JP2002141091A - Control device of fuel cell power supply - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a fuel cell power supply which supplies power of a power supply with high efficiency using in a good conductive condition a fuel cell and a secondary cell avoiding an out-of-gas condition of a fuel cell. SOLUTION: A power source output controlling device 10 calculates a power generation indicating value of a fuel cell 11 based on a system request output and a remaining capacity of a secondary cell 12, and outputs the value to a fuel cell controlling device 17. The fuel cell controlling device 17 calculates an output possible value of the fuel cell to the power generation indicating value, than outputs this to the power source output controlling device 10. The power source output controlling device 10 calculates an output limiting value PLD of the power supply based on a system request output and the output possible value of the fuel cell 11, and also controls the calculated output limiting value not to be more than a limiting value to the secondary cell 12, then outputs the output limiting value PLD to a motor controlling device 15. The motor controlling device 15 controls a traction motor driving device 14, based on the output limiting value PLD.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control of a fuel cell power supply device in which a fuel cell and a secondary battery are arranged in parallel and the power supply of a fuel cell power supply device used in an electrically good state is controlled. Related to the device.

[0002]

2. Description of the Related Art Conventionally, as a power supply for a fuel cell vehicle, a hybrid power supply device combining a fuel cell and a secondary battery has been known. This hybrid type power supply unit compensates for the power generation shortage caused by the response delay of the fuel cell at the time of transient fluctuation of the running motor load by the energy stored in the secondary battery and stably supplies the required power. .

As described above, the response delay of the fuel cell occurs at the time of a transient change. Therefore, if an attempt is made to obtain an output corresponding to the load change immediately after the load change, the fuel supply amount becomes insufficient with respect to the output. It falls into a so-called gas-out state. Therefore, conventionally, an output controller including a DC / DC converter or the like for controlling the output of the fuel cell is provided between the fuel cell and the secondary battery, and the output of the fuel cell is supplied to the fuel cell by the output controller. It was controlled to an amount corresponding to the amount of reaction gas (air and fuel) to be used.

[0004]

However, the above-mentioned output controller controls the output by turning on / off a switching element provided therein at a high speed, so that the power loss accompanying the switching is large. was there. In addition, the output controller needs to have a large current capacity in order to correspond to the maximum current value that can be output by the fuel cell, and there has been a problem that the device becomes large-sized accordingly.

The present invention has been made in view of such circumstances, and a fuel cell and a secondary battery are arranged in parallel and used in a well-conducted state while avoiding a fuel cell out-of-gas state. It is an object of the present invention to provide a control device for a fuel cell power supply that supplies the power of the fuel cell power supply with high efficiency.

[0006]

In order to achieve the above object, the present invention provides a fuel cell (for example, a fuel cell 11 in an embodiment described later) and a secondary battery (for example, a fuel cell in an embodiment described later). Secondary battery 12, and the secondary battery 12
Is smaller than the output capacity of the fuel cell) and is arranged in parallel, and controls the supply power of the fuel cell power supply used in an electrically conductive state (direct connection state). (For example, a power supply output control device 10 in an embodiment to be described later), and an external load control unit (for example, a motor control device 15 in an embodiment to be described later) that controls power supplied to an external load. Required output (for example, the motor control device 15 in an embodiment described later)
) And information on the remaining capacity of the secondary battery (for example, the remaining capacity of the secondary battery in an embodiment described later). ), The power generation instruction value of the fuel cell is calculated (for example, it is derived based on the system required output-fuel cell output characteristic shown in FIG. 6 in an embodiment described later), and the power generation instruction value is calculated. Output to a fuel cell control means (for example, a fuel cell control device 17 in an embodiment to be described later) for controlling a supply amount of the reaction gas to the fuel cell, and an output possible value of the fuel cell (for example, In an embodiment described later, the fuel cell control unit 17 calculates the pressure and the flow rate of the reaction gas currently supplied to the fuel cell 11). And calculates an output possible value of the fuel cell power supply based on the output possible value of the fuel cell and the remaining capacity related information of the secondary battery (the output possible value of the fuel cell power supply is The combined output possible value of the battery and the secondary battery, for example, the combined curve A shown in FIG.
The required output, the smaller of the output possible value of the fuel cell and the output possible value of the fuel cell power supply, the remaining capacity related information of the secondary battery, and the secondary The output value of the external load control means (for example, a torque command output from a motor control device in an embodiment described later) is limited based on a limit value for a battery.

As described above, the control device of the fuel cell power supply device of the present invention controls the power supply of the fuel cell power supply device that uses the fuel cell and the secondary battery in an electrically good state. The required output, the smaller of the output possible value of the fuel cell and the output possible value of the fuel cell power supply device, the remaining capacity related information of the secondary battery, and the limit value for the secondary battery, Since the power supply to the motor is restricted, an output controller including a DC / DC converter or the like as in the related art can be eliminated, and the fuel cell can be prevented from being out of gas.

Further, the present invention is a control device for a fuel cell power supply device in which a fuel cell and a secondary battery are arranged in parallel and which controls the power supplied to the fuel cell power supply device used in an electrically good state. A power generation instruction value of the fuel cell is calculated based on a required output from external load control means for controlling power supplied to an external load and the remaining capacity related information of the secondary battery, and Output to the fuel cell control means for controlling the supply amount of the reaction gas, receiving the output possible value of the fuel cell with respect to the power generation instruction value from the fuel cell control means, and outputting the required output and the output possible value of the fuel cell. An output possible value of the fuel cell power supply device is calculated based on the remaining capacity related information of the secondary battery (for example, in an embodiment described later, as shown in FIG. Secondary battery output Is obtained by adding the ability to value),
And a control device for the fuel cell power supply device, wherein the output value of the external load control means is limited so that the calculated possible output value of the fuel cell power supply device is equal to or less than a limit value for the secondary battery. .

As described above, the control device for a fuel cell power supply according to the present invention has a fuel cell and a secondary battery which are arranged in parallel, and which controls the supply power of the fuel cell power supply which is used in an electrically good state. It calculates the output possible value of the power supply based on information such as the output possible value of the fuel cell and the remaining capacity of the secondary battery, and further outputs the output possible value of the fuel cell power supply to the secondary battery. It is determined so as to be equal to or less than the limit value, and the power supply to the traveling motor is limited based on the determined possible output value. By controlling the supply power of the fuel cell power supply device in this manner, it is possible to eliminate the output controller including a DC / DC converter and the like as in the related art, and to prevent the fuel cell from running out of gas. it can.

Further, in the control device for a fuel cell power supply device, the limit value for the secondary battery may be a limit value for a protection device for the secondary battery (for example, a shutoff device 36 in an embodiment described later). This makes it possible to control the power supply of the fuel cell and the secondary battery so as not to overload the secondary battery.

In the control device of the fuel cell power supply device, the limit value for the secondary battery is an allowable charge / discharge current and voltage for each remaining capacity of the secondary battery (for example, FIG. (The lowest voltage value set for each remaining capacity shown),
The secondary battery can be used within the allowable use range.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A control device for a fuel cell power supply according to one embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a power output control device 10 as a control device of a fuel cell power device according to an embodiment of the present invention.
FIG. 1 is a schematic configuration diagram of a fuel cell vehicle 1 including: The fuel cell power supply device controlled by the power supply output control device 10 according to the present embodiment is a hybrid power supply device including a fuel cell 11 and a secondary battery 12. Fuel cell 11
And a secondary battery 12 is a driving motor 13 which is an electric load.
And the traveling motor 13 is supplied with the combined power of the fuel cell 11 and the secondary battery 12 (output power of the power supply device). The driving force of the traveling motor 13 is transmitted to driving wheels via a transmission or a reduction gear (not shown). When the driving force is transmitted from the driving wheels to the traveling motor 13 when the fuel cell vehicle 1 decelerates, the traveling motor 13 functions as a generator to generate a so-called regenerative braking force, and the kinetic energy of the vehicle body is reduced. Is recovered as electrical energy.

The traveling motor 13 is, for example, a three-phase AC synchronous motor of a permanent magnet type using a permanent magnet as a magnetic field.
The drive is controlled by the phase AC power. The traveling motor drive device 14 includes a PWM inverter including a switching element such as an IGBT, and is output from the fuel cell 11 and the secondary battery 12 based on a torque command output from the motor control device 15. DC power is converted into three-phase AC power and supplied to the traveling motor 13.

The fuel cell 11 has a structure in which a solid polymer electrolyte membrane made of, for example, a solid polymer ion exchange membrane is sandwiched between an anode and a cathode from both sides.
The fuel cell system includes a stack formed by stacking a plurality of cells, and includes a hydrogen electrode to which hydrogen gas is supplied as a fuel and an air electrode to which air containing oxygen as an oxidant is supplied. And the hydrogen ions generated by the catalytic reaction at the anode,
Moving through the solid polymer electrolyte membrane to the cathode,
The cathode generates an electrochemical reaction with oxygen to generate power.

The fuel cell 11 includes the fuel cell 1
The fuel cell monitor 18 detects the cell voltage of each cell, the output voltage of the fuel cell, the output current, the temperature, and the like and outputs the detected fuel cell to the fuel cell control device 17, and supplies the reaction gas (fuel gas and air) to the fuel cell 11. The accessory / control device 19 is connected to each. This accessory / control device 19 has the configuration shown in FIG.

In FIG. 2, an air compressor 20 connected to the air electrode side of the fuel cell 11 supplies air as a signal pressure to a regulator 21 in addition to the air electrode of the fuel cell 11, for example. For this reason, a motor (not shown) for driving the air compressor 20 is provided with a rotation speed command value N.
Is input from the fuel cell control device 17. The motor drives the air compressor 20 based on the input rotation speed command value N, whereby the air compressor 20 pressurizes air taken in from outside via the filter 22 and supplies the air to the heat exchanger 23. The pressurized air is supplied to the heat exchanger 2
3 and the filter 24 removes dust.

The air supplied to the humidifier 25 is humidified and supplied to the fuel cell 11, and after the above-described electrochemical reaction, air provided for adjusting the pressure of the air supplied to the fuel cell 11 is provided. It passes through the pressure regulating valve 26 and is discharged.
On the other hand, a regulator (also referred to as a proportional pressure regulator) 21 provided on the fuel supply side supplies hydrogen supplied from the high-pressure hydrogen tank 27 to the fuel cell 11 based on the pressure (pilot signal) of the air supplied from the air supply side. Adjust pressure. In this way, the regulator 21 controls the balance between the pressure on the air supply side and the pressure on the fuel supply side of the fuel cell 11.

Since the pressure of the hydrogen supplied from the high-pressure hydrogen tank 27 is high, the pressure is temporarily reduced by the electric shutoff valve 28 and then adjusted by the regulator 21.
It is supplied to the humidifier 25 via the ejector 29. The hydrogen humidified by the humidifier 25 is supplied to the fuel electrode side of the fuel cell 11, and after electrochemical change, is output as a discharge gas to the demister 30. In the demister 30, the supplied exhaust gas is separated into gas and liquid, and the gaseous hydrogen is circulated to the hydrogen supply unit via the ejector 29 and reused. Further, a purge valve 31 for discharging water remaining inside the fuel cell and the demister is provided on the discharge side of the hydrogen gas. The above-described electric shut-off valve 28 also has a function of shutting off the supply of hydrogen gas from the high-pressure hydrogen tank 27.

The water pumps 40, 41 circulate the cooling water radiated and cooled by the radiators 32, 33 into the fuel cell 11 and the accessory / control device 19, thus circulating the cooling water. Let the fuel cell 11
And controlling the temperature of the accessory / control device 19 to a predetermined temperature or lower. Here, the water pump 40 is connected to the fuel cell 1
The water pump 41 is provided for cooling each part of the air supply side, and for cooling each part of the auxiliary equipment / control device 19 and the fuel supply side.

In the above-described accessory / control device 19,
A drive signal is output to the air compressor 20 and the air pressure regulating valve 26 provided in the flow path on the air electrode exhaust side, and by controlling the drive amount and the open / close state, the reaction gas supply amount is controlled to control the fuel cell 11. The power generation is adjusted.

Returning to FIG. 1, a current sensor 34 provided in the output supply path of the fuel cell 11 detects a current flowing through the fuel cell at predetermined intervals, and outputs the detected current to the power output control device 10. Further, a cutoff device 35 for limiting a current flowing through the fuel cell 11 is provided in an output supply path of the fuel cell 11.

The secondary battery 12 constituting the power supply device of the present invention together with the fuel cell 11 has a very small output capacity with respect to the maximum required output (for example, about 1/3).
Is used. This is because the secondary battery 12 in the present embodiment is used as an auxiliary power supply to assist the output of the fuel cell 11 when the output of the fuel cell 11 is insufficient for the required output, for example, at the time of transient fluctuation of the required output. This is because it is provided. Further, a shutoff device 36 for limiting the current flowing through the secondary battery 12 to within a predetermined value is provided in the output supply path of the secondary battery 12. Further, the current sensor 37 detects a current flowing through the secondary battery every predetermined period and outputs the detected current to the power output control device 10.

The electric power from the power supply unit composed of the fuel cell 11 and the secondary battery 12 is also supplied to an electric load 38 other than the traveling motor mounted on the vehicle. Examples of the electric load 38 other than the traveling motor include a fan of an air conditioner, a cooling fan for cooling the secondary battery 12, and the like. In addition, a current sensor 39 is provided which detects a current flowing through an electric load other than the traveling motor at predetermined intervals and outputs the detected current to the power output control device 10.

[0024] The motor control unit 15 operates the accelerator pedal and the required torque Ap corresponding to the motor rotation speed Nm at that time.
Is input, the required output Pcmd is calculated from the required torque Ap and the motor rotational speed Nm, and the motor and switching efficiency η. This required output is given by the following equation (1). Pcmd = Ap × Nm × η (1) In practice, since the motor and the switching efficiency η change for each required torque and motor rotation speed, the motor and the switching efficiency η are determined by using the torque and the rotation speed as variables. It is better to provide the set three-dimensional lookup table in a storage device (not shown) of the control device in advance, and to obtain the motor and the switching efficiency η by referring to the three-dimensional lookup table. Further, the required motor output itself can be a three-dimensional lookup table based on the torque and the rotation speed. As described above, when calculating the required output Pcmd, the motor control device 15 outputs this value to the power output control device 10, receives an output limit value for the required output from the power output control device 10, and Driving motor drive device 1 based on
4 to control the power conversion operation of the PWM inverter.

The power supply output control device 10 determines the required output of the current vehicle system as a whole based on the required output input at predetermined intervals from the motor control device 15 and the required output from the electric load 38 other than the traveling motor. Aggregate (hereafter,
Then, the output supply of the fuel cell 11 to the system required output is calculated, and this value is output to the fuel cell control device 17 as a power generation instruction value. Further, when the power supply output control device 10 receives from the fuel cell control device 17 the possible output value of the fuel cell 11 with respect to the power generation instruction value, the possible output value or the possible output value of the fuel cell power supply, the required output, and the An output limit value is calculated based on the remaining capacity, a limit value for the secondary battery, and the like, and is output to the motor output device 15. The details of the output limit value calculation process performed by the power output control device 10 will be described later.

The fuel cell controller 17 controls the fuel cell 1 based on the power generation instruction value input from the power output controller 10.
In order to control the amount of reactant gas supplied to the fuel cell 1, a rotational speed command value as a drive command for an auxiliary device for driving a fuel cell, specifically, a motor for driving the air compressor 20 shown in FIG. N, the current value that can be output from the fuel cell 11 at present is calculated from the pressure and flow rate of the reactant gas input from the accessory / control device 19, and this value is used as an outputable value as the output value. Output to

The above-mentioned motor control device 15, power supply output control device 10, and fuel cell control device 17 are all configured as logic circuits centered on a microcomputer, and include a CPU, a ROM (read only memory), and a RAM (read only memory). r
andom access memory) and input / output ports.
The CPU executes a predetermined operation according to a preset control program. The ROM stores in advance control programs and control data necessary for the CPU to execute various arithmetic processing, and the RAM also stores the CPU.
, Various data necessary for executing various arithmetic processing are read and written temporarily. The input / output port functions as an interface for transmitting and receiving signals to and from each unit.

Next, the processing performed by the power output control device 10 according to the present embodiment in the fuel cell vehicle 1 having the above configuration will be described in detail. Note that the following processing is performed by each control device repeatedly executing a control program every predetermined period.

First, when the required torque Ap, which is a signal corresponding to the operation of the accelerator pedal, is input to the motor control device 15, the required torque Ap and the traveling motor drive device 1 are input.
The required output is calculated based on the DC current component signal Im of the traveling motor 13 and the rotation speed Nm of the traveling motor which are input from 4 and output to the power output control device 10.

In addition to the required output input from the motor control device 15, a required output signal is also input to the power output control device 10 from an electric load 38 other than the traveling motor. The power output control device 10 adds these required outputs to calculate a system required output that is currently required for the entire vehicle system. In addition, predetermined information of the secondary battery 12, for example, information on the battery voltage, battery current, and battery temperature between the secondary batteries 12 is input to the power output control device 10. The remaining capacity of the secondary battery 12 is calculated (detected) from this information. After calculating the system required output as described above, the power supply output control device 10 then determines the fuel cell 11 for the system required output based on the remaining capacity of the secondary battery 12, the battery temperature, the battery voltage, and the battery current. The output distribution with the secondary battery 12 is determined.

First, FIG. 3 shows a fuel cell 1 according to this embodiment.
1 shows an output characteristic (current-voltage characteristic) and an output characteristic of the secondary battery 12. In the figure, line A represents the output characteristics of the fuel cell, and lines B1 to B5 represent the output characteristics of the secondary battery 12 at each remaining capacity (SOC) of the secondary battery 12. As described above, the output characteristics of the fuel cell 11 are shown by one curve, whereas the output characteristics of the secondary battery 12 vary depending on the remaining capacity. The higher the remaining capacity, the higher the output voltage for a predetermined current.

FIG. 4 shows the output characteristics of the secondary battery 12 when the remaining capacity of the secondary battery 12 is 80% (line B4 in the same figure) and the combined output of the secondary battery 12 and the fuel cell 12 under the same conditions. The output characteristic of the power supply device, which is the characteristic (line C in the figure), and the output characteristic of the fuel cell 11 (line A in the figure) are shown. Furthermore,
FIG. 5 shows power-voltage characteristics of the power supply device when the remaining capacity of the secondary battery 12 is 80%.

Now, for example, if the system required output is power P1
Considering the case where
Then, the output current If1 of the fuel cell 11 and the output current Ib1 of the secondary battery 12 corresponding to the voltage V1 are derived with reference to FIG. Similarly, the output current of the power supply device changes from line C to I1, and this I1 can also be obtained by adding the output current If1 of the fuel cell 11 and the output current Ib1 of the secondary battery 12. As described above, in order for the power supply device according to the present embodiment to supply the power P1, the secondary battery 12
It can be seen that the fuel cell 11 should output If1.

Then, the output distribution characteristic of the fuel cell 11 is obtained for each remaining capacity of the secondary battery 12 by the above-described method, so that the fuel output corresponding to the required output (electric power) at each remaining capacity of the secondary battery 12 is obtained. Characteristics indicating the output (power) of the battery 11 are required. FIG. 6 shows that the remaining capacity of the secondary battery 12 is 3
FIG. 9 illustrates the system required output-fuel cell output characteristics at 0%, 50%, and 80%. The power output control device 10 detects the output of the fuel cell 11 with respect to the system required output based on the characteristics shown in FIG.

For example, if the system required output is P1 and the remaining capacity of the secondary battery 12 is 50%, the power supply output control device 10 refers to FIG.
Is detected, and this output is output to the fuel cell controller 10 as the power generation command amount of the fuel cell 11. As described above, the power output control device 1
Numeral 0 has the system required output-fuel cell output characteristic shown in FIG. 6, and the power generation instruction amount of the fuel cell 11 is detected based on this characteristic.

In this embodiment, the case where the power value is input as the system required output and the power generation instruction value of the fuel cell 11 corresponding to the power value is detected as described above has been described as an example. From the current-voltage characteristics shown in FIG. 4 and the power-voltage characteristics shown in FIG. 5, conversion from current to voltage and conversion from voltage to power can be arbitrarily performed. Is input, the power output control device 10 can determine the output distribution of the fuel cell 11.

The fuel cell control device 17 controls the amount of reaction gas based on the power generation instruction value input from the power output control device 10. Specifically, the fuel cell 11 shown in FIG.
The rotation speed command value N to the motor that drives the air compressor 20, which is an auxiliary device, is increased or decreased based on the power generation command value. Further, the fuel cell control device 17 includes the accessory / control device 1
From 9, a current value that can be output from the fuel cell 11 at present is obtained from the pressure and flow rate of the reaction gas currently supplied to the fuel cell 11, and this current value is output to the power output control device 10 as an outputable value.

When the power supply output control device 10 receives the output possible value as the current value from the fuel cell control device 10, it calculates the output limit value and outputs this value to the motor control device 15. Hereinafter, the calculation processing of the output limit value will be described in detail with reference to FIG.

FIG. 7 is a diagram showing the processing performed by the power supply output control device 10 as functional blocks. In the figure, a series of processes from assigning a reference numeral to each functional block and deriving an output limit value will be described. First, block 100
In the above, the output possible value which is the current value received from the fuel cell control device 17 is calculated based on the output possible value of the fuel cell 11 and the remaining capacity related information of the secondary battery 12. And a combined output with the secondary battery) in order to be able to compare with the possible output value. This can be derived by referring to the characteristics shown in FIGS. Next, in block 101, the output possible value of the fuel cell 11 converted into electric power is compared with the output available value of the fuel cell power supply device, and a smaller value is selected.

In the following block 102, the previous block 1
In step 01, the system request output is subtracted from any of the possible output values selected to obtain a difference. Meanwhile, block 1
At 03, the possible output value of the secondary battery 12 is calculated. This possible output value is calculated based on the temperature and the remaining capacity of the secondary battery 12. Specifically, the temperature-output power characteristics of the secondary battery 12 shown in FIGS.
Using the remaining capacity-output power characteristic of the secondary battery shown in (a) and (b), an output possible value based on temperature and an output possible value based on remaining capacity are detected. 8 (a) and 9 (a) show the characteristics at the time of discharging (when the driving motor is driven), and FIGS. 8 (b) and 9 (b) show the characteristics at the time of charging (when driving). This shows the characteristics at the time of motor regeneration). The power output control device 10 switches the characteristics to be referred according to the charge / discharge state of the secondary battery 12. When the output possible value based on the temperature of the secondary battery 12 and the output possible value based on the remaining capacity are detected by performing the above-described processing, the smaller of the detected two values can be output from the current secondary battery 12. Determine as a value.

When the possible output value of the secondary battery 12 is derived by the above-described method, in block 104, the value calculated in the previous block 102 is replaced with the value in block 103.
The possible output value of the secondary battery 12 calculated in is added.

Subsequently, in block 105, the voltage limit value of the secondary battery 12 is calculated, and in block 106, the limit value of the shutoff device is calculated. Here, the secondary battery 1
The limit value of the second shutoff device 36 is, for example, a set value of a fuse provided to limit the current flowing through the secondary battery 12. This is a limit value provided to prevent deterioration of the secondary battery 12 due to overcurrent. Further, it is said that the secondary battery 12 is preferably used in a range of 20% to 80% of the remaining amount. This is because in a region where the remaining capacity is 20% or less, there is a high possibility that the battery will be in an overdischarged state and reverse charging will occur. This causes the charging efficiency to decrease, and also causes the secondary battery to deteriorate in performance due to heat. Further, a minimum allowable voltage is set for each remaining capacity. This is because the secondary battery is used in a more preferable voltage range. This minimum allowable voltage value is set, for example, to a value as shown in FIG.

Accordingly, the power supply output control device 10 sets the limit value of the shutoff device 36 and the voltage limit value for each remaining capacity,
At block 108, the value selected at block 107 is subtracted from the value calculated at block 104 so that the secondary battery operates within these limits. This can prevent the above-described overcurrent and prevent the use of the secondary battery 12 in an undesirable area.

In the following block 109, block 107
Further, a limit is added to the output limit value obtained in. In this block 109, for example, it is determined whether or not the output limit value is within the range of 0 kW to 75 kW. If the output limit value is within the range, the output limit value is output as it is. Is within the specified range, the output limit value is changed to a value within the range. When obtaining the output limit value by the above-described series of processing, the power output control device 10 outputs the output limit value to the motor control device 15.

The motor control device 15 controls the PW provided in the traveling motor drive device 14 based on the output limit value input from the power output control device 10 and the system required output.
Limit the power conversion operation of the M inverter. In particular,
As a torque command, for example, a U-phase AC voltage command value, a V-phase AC voltage command value, and a W-phase AC voltage command value are output to the traveling motor drive device 14, and the U-phase current and V corresponding to each of these voltage command values are output. The phase current and the W-phase current are output from the traveling motor drive device 14 to each phase of the traveling motor 11.

As described above, referring to FIG.
Has been described, the output limit value can also be calculated by the method shown in FIG. Hereinafter, an output limit value calculation process according to another embodiment will be described with reference to FIG.

In FIG. 10, first, in block 200, the output possible value, which is the current value received from the fuel cell control device 17, is based on the output possible value of the fuel cell 11 and the remaining capacity related information of the secondary battery 12. Is converted to an electric power value so that it can be compared with the output possible value of the fuel cell power supply device (combined output of the fuel cell and the secondary battery) calculated in step 201, and the output of the fuel cell 11 converted to electric power in the subsequent block 201 is possible. The value is compared with the output possible value of the fuel cell power supply device, and a smaller value is selected. These processes are the same as the processes in blocks 100 and 101 in FIG.

On the other hand, in block 202, the secondary battery 12
The output possible value according to the temperature of is calculated.
At 03, an outputable value based on the remaining capacity of the secondary battery 12 is calculated. Specifically, the power output control device 10
The temperature-output power characteristics of the secondary battery 12 shown in FIGS. 9A and 9B and the remaining capacity of the secondary battery 12 shown in FIGS. 9A and 9B.
The output possible value based on the temperature and the output possible value based on the remaining capacity are detected using the output power characteristics. Note that FIG.
(A) and FIG. 9 (a) are at the time of discharge (at the time of driving the driving motor)
8 (b) and FIG.
(B) shows the characteristics at the time of charging (during regeneration of the motor for traveling). The power output control device 10 switches the characteristics to be referred according to the charge / discharge state of the secondary battery 12.

By performing the above-described processing, the secondary battery 1
When the output possible value based on the temperature and the output possible value based on the remaining capacity are detected, the smaller of the two detected values is determined as the current output possible value of the secondary battery 12 in block 204.

Then, in block 205, one of the output possible values selected in the previous block 201 and the output possible value of the secondary battery 12 determined in block 204 are added, and the output possible value as the fuel cell power supply device is obtained. Calculate the value. Subsequently, in block 206, the output possible value of the fuel cell power supply device calculated in the previous block 205 is compared with the system required output, and if the output possible value of the fuel cell power supply is larger than the system required output, The system required output is set as the output limit value. On the other hand, when the output possible value of the fuel cell power supply is smaller than the required output, the output possible value of the fuel cell power supply is set as the output limit value.

When the output limit value is calculated in the block 206 as described above, in the subsequent block 207, the output limit value determined in the previous block 206 is calculated by the protection device for the secondary battery 12 obtained in the block 207, That is, it is determined whether or not the limit value of the cutoff device 36 and the allowable charge / discharge current and voltage for each remaining capacity of the secondary battery determined in the block 208 are equal to or less than the limit value. Then, the limit value is changed so that the output limit value is within the limit value.

The limit value of the shut-off device 36 of the secondary battery 12 obtained in the block 207 is, for example, the value of the fuse provided for limiting the current flowing through the secondary battery 12 in the same manner as described with reference to FIG. Set value. This is a limit value provided to prevent deterioration of the secondary battery 12 due to overcurrent. Further, the control values of the charge / discharge current and voltage of the secondary battery obtained in block 208 are limit values set for using the secondary battery in a more preferable voltage range, and have the values shown in FIG. Is set. Generally, the rechargeable battery 12 has a remaining capacity of 20% to 80%.
It is said that it is preferable to use in the range. This is because in a region where the remaining capacity is 20% or less, there is a high possibility that the battery will be in an overdischarged state and reverse charging will occur.
On the other hand, in a region where the remaining capacity is 80% or more, overcharging occurs and heat is generated, so that charging efficiency is reduced and heat also causes performance degradation of the secondary battery.

Therefore, the power supply output control device 10 charges the limit value of the shut-off device 36 and each remaining capacity in order to prevent the overcurrent as described above and to prevent the use of the secondary battery 12 in an undesirable area. Limit values are set for the discharge current and the voltage, and when the output limit value exceeds the limit value, the output current is limited to the limit value or less. When the power output control device 10 limits the output limit value to be within the limit value, the power output control device 10 outputs the output limit value to the motor control device 15.

The motor control device 15 controls the power conversion operation of the PWM inverter provided in the driving motor drive device 14 based on the output limit value input from the power output control device 10.

The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes a design and the like within the scope of the present invention. It is. For example, in the above-described embodiment, the motor control device, the power output control device, and the fuel cell control device are provided, respectively. However, the processing performed by these control devices can be realized by one control device.

[0056]

As described above, according to the control device for a fuel cell power supply of the present invention, the fuel cell and the secondary battery are connected in parallel, and the fuel cell is used in an electrically good state. It controls the power supply of the power supply device. The required output, the smaller of the possible output value of the fuel cell and the possible output value of the fuel cell power supply device, the remaining battery related information of the secondary battery, and Since the power supply to the traction motor is limited based on the limit value for the next battery, the DC /
An output controller including a DC converter and the like can be eliminated, and the fuel cell can be prevented from being out of gas. As a result, there is an effect that the power of the power supply device can be supplied to the traveling motor with high efficiency.

According to the control device of the fuel cell power supply device of the present invention, the output possible value of the fuel cell power supply device is calculated based on information such as the output possible value of the fuel cell and the remaining capacity of the secondary battery. Further, the output possible value of the fuel cell power supply device is limited so as to be equal to or less than the limit value for the secondary battery, and power is supplied to the traveling motor in the range of the output possible value. By controlling the power supply of the fuel cell power supply in this way, it is possible to prevent the fuel cell from running out of gas without using an output controller including a DC / DC converter or the like as in the related art. Thus, there is an effect that the power of the fuel cell power supply device can be supplied to the traveling motor with high efficiency.

Further, the control device of the fuel cell power supply device of the present invention limits the outputtable value so as to be equal to or less than the limit value of the protection device for the secondary battery. Thereby, the power supplied to the fuel cell and the secondary battery can be controlled so that the secondary battery is not overloaded, and the effect that the secondary battery can be downsized and the service life can be extended can be obtained. .

Further, the control device of the fuel cell power supply device of the present invention determines the output possible value of the fuel cell power supply device so as to be equal to or less than the limit value based on the allowable charge / discharge current and voltage for each remaining capacity of the secondary battery. Therefore, the secondary battery can be used within a preferable remaining capacity range. In addition, by performing the control according to the range of the remaining capacity in this manner, there is an effect that the size of the secondary battery can be reduced and the life of the secondary battery can be extended.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a system configuration of a fuel cell vehicle according to one embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of an accessory / control device according to the first embodiment.

FIG. 3 is a diagram illustrating an example of current-voltage characteristics of a fuel cell and a secondary battery.

FIG. 4 is a diagram illustrating current-voltage characteristics of a fuel cell, a secondary battery, and a power supply device when the remaining capacity of the secondary battery is 80%.

FIG. 5 is a diagram illustrating power-voltage characteristics of a power supply device in which a fuel cell and a secondary battery are connected in parallel when the remaining capacity of the secondary battery is 80%.

FIG. 6 is a diagram showing output power of a fuel cell with respect to a system required output.

FIG. 7 is a block diagram functionally showing a process performed by the power output control device in the embodiment.

FIG. 8 shows the temperature of the secondary battery during discharging and charging.
FIG. 4 is a diagram illustrating output power characteristics.

FIG. 9 is a diagram showing a remaining capacity-output power characteristic at the time of discharging and charging of the secondary battery.

FIG. 10 is a block diagram functionally showing a process performed by a power output control device according to another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fuel cell vehicle, 10 ... Power supply output control device (control device of power supply device), 11 ... Fuel cell, 12 ... Secondary battery, 13
... Motor for traveling, 14 ... Motor driving device for traveling, 15 ...
Motor control device, 35, 36 ... shut-off device, 17 ... fuel cell control device, 19 ... auxiliary equipment / control device, 20 ... air compressor, 21 ... regulator, 27 ... high-pressure hydrogen tank,
34, 37, 39: current sensor, 38: electric load other than the running motor, 40, 41: water pump

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shinji Yoshikawa 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. (Reference) 5H027 AA06 BA13 DD03 KK51 KK56 MM02 MM26

Claims (4)

[Claims] 1. A control device for a fuel cell power supply device in which a fuel cell and a secondary battery are arranged in parallel, and control the supply power of a fuel cell power supply device used in an electrically good state. A power generation instruction value of the fuel cell is calculated based on a required output from an external load control means for controlling power supplied to a load and information on a remaining capacity of the secondary battery, and the power generation instruction value is calculated by the fuel cell. Output to the fuel cell control means for controlling the supply amount of the reaction gas to the fuel cell; receiving an output possible value of the fuel cell with respect to the power generation instruction value from the fuel cell control means; An output possible value of the fuel cell power supply is calculated based on the remaining capacity related information of the battery, and any one of the required output, the output possible value of the fuel cell, and the output possible value of the fuel cell power supply is calculated. The smaller one,
A control device for a fuel cell power supply device, wherein an output value of the external load control means is limited based on remaining capacity related information of the secondary battery and a limit value for the secondary battery. 2. A control device for a fuel cell power supply device, wherein a fuel cell and a secondary battery are arranged in parallel, and control the supply power of a fuel cell power supply device used in an electrically good state. A power generation instruction value of the fuel cell is calculated based on a required output from an external load control means for controlling power supplied to a load and information on a remaining capacity of the secondary battery, and the power generation instruction value is calculated by the fuel cell. To the fuel cell control means for controlling the supply amount of the reaction gas to the fuel cell; receiving the output possible value of the fuel cell with respect to the power generation instruction value from the fuel cell control means; and outputting the required output and the output possible value of the fuel cell. Calculating the output possible value of the fuel cell power supply device based on the remaining capacity related information of the secondary battery, and the calculated output possible value of the fuel cell power supply device being equal to or less than the limit value for the secondary battery. Before A control device for a fuel cell power supply device, wherein an output value of said external load control means is limited. 3. The control device according to claim 1, wherein the limit value for the secondary battery is a limit value of a protection device for the secondary battery. 4. The fuel cell power supply device according to claim 1, wherein the limit value for the secondary battery is an allowable charge / discharge current and voltage for each remaining capacity of the secondary battery. Control device.