phase are realizable with high reliability.

  In addition, since the power sources that can input power to the voltage conversion units 15a1 and 15a2 having the common core Cra match each other (the first power supply 1), the voltage conversion units 15a1 and 15a2 are uncoupled from the coils La1 and La2, respectively. Performing balanced energization can be prevented as much as possible.

  Similarly, since the power sources that can input power to the voltage converters 15b1 and 15b2 having the common core Crb coincide with each other (both the first power source 1 and the second power source 2), each of the voltage converters 15b1 and 15b2 It is possible to prevent unbalanced energization of the coils Lb1 and Lb2 as much as possible.

  As a result, saturation of the cores Cra and Crb can be prevented, and the power transmission efficiency in each of the voltage converters 15a1, 15a2, 15b1, and 15b2 can be increased.

  In the embodiment described above, the core Cra of the voltage converters 15a1 and 15a2 is shared, and the core Crb of the voltage converters 15b1 and 15b2 is shared, but the cores of the voltage converters 15a1 and 15a2 are Alternatively, the cores of the voltage conversion units 15b1 and 15b2 may be different.

  Further, the voltage converter common to the first power source 1 and the second power source 2 may be one or three or more, and the voltage converter dedicated to the first power source 1 may be one or three or more. There may be.

  The second power source 2 may further include one or more voltage conversion units dedicated to the second power source 2.

  In the embodiment, the case where the electric motor 100 is adopted as the electric load has been described as an example. However, the electric load may be an electric actuator other than the electric motor 100 or the like.

  The first power source 1 may be a power source other than the fuel cell, for example, a capacitor having a larger capacity than the second power source 2. In this case, the first power source 1 may be a power source in which charging of regenerative power or charging from the second power source 2 is prohibited in order to prevent the progress of deterioration as much as possible.

  Further, the power supply system of the present invention may be mounted on a transportation device other than a vehicle (for example, a ship, a rail vehicle, an aircraft, etc.). Alternatively, the power supply system may be provided in a stationary facility.

  DESCRIPTION OF SYMBOLS 1A ... Power supply system, 1 ... 1st power supply, 2 ... 2nd power supply, 3 ... Voltage conversion unit, 4 ... Control part, 11p ... 1st input terminal part (1st power input part), 12p ... 2nd input terminal part (Second power input unit), 13p, 13n ... output terminal unit (power output unit), 15a1, 15a2, 15b1, 15b2 ... voltage conversion unit, La1, Lb1 ... coil, Cra, Crb ... core, 20p ... wiring line ( 1A energization path), 21p ... wiring line (second energization path), 22p ... energization path (1B energization path), D3 ... diode, S4 ... switch element, 100 ... electric motor (electric load).

Claims (21)

A first power source and a second power source;
The first power input unit and the second power input unit to which the power of the first power source and the second power source are respectively input, and the power of the first power source and the second power source are the first power input unit or the second power input. And a plurality of voltage converters each configured to be able to output power obtained by converting the voltage of the input power, the plurality of voltage converters being a common power output unit A voltage conversion unit connected in parallel to the power output unit so as to be able to output power to an external electric load;
A control unit having a function of controlling the voltage conversion unit,
The voltage conversion unit includes a first conversion group that is a set of one or more voltage conversion units that can receive only power of a first power supply of the first power supply and the second power supply, and the first power supply. And a second conversion group that is a set of one or more voltage conversion units that can receive power from both of the second power sources,
The power supply system, wherein the control unit is configured to control the first conversion group and the second conversion group in different control modes. The power supply system according to claim 1, wherein
The first power source and the second power source are such that the first power source has a higher energy density than the second power source, and the second power source has a higher output density than the first power source. A power supply system characterized by having different characteristics. The power supply system according to claim 1 or 2,
The first power source is a fuel cell, and the second power source is a battery. The power supply system according to any one of claims 1 to 3,
The voltage conversion unit includes a first A energization path that supplies power from the first power input unit to the voltage conversion unit belonging to the first conversion group, and the first voltage conversion unit belonging to the second conversion group. A first B energization path for supplying power from a power input unit; and a second energization path for supplying power from the second power input unit to the voltage conversion unit belonging to the second conversion group. The energization path includes a diode that blocks power transmission in a direction opposite to the direction from the first power input unit toward the voltage conversion unit belonging to the second conversion group, and the power of the second power source is the second power source. A power supply system connected to the second energization path through the diode so as to be prevented from being transmitted from the energization path through the first B energization path to the first power input unit side . The power supply system according to claim 4, wherein
The 1B energization path further includes a switch element capable of interrupting energization in the 1B energization path. The power supply system according to any one of claims 1 to 5,
The control unit inputs power of the first power source from the first power input unit to the voltage conversion unit of the first conversion group, and from the second power input unit to the voltage conversion unit of the second conversion group. In a state where the power of the second power supply is input, the voltage conversion unit of the first conversion group is operated to perform voltage conversion of the input power, and the voltage conversion unit of the second conversion group is operated. A function of executing a first control process for supplying the power of both the first power source and the second power source to the electric load from the power output unit by causing the input power to be output as it is. A power supply system configured to have a power supply system. The power supply system according to claim 6, wherein
The electrical load is an electric motor;
The control unit is configured to have a function of executing the first control process when a required acceleration or a required driving force of the electric motor is smaller than a predetermined threshold or in a cruise operation state of the electric motor. A power supply system characterized by The power supply system according to any one of claims 1 to 7,
The control unit inputs power of the first power source from the first power input unit to the voltage conversion unit of the first conversion group, and from the second power input unit to the voltage conversion unit of the second conversion group. By operating the voltage conversion units of the first conversion group and the second conversion group so as to perform voltage conversion of the input power in a state where the power of the second power supply is input, the first conversion group and the second conversion group are operated. A power supply system configured to have a function of executing a second control process for supplying power from both the first power supply and the second power supply to the electric load from the power output unit. The power supply system according to claim 8, wherein
In the second control process, the control unit controls the voltage conversion unit of the first conversion group in one control mode of voltage control and current control, and controls the voltage conversion unit of the second conversion group. And the power supply system comprised so that it may control by the other control aspect among current control. The power supply system according to claim 9, wherein
The first power source is a fuel cell, and the second power source is a capacitor;
In the second control process, the control unit controls the voltage conversion unit of the first conversion group in a control mode of current control, and controls the voltage conversion unit of the second conversion group in a control mode of voltage control. It is comprised in the power supply system characterized by the above-mentioned. The power supply system according to any one of claims 8 to 10,
The electrical load is an electric motor;
The controller is configured to cause the voltage converters of the first conversion group and the second conversion group to perform a boost operation when the required acceleration or required driving force of the electric motor is greater than a predetermined threshold. A power supply system configured to have a function of executing a second control process. The power supply system according to any one of claims 1 to 11,
The second power source is a rechargeable battery,
The controller is
Without inputting all or part of the power of the first power source input to the first power input unit to the voltage conversion units of the first conversion group and the second conversion group, from the first power input unit. A third control process for charging the second power source with the power of the first power source by supplying the second power input unit;
In the state where the power of the first power source is input from the first power input unit to the voltage conversion unit of the first conversion group, the voltage conversion unit of the first conversion group performs voltage conversion of the input power. And the whole or a part of the power output from the voltage conversion unit of the first conversion group is input to the voltage conversion unit of the second conversion group from the side of the power output unit. At least one of the fourth control process for charging the power of the first power source to the second power source by operating the voltage conversion unit of the conversion group to output power to the second power input unit. A power supply system configured to have a function of executing the control process. The power supply system according to claim 12,
The control unit, when the voltage of power input from the first power source to the first power input unit is higher than the voltage of power input from the second power source to the second power input unit, A power supply system configured to have a function of executing a third control process. The power supply system according to claim 12 or 13,
When the voltage of power input from the first power source to the first power input unit is lower than the voltage of power input from the second power source to the second power input unit, the control unit, A power supply system configured to have a function of executing a fourth control process. The power supply system according to any one of claims 12 to 14,
The control unit is configured to input a part of the power of the first power source input to the first power input unit to the voltage conversion unit of the first conversion group when supplying power to the electric load. Supplying the electric power of the first power source from the power output unit to the electric load by operating the voltage conversion unit of the first conversion group to perform voltage conversion of the input power; A power supply system configured to have a function of executing a 5a control process which is a control process performed in parallel with the third control process. The power supply system according to any one of claims 12 to 15,
The control unit supplies a part of power output from the voltage conversion unit of the first conversion group to the electric load from the power output unit when supplying power to the electric load. A power supply system configured to have a function of executing a 5b control process which is a control process performed in parallel with the four control processes. The power supply system according to claim 15, wherein
The electrical load is an electric motor;
The control unit is configured to have a function of executing the 5a control process in a cruise operation state at a predetermined speed or higher of the electric motor. The power supply system according to claim 16, wherein
The electrical load is an electric motor;
The power supply system, wherein the control unit is configured to have a function of executing the 5b control process in a cruise operation state at a speed equal to or higher than a predetermined speed of the electric motor. The power supply system according to any one of claims 12 to 18,
The electric load is an electric motor capable of outputting regenerative power,
In the regenerative operation of the electric motor, the control unit inputs the regenerative power of the electric motor from the power output unit to the voltage conversion unit of the second conversion group, and sets the voltage conversion unit of the second conversion group to the second conversion group. By operating the power input unit to output power, the 6a control process, which is a control process for performing the charging of the regenerative power to the second power source in parallel with the third control process, is executed. A power supply system configured to have a function. The power supply system according to any one of claims 12 to 19,
The electric load is an electric motor capable of outputting regenerative power,
The control unit is configured to input the regenerative power from the power output unit side to the voltage conversion unit of the second conversion group during the regenerative operation of the electric motor, thereby to convert the regenerative power into the voltage conversion unit of the second conversion group. The power supply system is configured to have a function of executing a 6b control process, which is a control process for performing the fourth control process in parallel with charging the second power supply from 1 to 2.   A transportation device comprising the power supply system according to any one of claims 1 to 20.