JP2002204536A - Power control device and control method for power supply apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize a delay in power supply to a load and effectively utilize charging power in a battery. SOLUTION: In a control method for a DC/DC converter 7 for a heavy current, which permits power generated by a fuel cell stack 1 to be supplied to the fuel cell stack 1 and a compressor motor 3, and is stored in a secondary cell 8, signals indicating command power quantity is inputted from a controller 14, load power quantity supplied to the secondary cell 8 or a drive motor 11 is computed, operational power quantity outputted from the DC/DC converter 7 for a heavy current is computed, a power quantity difference between load power quantities is computed, and operational power quantity to be outputted from the DC/DC converter 7 for a heavy current for the next time is determined based on the power quantity equivalent to the power quantity difference for supplying power to the drive motor 11 or to the secondary cell 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power control device for controlling the supply of electric power from a power supply to a load circuit in order to drive a load, and a control method of the power supply device. The present invention relates to a power control device that controls the supply of generated power to a drive motor and the like, and a control method of the power supply device.

[0002]

2. Description of the Related Art Conventionally, a fuel cell system that supplies a fuel gas containing hydrogen to a fuel cell and supplies air containing oxygen to cause the fuel cell to generate power and to drive a drive motor and the like using the generated power has been known. Are known.

In this fuel cell system, as disclosed in, for example, JP-A-7-57753, a fuel cell is supplied with fuel gas from a fuel reformer and air is supplied from an air supply device. A DC / DC converter for converting DC power generated and output from the fuel cell to AC power by constant voltage control and a flow rate of fuel gas and air supplied from the fuel reformer and the air supply device to the fuel cell. It often includes a flow rate operation control unit for controlling. In this fuel cell system, a load command instructing to drive a load such as a drive motor is input from the outside, and the power to be generated is set according to the load command.
The processing in the DC / DC converter and the flow rate calculation control unit is controlled by the set power set value.

In a conventional fuel cell system, a sudden increase in a load command is detected by detecting an output current from the fuel cell, and the rate of increase of a power set value is suppressed. As a result, the conventional fuel cell system has a function as an overcurrent preventing means for preventing an overcurrent, and also has a configuration for preventing a sudden voltage drop of the fuel cell.

The overcurrent prevention means has a current detector for monitoring the output power increase rate of the fuel cell. The increase rate of the output current of the fuel cell is obtained from the detected current of the current detector. The power set value is controlled so that the current increasing speed is maintained at the predetermined value when the predetermined value is exceeded.

[0006]

However, in the conventional fuel cell system, while the overcurrent is prevented, the delay in the power setting command and the delay in the power supplied to the load circuit are not taken into consideration. In many cases, it was not possible to extract power in accordance with the instructions. That is, in the conventional fuel cell system, when the power set value command suddenly increases, even if a command is issued to the load, the actual load may not follow the command.

Further, in the conventional fuel cell system, since it takes time to stably operate the fuel cell stack, the operation of the fuel cell with respect to the load is delayed, and the delayed power is supplied from the battery to the load. . Therefore, in the conventional fuel cell system, when the vehicle is repeatedly accelerated, the charge amount of the battery gradually decreases.

Accordingly, the present invention is to provide a power control device and a control method of a power supply device that reduce delay of power supply to a load and effectively use charging power of a battery.

[0009]

According to a first aspect of the present invention, there is provided a power control device for supplying power generated by a fuel cell to a load circuit and storing the power in a secondary battery. The generated power from the fuel cell is input, the generated power input / output means for supplying power to the load circuit or the secondary battery, and a signal input means to which a signal indicating a command power amount is input from outside, Load power calculation means for calculating the load power supplied to the load circuit from the secondary battery or the generated power input / output means, and operating power calculation for calculating the operating power output from the generated power input / output means Means, a power amount difference calculating means for calculating a power amount difference between the load power amount calculated by the load power amount calculating means and the operating power amount calculated by the operating power amount calculating means; Arithmetic means Based on the calculated amount of power corresponding to the power amount difference, determine the amount of operating power to be output next time from the generated power input / output means, and supply the power to the load circuit or the secondary battery. Control means for controlling the generated power input / output means.

[0010] In the invention according to claim 2, the control means determines an operation power amount obtained by increasing the operation power amount by the power amount difference from the load power amount, and supplies the power to the load circuit or the secondary circuit. The generated power input / output means is controlled so as to supply the battery.

According to a third aspect of the present invention, there is provided a control method of a power supply device for supplying power generated by a fuel cell to a load circuit and storing the power in a secondary battery. Inputting a signal indicating the amount of power, calculating the amount of load power supplied from the power supply device to the secondary battery or the load circuit, and calculating the amount of operation power output from the power control device Calculating the power amount difference between the load power amount and the operation power amount; and determining the next operation power amount output from the power supply device based on the power amount corresponding to the power amount difference. Supplying power to the load circuit or the secondary battery.

In the invention according to a fourth aspect, an operation power amount is determined by increasing the operation power amount by the power amount difference from the load power amount, and power is supplied to the load circuit or the secondary battery.

[0013]

According to the first aspect of the present invention, the amount of operation power to be output next time from the generated power input / output means is determined based on the amount of power corresponding to the power amount difference, and the power is transferred to the load circuit or the load circuit. Since the power is supplied to the secondary battery, the amount of power corresponding to the difference in the amount of power can be supplied to the secondary battery or the like at the time of the next power supply. Can be used effectively.

According to the second aspect of the present invention, the operating power amount is determined by increasing the operating power amount by the power amount difference from the load power amount, and the power is supplied to the load circuit or the secondary battery. The charging power of the secondary battery used at the time of power supply can be supplied to the secondary battery at the next power supply.

According to the third aspect of the present invention, the operating power to be output next time is determined based on the power corresponding to the power difference, and the power is supplied to the load circuit or the secondary battery. The electric energy corresponding to the electric energy difference can be supplied to the secondary battery or the like at the time of the next electric power supply, and the delay of the electric power supply to the load can be reduced, and the charging power of the secondary battery can be effectively used. .

According to the fourth aspect of the present invention, the operation power amount is determined by increasing the operation power amount by the power amount difference from the load power amount, and the power is supplied to the load circuit or the secondary battery. The charging power of the secondary battery used at the time of power supply can be supplied to the secondary battery at the next power supply.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is applied to, for example, a fuel cell system configured as shown in FIG.

[Configuration of Fuel Cell System] FIG. 1 shows a configuration of a fuel cell system. This fuel cell system
The fuel cell system includes a fuel cell stack 1 to which a hydrogen-containing gas and a fuel gas are supplied to generate power. The fuel cell stack 1 is composed of, for example, a plurality of fuel cell structures in which a fuel cell structure having an oxidant electrode and a fuel electrode opposed to each other with a solid polymer electrolyte membrane interposed therebetween is sandwiched by separators. The fuel cell stack 1 generates power by supplying air as an oxidant gas to the oxidant electrode side and supplying hydrogen gas as a fuel gas to the fuel electrode side, for example, as a driving source for an automobile or the like. Used.

This fuel cell system includes a compressor 2 for supplying air to the fuel cell stack 1, a compressor motor 3, a compressor motor inverter 4, and a compressor motor inverter control unit 5. In this fuel cell system, when the fuel cell stack 1 generates power, a control signal is supplied from a controller 14 to a compressor motor inverter control unit 5 to be described later, and the compressor motor inverter 4 and the compressor motor 3
Is supplied with power. Thus, in the fuel cell system, the compressor motor inverter control unit 5 controls the compressor motor inverter 4 to control the number of revolutions of the compressor motor 3 to control the amount of air supplied from the compressor 2 to the fuel cell stack 1.

Further, the fuel cell system includes a hydrogen storage device 6 for storing hydrogen gas supplied to the fuel cell stack 1. In this fuel cell system, when power is generated by the fuel cell stack 1, a control signal is supplied from the controller 14 to the hydrogen storage device 6, and the hydrogen storage device 6 controls the amount of hydrogen gas supplied to the fuel cell stack 1.

Further, the fuel cell system includes a DC / DC converter for high power 7 for inputting electric power generated by the fuel cell stack 1 and a secondary battery 8 for storing electric power generated by the fuel cell stack 1, for example, 12 [V]. 12V DC / DC converter 9 for supplying power to each unit, 12V battery 10 for storing power as power for 12V, drive motor 11 as load, and power supplied to drive motor 11 A drive motor inverter 12 and a drive motor inverter control unit 13 are provided. In this fuel cell system, the power generated from the fuel cell stack 1 is transferred to a high-power DC
The power is stored in the secondary battery 8 via the DC / DC converter 7 and stored in the 12V battery 10 via the DC / DC converter 9 for 12V. Further, in this fuel cell system, the generated electric power from the fuel cell stack 1 is supplied to the compressor motor 3 via the compressor motor inverter 4 to drive the compressor motor 3 and to the drive motor 11 via the drive motor inverter 12. The drive motor 11 is supplied to drive the drive motor 11.

Further, the fuel cell system is provided with a controller 14 which is connected to an external ignition switch (IGN) sensor 21, an accelerator sensor 22, and an instrument 23, and controls the above-mentioned components. The controller 14 outputs a control signal to each of the above-described units in accordance with a sensor signal from the ignition switch sensor 21 or the accelerator sensor 22, and presents the power generation state of the fuel cell system to the vehicle user using the instrument 23.

In this fuel cell system, the operating state of the DC / DC converter 7
A signal indicating the operation state of the drive motor inverter control unit 13 and the operation state of the compressor motor inverter control unit 5 is input.

[Structure of DC / DC Converter for High Power] FIG. 2 shows a DC / DC converter for high power included in the above-described fuel cell system.
2 shows a functional configuration of the DC converter 7. According to FIG. 2, the DC / DC converter 7 for high power is
4, a communication unit 31 for transmitting and receiving information to and from
AC voltage (electric energy) output from C / DC converter 7
Constant operation unit 32 for controlling communication, and communication delay operation unit 33
And an operation power value / operation power amount calculation unit 34, a load power value / load power amount calculation unit 35, and a power amount difference calculation unit 36.

The communication section 31 is connected to the controller 14. The communication unit 31 receives a command power value from the controller 14 and outputs the input command power value to the operation constant calculation unit 32.

The operation constant calculation unit 32 determines an operation constant when the power is supplied from the high-power DC / DC converter 7 to the secondary battery 8 or the drive motor inverter 12 according to the command power value from the communication unit 31.

The communication delay calculator 33 has a memory therein and stores therein an internal processing delay time constant Tsd and a communication delay time constant Ttd in advance. The communication delay calculating unit 33 determines, based on these constants Ttd and Tsd, the high-power DC / DC converter 7 when the command power value is input at time t1.
And the time t3 at which the supply of power to the drive motor inverter 12 and the compressor motor inverter 4 is started. The communication delay calculator 33 outputs the calculated time t3 to the operating power value / operating power amount calculator 34.

The operating power value / operating power amount calculator 34 calculates an operating power value output from the high-power DC / DC converter 7,
Calculate the operating power. The operation power value / operation power amount calculation unit 34 outputs the calculated operation power amount to the power amount difference calculation unit 36.

The load power value / load power amount calculation section 35 stores a load delay time constant Tsd1 therein, and after a command power value is input using the constant Tsd1, the compressor motor inverter 4 and the drive motor inverter 12
Is calculated, and a time t4 when the load power value reaches the command power value is calculated. Further, the load power value / load power amount calculation unit 35 calculates the load power value and the load power amount from the time t2 to the time t4, and outputs the calculated load power amount to the power amount difference calculation unit 36.

The power amount difference calculating unit 36 calculates the operating power value and the load power amount from the load power value / load power amount calculating unit 35.
An operation for subtracting the operation power amount from the operation power amount calculation unit 34 is performed to obtain a power amount difference. This difference in the amount of power is
From the compressor motor inverter 4 and the drive motor inverter 12. The power difference calculator 36 calculates the power difference calculated by the controller 1
4 is output.

[Power Control Processing of Fuel Cell System] FIG.
The following shows a processing procedure of the power control processing by the above-described fuel cell system.

According to FIG. 3, first, in step S1, the operation of the operation key by the vehicle driver causes the controller 14 to determine whether or not the ignition switch is turned on by a sensor signal from the ignition switch sensor 21. Determined by If the ignition switch is on, the process proceeds to step S2, and if the ignition switch is not on, the process ends.

In step S2, a command power value, which is an operation power command, is received by the communication unit 31 from the controller 14, and the process proceeds to step S3. The operation power command is, for example, a control signal indicating that power is supplied to the drive motor 11 from time t1 as shown in FIG.
It is generated by the controller 14 according to the operation amount of the accelerator based on the sensor signal from. Also, the controller 14
Outputs an operating power command to the DC / DC converter 7 for strong electricity, and outputs the drive motor inverter control unit 13, the compressor motor inverter control unit 5, and the hydrogen storage device 6
To output a control signal. Here, the controller 14
As the power to be taken out of the fuel cell stack 1, a command power value indicating the total value of the power consumed by the drive motor 11 and the power consumed by the compressor 2 is referred to as DC / DC for high power.
Output to converter 7.

In step S3, the operation constant calculator 32 determines whether or not the command power value received in step S2 is a positive value. When the command power value is a positive value, the process proceeds to step S4, and when the operation power command is not a positive value, the process returns to step S2. That is, in step S3, the processing after step S3 is started only when a command to drive the drive motor 11 is issued.

In step S4, the operation constant of the high-power DC / DC converter 7 for executing the operation power command received in step S2 is obtained by the operation constant calculation unit 32, and the operation constant from the fuel cell stack 1 is determined based on the determined operation constant. The generated power is taken out and supplied to the secondary battery 8 or the drive motor inverter 12, and the process proceeds to step S5. This operation constant is expressed, for example, by a duty ratio for operating the switching element when the power control when outputting from the high-power DC / DC converter 7 to the secondary battery 8 or the like is switched by the switching element.

In step S5, the communication delay calculator 33 calculates a time t3 at which the high-power DC / DC converter 7 starts operating with a delay. A communication delay time constant Ttd, which is stored in advance in a memory in the communication delay calculation unit 33 and indicates the delay of communication with the controller 14,
An internal processing delay time constant Tsd indicating the internal processing delay time in the C converter 7 is read. The above communication delay time constant T
td is determined by the system configuration of the entire fuel cell system, and the internal processing delay time constant Tsd is determined by the system configuration and software configuration of the entire fuel cell system. The communication delay calculator 33 calculates the read constants Ttd, Ttd
Based on the sd, a time t3 at which the high-voltage DC / DC converter 7 in FIG.
Processing proceeds to

In step S6, the compressor motor inverter controller 5 and the drive motor inverter controller 13
Is calculated by the load power value / load power amount calculation unit 35. At this time, the load power value / load power amount calculation unit 3
5 reads the load delay time constant Tsd1 stored in the internal memory in advance, and obtains the time t2 in FIG. 5 based on the load delay time constant Tsd1. Time t2 in FIG.
Is a time at which the controller 14 outputs a control signal from the controller 14 to the compressor motor inverter control unit 5 and the drive motor inverter control unit 13 at time t1, and the drive motor 11 is actually driven.

Here, the required time ΔT1 required for the operating power to reach the command power value is determined by a change in the command power value. The required time ΔT1 is calculated from a map or a calculation formula based on the change ΔP in the command power value. As an example of the calculation formula, the required time ΔT1 = ΔP / ΔPt1 is expressed. ΔPt1 is a power change amount per unit time, and is a constant stored in the memory in advance.

The load power value / load power amount calculation unit 35 determines the required time ΔT1 by using the above-mentioned calculation formula or map,
The required time ΔT1 and time t2 are added to obtain time t4 in FIG. As a result, the load power value / load power amount calculation unit 35 determines that the drive motor inverter 12 and the compressor motor inverter 4 start operating after the command power value is input to the communication unit 31 at time t1. , A time t4 at which the power is gradually supplied from and the power of the command power value is supplied to the drive motor 11 is obtained.

In the next step S7, DC / DC
The operating power value / operating power amount calculation unit 3 determines the delay of the converter 7.
4 is calculated. The required time ΔTd required for the power output from the high-power DC / DC converter 7 to reach the command power value is calculated from a map or a calculation formula based on the change ΔP of the command power value. An example of the calculation formula is represented by a required time ΔTd = ΔP / ΔPtd. ΔPtd is a power change amount per unit time, and is a constant stored in the memory in advance.

The operating power value / operating power amount calculating section 34 calculates the required time ΔTd using the above formula or map.
The required time ΔTd and the time t3 are added to obtain the time t5 in FIG. Accordingly, the operating power value / operating power amount calculating unit 34 determines that the high-power DC / DC converter 7 has been turned on at time t
The operation is started at 3, and a time t5 at which the power of the command power value is supplied is obtained.

Here, the operation constant calculating section 32 outputs the D
The load power value / load power amount calculation unit 3 is configured to prevent the drive motor 11 from operating earlier than the C / DC converter 7.
5 so that ΔTd calculated by the operating power value / operating power amount calculation unit 34 becomes larger than the required time ΔT1 calculated in (5).
1 ≦ ΔTd), and determine the operation constant.

In the next step S8, the load power value and the load power amount each time the time elapses from time t2 to time t4 obtained in step S6 are calculated.
5 and the process proceeds to step S9. At this time, the load power value / load power amount calculation unit 35 calculates the load power value ΔP1 per unit time using a calculation expression expressed by ΔP1 = ΔPt1 × elapsed time ΔPt1: power change amount per unit time, The load power amount ΔWh1 per unit time is calculated by a calculation expression represented by ΔWh1 = ΔP1 / 3600, and the load power amount Wh1 integrated from time t2 is calculated by a calculation expression expressed by Wh1 = Wh1 + ΔWh1.

In step S9, from time t3 to time t5
The operation power value and the operation power amount of the high-power DC / DC converter 7 are calculated by the operation power value / operation power amount calculation unit 34, and the process proceeds to step S10. At this time,
The operating power value / operating power amount calculation unit 34 calculates the operating power value ΔPd per unit time using a calculation expression expressed by ΔPd = ΔPtd × elapsed time ΔPtd: power change amount per unit time, Is calculated by a calculation expression expressed by ΔWhd = ΔPd / 3600, and the integrated operation power amount Whd from time t3 to time t4 is calculated by an operation expression expressed by Whd = Whd + ΔWhd.

In step S10, a power amount difference (Wh1-Whd) between the load power amount Wh1 obtained in step S8 and the operation power amount Whd obtained in step S9 is obtained by the power amount difference calculation unit 36, and the process proceeds to step S11. Proceed with the process.
The power difference calculator 36 obtains the power consumed by the secondary battery 8 by outputting the power difference to the drive motor inverter 12 by calculating the power difference.

In step S11, the controller 14 determines whether or not the ignition switch is on based on a sensor signal from the ignition switch sensor 21.
Determined by When the ignition switch is on, the process proceeds to step S12, and when the ignition switch is not on, the process ends.

In step S12, the command power value is received from the controller 14 by the communication unit 31, and in step S13
Processing proceeds to

In step S13, it is determined whether or not the command power value received in step S12 is in a steady state. That is, the communication unit 31 compares the command power value received in step S12 with the command power value received in step S2 or the previous command power value, and when the current command power value is substantially equal to the previous command power value, If it is determined that it is in the steady state, the process proceeds to step S15. If it is determined that the values are not substantially the same, it is determined that it is in the unsteady state, and the process proceeds to step S14.

In step S14, the communication section 31 determines whether or not the command power value received in step S12 is a positive value. If the command power value is a positive value, the process proceeds to step S5.
And the process from step S5 is performed again. If the value is not a positive value, the process returns to step S12, and the DC / DC converter 7 for strong current is operated with the operation constant determined at the current stage.
Is operated.

In step S15, the communication unit 31 determines whether or not the command power value received in step S12 is a positive value. If the command power value is a positive value, the process proceeds to step S1.
6, and if not positive, the process proceeds to step S12.
Return to

At step S16, the compressor motor inverter controller 5 and the drive motor inverter controller 13 respond to the point in time when the vehicle enters the steady state, that is, the command power value.
When the operation of the load is completed, the operation constant according to the command power value received in step S12 is calculated by the operation constant calculation unit 32 in order to change to the next command power value. The DC / DC converter 7 is operated, and the process returns to step S8.

At this time, the communication section 31 executes step S10
In the power amount difference ΔWh calculated by the power amount difference
Is transmitted to the controller 14, and the controller 14 sets the operation power value to which the latest power amount difference ΔWh received when the next command power value is output to the communication unit 31 is added. Thus, when the controller 14 outputs the next command power value to operate the high-power DC / DC converter 7, the controller 14 outputs the previous load power value and the high-power DC / DC converter 7.
Can be made equal to each other, and for example, the power consumed by the secondary battery 8 can be reduced.

Therefore, in the fuel cell system including the high-power DC / DC converter 7 performing such processing, the high-power DC / DC converter 7
And the next command power value from the controller 14 is added to the power DC / DC
Since the power is output to the converter 7, a large amount of power is supplied from the high-power DC / DC converter 7 to the drive motor inverter 12, and as shown in FIG. 7, the power amount difference ΔWh between the load power value and the operation power value is calculated. The amount of power to supplement the secondary battery 8 with the charging power can be reduced. That is, in this fuel cell system, the electric energy difference ΔWh is determined by the DC / D
By outputting a large amount from the C converter 7 to the secondary battery 8 or the drive motor inverter 12, it is possible to reduce the consumption of the charging power of the secondary battery 8 and to keep the charging level of the secondary battery 8 high. Therefore, according to this fuel cell system, the delay in power supply to the load can be reduced, and the charging power of the secondary battery 8 can be effectively used.

Further, according to this fuel cell system, it is possible to cope with a delay or a fluctuation with respect to the command power value by predicting the next change in load power from the previous power amount difference. Therefore, according to this fuel cell system, various internal constants are determined based on the calculated delay of power supply, as well as control for adjusting the power balance of the secondary battery 8 by the DC / DC converter 7 for high power. This can be applied to more cases.

The above embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and other than the present embodiment, various modifications may be made according to the design and the like within a range not departing from the technical idea according to the present invention. Can be changed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a fuel cell system to which the present invention is applied.

FIG. 2 is a block diagram showing a functional configuration of a high-power DC / DC converter to which the present invention is applied.

FIG. 3 is a flowchart illustrating a processing procedure of a high-power DC / DC converter.

FIG. 4 is a diagram showing a change in a command power value supplied from a controller to a communication unit.

FIG. 5 is a diagram showing a change in load power supplied to a drive motor inverter or a compressor motor inverter for driving a drive motor or the like serving as a load.

FIG. 6 is a diagram showing a change in operating power output from a high-power DC / DC converter.

FIG. 7 is a diagram illustrating power output from a secondary battery based on a change in a command power value, a change in load power, and a change in operating power.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel cell stack 2 Compressor 3 Compressor motor 4 Compressor motor inverter 5 Compressor motor inverter control part 6 Hydrogen storage device 7 DC / DC converter for strong electricity 8 Secondary battery 9 12V DC / DC converter 10 12V battery 12 Drive motor inverter 13 Drive Motor inverter control unit 14 Controller 31 Communication unit 32 Operation constant calculation unit 33 Communication delay calculation unit 34 Operation power value / operation power amount calculation unit 35 Load power value / load power amount calculation unit 36 Power amount calculation unit

Claims (4)

[Claims] An electric power control device for supplying electric power generated by a fuel cell to a load circuit and storing the electric power in a secondary battery, wherein the electric power generated from the fuel cell is input to the load circuit or the secondary battery. A generated power input / output unit for supplying power, a signal input unit to which a signal indicating a command power amount is input from outside, and a load power amount supplied to the load circuit from the secondary battery or the generated power input / output unit , An operating power calculating means for calculating the operating power output from the generated power input / output means, a load power calculated by the load power calculating means, and the operating power. A power amount difference calculating means for calculating a power amount difference from the operating power amount calculated by the power amount calculating means; and a power amount corresponding to the power amount difference calculated by the power amount difference calculating means, the next time, Power generation Control means for determining the amount of operating power output from the power input / output means and controlling the generated power input / output means so as to supply power to the load circuit or the secondary battery. Control device. 2. The control means according to claim 1, wherein the control means determines an operation power amount obtained by increasing the operation power amount by the power amount difference from the load power amount, and supplies the power to the load circuit or the secondary battery. 2. The power control device according to claim 1, wherein the power control unit controls the generated power input / output unit. 3. A method of controlling a power supply device for supplying power generated by a fuel cell to a load circuit and storing the power in a secondary battery, wherein a signal indicating a command power amount is input from the outside; Calculating the amount of load power supplied to the secondary battery or the load circuit from the step; calculating the amount of operating power output from the power control device; and the power of the load power and the operating power Calculating an amount difference, and determining an operation amount of power to be output from the power supply device next time based on the amount of power corresponding to the amount of power difference, and supplying power to the load circuit or the secondary battery. Controlling the power supply device. 4. The method according to claim 1, further comprising determining an operation power amount obtained by increasing the operation power amount by the power amount difference from the load power amount, and supplying power to the load circuit or the secondary battery. 3. The control method of the power supply device according to 3.