JP2018073565A - Warming method of fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a warming method of fuel cell system which allows for efficient execution of warming and power utilization.SOLUTION: A warming method of fuel cell system for warming fuel cells by low efficiency operation with generation efficiency lower than that of normal operation acquires a chargeable power value, i.e., the value of chargeable power in secondary battery, calculates a charge discharge loss value, i.e., the value of loss when charging and discharging the secondary battery with power of the chargeable power value, calculates a heat loss value, i.e., the value of heat loss when generating a power of the same amount as the chargeable power value by the fuel cell during normal operation, and when the heat loss value is larger than the charge discharge loss value, performs the low efficiency operation involving the charging of the secondary battery so that a power value, obtained by adding the chargeable power value to the generation power value when performing the low efficiency operation without involving the charging of the secondary battery, becomes the generation power value.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a method for warming up a fuel cell system.

  In order to realize the desired performance of the fuel cell in a low temperature environment, there is a technique for performing a warm-up operation of the fuel cell. For example, Patent Document 1 discloses a rapid warm-up method of a fuel cell in a low temperature environment below freezing point. In this method, the amount of heat generated is increased by performing a warm-up operation in which the reactant supplied to the fuel cell is in a shortage state and the power generation efficiency of the fuel cell is reduced.

Special table 2003-504807 gazette

  In general, in a vehicle equipped with a fuel cell, during rapid warm-up, only the power for driving the motor and accessories is generated by the fuel cell, and the amount of power for charging the secondary battery is There is no power generation. Therefore, the secondary battery cannot be charged during rapid warm-up. That is, the electric power generated during rapid warm-up cannot be reused by charging. Further, in view of loss due to charging / discharging of the secondary battery, charging of the secondary battery may cause deterioration of efficiency.

  The present invention has been made against the background described above, and an object of the present invention is to provide a fuel cell system warm-up method capable of efficiently performing warm-up and using power.

One aspect of the present invention for achieving the above object is a method for warming up a fuel cell system in which the fuel cell is warmed up by low-efficiency operation with lower power generation efficiency than normal operation, and can be charged in a secondary battery A chargeable power value that is a power value is acquired, a charge / discharge loss value that is a loss value when charging and discharging the power of the chargeable power value with respect to the secondary battery is calculated, and during the normal operation Calculate a heat loss value that is a heat loss value when the fuel cell generates the same amount of power as the chargeable power value, and if the heat loss value is larger than the charge / discharge loss value, The charging with the secondary battery is performed such that the power value obtained by adding the chargeable power value to the generated power value when performing the low-efficiency operation without charging the secondary battery becomes the generated power value. Warm up the fuel cell system for low-efficiency operation It is a method.
In such a method, when the heat loss during normal operation is larger than the charge / discharge loss, the secondary battery is charged during low-efficiency operation. For this reason, according to the above method, when the secondary battery is charged during normal operation, the energy lost due to heat loss is effectively utilized as the amount of heat at the time of rapid warm-up, and to the secondary battery during rapid warm-up. Can be charged. That is, in the above method, it is possible to efficiently perform warm-up and use power.

  ADVANTAGE OF THE INVENTION According to this invention, the warming-up method of the fuel cell system which can perform warming-up and electric power utilization efficiently can be provided.

It is a block diagram which shows an example of a structure of the fuel cell system concerning embodiment. It is a block diagram which shows an example of a function structure of a control part. It is a graph which shows an example of the time transition of the chargeable electric power value in the case of charging to a secondary battery at the time of rapid warm-up, and its correction value. It is a graph which shows the breakdown of the electric power of the fuel cell at the time of rapid warming-up. It is a flowchart which shows the operation example of the fuel cell system concerning embodiment. It is a graph explaining the correction | amendment by the chargeable electric power correction | amendment part. It is a schematic diagram which compares the case where it does not perform with the case where it charges to a secondary battery at the time of rapid warm-up.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating an example of a configuration of a fuel cell system 1 according to an embodiment. As shown in FIG. 1, the fuel cell system 1 according to the present embodiment includes a fuel cell 10, a temperature sensor 15, a secondary battery 20, a temperature sensor 25, a power distribution unit 30, a motor 40, Auxiliary machinery 50 and a control unit 60 are included. As will be described later, the fuel cell system 1 warms up the fuel cell by low-efficiency operation with lower power generation efficiency than normal operation. In the present embodiment, the fuel cell system 1 includes the motor 40 as an example of the load. However, the fuel cell system 1 may include other loads instead of the motor 40. The motor 40 is, for example, a motor that drives a wheel (not shown) of a vehicle on which the fuel cell system 1 is mounted.

  The fuel cell 10 generates power by a reaction between supplied fuel gas (for example, a gas containing hydrogen) and oxidizing gas (for example, air). The power generated by the fuel cell 10 is supplied to the motor 40, the auxiliary machinery 50, or the secondary battery 20 via the power distribution unit 30. The fuel cell 10 is provided with a temperature sensor 15 that measures the temperature of the fuel cell 10. The temperature sensor 15 outputs the measurement result to the control unit 60.

  The secondary battery 20 stores the power generated by the fuel cell 10. The internal resistance characteristics of the secondary battery 20 are specified in advance. For this reason, the charge / discharge loss when charging / discharging a certain electric power can be calculated using this internal resistance characteristic. The electric power stored in the secondary battery 20 is supplied to the auxiliary machinery 50 or the motor 40 via the power distribution unit 30. Note that the secondary battery 20 may store electric power generated by regenerative braking of the motor 40. The secondary battery 20 is provided with a temperature sensor 25 that measures the temperature of the secondary battery 20. The temperature sensor 25 outputs the measurement result to the control unit 60.

  The power distribution unit 30 distributes the input power according to the control signal of the control unit 60. Specifically, the power distribution unit 30 distributes the electric power generated by the fuel cell 10 to, for example, the motor 40, the auxiliary machinery 50, or the secondary battery 20. In addition, the power distribution unit 30 distributes the power output from the secondary battery 20 to the motor 40 or the auxiliary machinery 50, for example. The power distribution unit 30 may distribute the power output from the motor 40 to the secondary battery 20. The power distribution unit 30 is configured by an electric circuit such as a voltage converter, for example, in order to realize distribution. As described above, the fuel cell system 1 can arbitrarily adjust the outputs of the fuel cell 10 and the secondary battery 20 with respect to the required power from the load.

  The auxiliary machines 50 are various devices used for power generation of the fuel cell 10 such as a pump for supplying gas or the like to the fuel cell 10. In addition, the auxiliary machinery 50 may include devices for other purposes. The auxiliary machinery 50 is driven by electric power from the fuel cell 10 or the secondary battery 20.

  The control unit 60 is configured as a microcomputer including a CPU, a memory, and the like, and controls the operation of the fuel cell system 1. In particular, the control unit 60 performs control to switch between normal operation and low efficiency operation as the operation state of the fuel cell 10. For example, the control unit 60 controls the auxiliary equipment 50, the power distribution unit 30, and the like to switch the operation state. Here, in the low-efficiency operation, although the power generation efficiency is lower than that in the normal operation, the amount of heat during power generation can be increased as compared with the normal operation. More specifically, in the low-efficiency operation, the operating point of the fuel cell 10 is set to be lower than the operating point based on the current-voltage characteristics (hereinafter referred to as IV characteristics) of the fuel cell 10. This is an operating state with increased heat loss. In the fuel cell system 1, the fuel cell 10 is rapidly warmed up by performing the low-efficiency operation of the fuel cell 10 as described above.

  In addition, when the controller 60 performs rapid warm-up by low-efficiency operation of the fuel cell 10, when a predetermined condition is satisfied, the control unit 60 supplies the secondary battery 20 to the required power required by the motor 40 and the auxiliary devices 50. The total electric power obtained by adding the charging power for charging is controlled so that the fuel cell 10 generates power. This will be described together with an example of a functional configuration of the control unit 60. FIG. 2 is a block diagram illustrating an example of a functional configuration of the control unit 60. 2 is realized, for example, by executing a program by the CPU of the control unit 60.

  As shown in FIG. 2, the control unit 60 includes a temperature acquisition unit 61, an operation control unit 62, a chargeable power acquisition unit 63, a chargeable power correction unit 64, a charge / discharge loss calculation unit 65, a heat A loss calculation unit 66 and a charge determination unit 67 are included.

  The temperature acquisition unit 61 acquires measurement results from the temperature sensor 15 and the temperature sensor 25.

  The operation control unit 62 controls the operation state of the fuel cell 10. In particular, when the temperature of the fuel cell 10 acquired by the temperature acquisition unit 61 is equal to or lower than a predetermined temperature, the operation control unit 62 determines that the operation is performed in a low temperature environment, and performs rapid warm-up by low efficiency operation. To do. In addition, the operation control unit 62 determines the generated power value of the fuel cell 10 when the low-efficiency operation is performed based on the determination result of the charge determination unit 67 described later. Specifically, when the charging to the secondary battery 20 is permitted by the charge determination unit 67, the operation control unit 62 adds the power value corrected by the chargeable power correction unit 64 to the required power value. The value is set as the generated power value of the fuel cell 10. On the other hand, the operation control unit 62 sets the required power value as the generated power value of the fuel cell 10 when charging to the secondary battery 20 is prohibited by the charge determination unit 67.

  The chargeable power acquisition unit 63 acquires the current chargeable power of the secondary battery 20. Here, the chargeable power is a value of chargeable power in the secondary battery 20 and indicates how much power can be charged in the secondary battery 20 at the present time. The chargeable power depends not only on the amount of power stored in the secondary battery 20 at the present time but also on the temperature of the secondary battery 20. Therefore, for example, a table in which the amount of power charged in the secondary battery 20, the temperature of the secondary battery 20, and the chargeable power specified from these is associated in advance is stored in the memory of the control unit 60. Thus, the chargeable power acquisition unit 63 can acquire the chargeable power. That is, in this case, the chargeable power acquisition unit 63 acquires the chargeable power by referring to the table using the amount of power stored in the secondary battery 20 and the temperature of the secondary battery 20 at this time.

  The chargeable power correction unit 64 corrects the chargeable power value acquired by the chargeable power acquisition unit 63 so that the temporal variation of the power generated by the fuel cell satisfies a predetermined standard.

  Here, the reason why the chargeable power correction unit 64 performs correction will be described. When the secondary battery 20 is charged by the power generation of the fuel cell 10, the temporal fluctuation of the power charged in the secondary battery 20 causes the fluctuation of the operating point of the fuel cell 10. In particular, when charging the secondary battery 20 during rapid warm-up, since the required power is small, the temporal fluctuation of the charging power significantly affects the fluctuation of the operating point. The fluctuation of the operating point of the fuel cell 10 means that the conditions necessary for power generation (air flow rate and pressure, hydrogen amount, etc.) fluctuate. When the conditions necessary for power generation change, it is necessary to change the mechanical operation amount of the actuator of the auxiliary machinery 50 for operating the fuel cell 10 accordingly. Specifically, with changes in conditions necessary for power generation, for example, the air compressor rotation speed is changed to change the air flow rate, the valve opening / closing amount is changed to change the air pressure, or the hydrogen amount is changed. In order to change, an operation such as operating a hydrogen injector and blowing hydrogen is required. Therefore, the auxiliary machinery 50 is required to have response performance that can cope with fluctuations in the operating point.

  However, when it is difficult to ensure such response performance, there is a possibility that the chargeable power acquired by the chargeable power acquisition unit 63 cannot be charged. Even if such response performance can be ensured, the occurrence of fine movement of the actuators of the auxiliary machinery 50 due to fluctuations in the operating point causes deterioration in NV (Noise Vibration) performance. It will be.

  Therefore, in the present embodiment, the chargeable power value acquired by the chargeable power acquisition unit 63 is corrected so that the temporal fluctuation amount of the power generated by the fuel cell 10 is equal to or less than a predetermined fluctuation amount. To do. More specifically, the chargeable power correction unit 64 causes the temporal fluctuation amount of the electric power generated by the fuel cell 10 to be temporal fluctuation below the response frequency of the actuator of the driving auxiliary machinery 50. to correct. This correction is realized, for example, by performing an annealing process in which the chargeable power acquired by the chargeable power acquisition unit 63 is multiplied by a predetermined annealing constant (specifically, a value less than 1). it can.

  FIG. 3 is a graph showing an example of the temporal transition of the chargeable power value and the correction value when the secondary battery 20 is charged during rapid warm-up. In FIG. 3, the broken line graph indicates the chargeable power value acquired by the chargeable power acquisition unit 63, and the solid line graph indicates the correction value calculated by the chargeable power correction unit 64. As shown in FIG. 3, the correction value is suppressed from temporal variation. In charging the secondary battery 20, the electric power indicated by the correction value is charged. Therefore, by performing the correction, the temporal variation of the operating point is suppressed, and the temporal variation of the operation amount of the actuator is also suppressed.

  In the present embodiment, since the correction as described above is performed, the response performance required for the auxiliary machinery 50 can be suppressed. For this reason, a design freedom improves. Moreover, the above-mentioned deterioration of NV performance is also suppressed. In the following description, the corrected chargeable power calculated by the correction by the chargeable power correction unit 64 may be referred to as a “correction value”.

  The charge / discharge loss calculation unit 65 calculates the value of loss when the secondary battery 20 is charged and discharged with the power of the correction value. Hereinafter, the loss value when the power of the correction value is charged and discharged with respect to the secondary battery 20 may be referred to as a “charge / discharge loss value”. The charge / discharge loss calculation unit 65 uses the internal resistance value of the secondary battery 20 to calculate the loss due to the internal resistance accompanying the charge / discharge of the electric power indicated by the correction value. Note that the temperature characteristics of the internal resistance of the secondary battery 20 are stored in advance in the memory of the control unit 60. For this reason, the internal resistance value is specified by the temperature of the secondary battery 20 acquired by the temperature acquisition unit 61.

  The heat loss calculation unit 66 calculates the value of heat loss when the fuel cell 10 generates the same amount of power as the correction value during normal operation. Hereinafter, the value of heat loss when the fuel cell 10 generates the same amount of power as the correction value during normal operation may be referred to as “heat loss value”. The heat loss calculation unit 66 calculates a heat loss value by using previously known characteristics of the fuel cell 10.

  The charge determination unit 67 compares the charge / discharge loss value calculated by the charge / discharge loss calculation unit 65 with the heat loss value calculated by the heat loss calculation unit 66. And the charge determination part 67 permits the charge to the secondary battery 20 at the time of a low efficiency driving | operation, when a heat loss value is larger than a charge / discharge loss value. On the other hand, when the charge / discharge loss value is greater than or equal to the heat loss value, the charge determination unit 67 prohibits charging of the secondary battery 20 during low-efficiency operation. The charge determination unit 67 notifies the operation control unit 62 of the determination result.

  As described above, when the charging of the secondary battery 20 is permitted, the operation control unit 62 uses the power value obtained by adding the correction value to the required power value, and the generated power value of the fuel cell 10 during the low-efficiency operation. Set as. In other words, when the charging to the secondary battery 20 is permitted, the operation control unit 62 adds the correction value to the generated power value when performing the low-efficiency operation without charging the secondary battery 20. Low-efficiency operation involving charging of the secondary battery 20 is performed so that the value becomes the generated power value of the fuel cell 10. Further, when charging to the secondary battery 20 is prohibited, the operation control unit 62 sets the required power value as the generated power value of the fuel cell 10 during the low efficiency operation. In other words, the operation control unit 62 performs low-efficiency operation without charging the secondary battery 20 so that the required power value becomes the generated power value of the fuel cell 10 when charging to the secondary battery 20 is prohibited. I do.

  FIG. 4 is a graph showing a breakdown of electric power (FC electric power) of the fuel cell 10 at the time of rapid warm-up. In FIG. 4, the left graph is a graph showing an example of the breakdown of electric power when performing rapid warm-up without charging. In this graph, the power of the fuel cell 10 is divided into heat loss, power to the motor 40 (drive power), and power to the auxiliary devices 50 (auxiliary power). The middle graph is a graph showing an example of the breakdown of power when rapid warm-up is performed with charging of the power of the correction value. In this graph, the power of the fuel cell 10 is divided into heat loss, drive power, auxiliary power, power to the secondary battery 20, and charge / discharge loss. The graph on the right is a graph showing an example of the breakdown of power when both rapid warm-up without charging and power generation by normal operation of power of the correction value are performed. In this graph, the power of the fuel cell 10 includes heat loss corresponding to drive power and auxiliary power, drive power, auxiliary power, power to the secondary battery 20, and power to the secondary battery 20. It is divided into the corresponding heat loss.

  In the present embodiment, when the heat loss shown in the right graph is larger than the charge / discharge loss shown in the middle graph of FIG. 4, the low efficiency operation represented by the power breakdown in the middle graph is performed. Is called. As a result, the same heat loss as in the case of low-efficiency operation without charging (see the graph on the left in FIG. 4) can be used in comparison with the case of low-efficiency operation without charging.

  Next, a warm-up method of the fuel cell system 1 will be described. FIG. 5 is a flowchart showing an operation example of the fuel cell system 1. Hereinafter, the operation of the fuel cell system 1 will be described along the flowchart.

  In step 10 (S10), the temperature acquisition unit 61 acquires the temperature of the secondary battery 20 and the temperature of the fuel cell 10.

  Next, in step 11 (S11), the operation control unit 62 determines whether or not rapid warm-up is necessary. Specifically, the operation control unit 62 determines whether or not the temperature of the fuel cell 10 acquired in step 10 is equal to or lower than a predetermined temperature. When the temperature of the fuel cell 10 is equal to or lower than the predetermined temperature, the process proceeds to step 12 and the process of the flow for performing the rapid warm-up is performed. When performing the rapid warm-up, a series of processes after Step 12 are repeated every unit time. On the other hand, when the temperature of the fuel cell 10 is not equal to or lower than the predetermined temperature, the operation control unit 62 determines that rapid warm-up is not necessary, and the process returns to step 10.

In step 12 (S12), the chargeable power acquisition unit 63 acquires the current chargeable power _{W in} the secondary battery 20.

In step 13 (S13), the charging electric power correcting unit 64 corrects the W _in the annealing process, to calculate the corrected chargeable power W. That is, a correction value is calculated. FIG. 6 is a graph for explaining correction by the chargeable power correction unit 64. 6, the left graph is a graph showing an example of the magnitude of the current processing cycle current chargeable obtained in step 12 the power W _in. The middle graph is a graph showing an example of the magnitude of the corrected chargeable power W _prev obtained in step 13 in the previous processing cycle. The right graph is a graph showing an example of the magnitude of the corrected chargeable power W obtained in step 13 in the current processing cycle. As shown in FIG. 6, the correction suppresses fluctuations in the chargeable power from the previous processing cycle.

In step 14 (S14), the charge / discharge loss calculation unit 65 calculates the loss L _batt lost due to the charge / discharge of the chargeable power W. That is, the charge / discharge loss value is calculated.

In step 15 (S15), the heat loss calculation unit 66 calculates a heat loss L _fc when the amount of charge equal to the chargeable power W is to be covered by power generation by normal operation of the fuel cell 10. That is, the heat loss value is calculated.

In step 16 (S16), the charge determination unit 67 compares L _batt and L _fc and determines whether L _fc is larger than L _batt . If L _fc is larger than L _batt , the process _proceeds to step 17. When L _fc is not larger than L _batt , the operation control unit 62 sets the required power value as the generated power value of the fuel cell 10 during the low-efficiency operation, and the low-efficiency without charging the secondary battery 20 Do the driving. When L _fc is not larger than L _batt , the processing after step 12 is performed again in the next cycle.

  In step 17 (S17), the operation control unit 62 sets the power value obtained by adding the chargeable power W to the required power value as the power generation power value of the fuel cell 10 during the rapid warm-up, and sends it to the secondary battery 20. Low-efficiency operation with charging. After step 17, the processing after step 12 is performed again in the next cycle.

  FIG. 7 is a schematic diagram comparing the case where the secondary battery 20 is charged and the case where the secondary battery 20 is not charged during rapid warm-up. In FIG. 7, a graph represented by a solid line shows the IV characteristics of the fuel cell 10. Moreover, the graph represented by the broken line is an equal power curve representing the available power generated by the fuel cell 10 when performing rapid warm-up with charging of the secondary battery 20 as described above. A point P1 on the graph represented by a broken line indicates an operating point of the fuel cell 10 when performing rapid warm-up with charging of the secondary battery 20. Therefore, the area of the rectangular frame line with the point P1 as the apex corresponds to the amount of heat generated when rapid warm-up involving charging of the secondary battery 20 is performed. The graph represented by the alternate long and short dash line is an equal power curve representing the available power generated by the fuel cell 10 when performing rapid warm-up without charging the secondary battery 20. A point P2 on the graph represented by the alternate long and short dash line indicates an operating point of the fuel cell 10 when rapid warm-up without charging the secondary battery 20 is performed. Therefore, the area of the rectangular frame line having the point P2 as the apex corresponds to the amount of heat generated in the case of performing rapid warm-up without charging the secondary battery 20. In FIG. 7, the area of the rectangular frame line having the operating point P1 as the apex is equal to the area of the rectangular frame line having the operating point P2 as the apex. That is, the operating point P1 and the operating point P2 are both operating points for obtaining the same calorific value. During rapid warm-up, because of low efficiency operation, the operating points P1 and P2 are located below the IV characteristics indicated by the solid line graph as shown in FIG.

  As shown in FIG. 7, in the fuel cell system 1, by charging the secondary battery 20 at the time of rapid warm-up, more generated power can be obtained with the same calorific value as when charging is not performed. That is, the power generation efficiency is improved.

  The fuel cell system 1 has been described above. In the fuel cell system 1, as described above, when the heat loss value is larger than the discharge loss value, the secondary battery 20 is charged during the rapid warm-up. That is, when the power generation efficiency is reduced due to charge / discharge loss due to the internal resistance of the secondary battery 20, the secondary battery 20 is not charged during the rapid warm-up. For this reason, it is possible to efficiently perform warm-up and use power. That is, according to the fuel cell system 1, when the secondary battery is charged during normal operation, the energy lost due to heat loss is effectively utilized as the amount of heat during rapid warm-up, and the secondary battery during rapid warm-up. It is possible to charge the battery and efficiently perform warm-up and use of power. Further, as described above, the correction of the chargeable power correction unit 64 can suppress temporal fluctuations in the operating point of the fuel cell 10 due to charging. For this reason, the response performance requested | required of an actuator can be suppressed.

  By the way, unlike the fuel cell system 1 according to the present embodiment, assuming a fuel cell system that does not charge the secondary battery at the time of rapid warm-up in any case, the following problems are assumed. Occurs. The fuel cell system assumed here will be referred to as a system according to a comparative example. In the system according to the comparative example, when the ignition switch OFF signal (system stop request) is detected during rapid warm-up, the system stops without charging the secondary battery. And the system concerning a comparative example will wait for the next starting, without charge to a secondary battery. Here, when the power stored in the secondary battery is small, the discharge voltage of the secondary battery may be lower than the operation guarantee voltage inherent to the secondary battery at the next start-up. That is, the secondary battery may be deteriorated. In order to prevent this, even if the user turns off the ignition switch, rapid warm-up is continued, and then the secondary battery is charged by power generation by normal operation, and sufficient power is charged for the next start-up. It is conceivable to control the fuel cell system to stop later. However, in the case of such control, even after the user performs an operation of turning off the ignition switch, the system continues to operate for a while, which gives the user a sense of incongruity. For this reason, this control is not preferable.

  On the other hand, according to the fuel cell system 1 according to the present embodiment, the secondary battery 20 can be charged during the rapid warm-up, so that the ignition switch is turned off by the user during the rapid warm-up. However, it is possible to suppress the discharge voltage of the secondary battery from being lower than the operation guarantee voltage at the next start-up. Therefore, deterioration of the secondary battery 20 can be suppressed.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. For example, in the above-described embodiment, the chargeable power value acquired by the chargeable power acquisition unit 63 is corrected. However, this correction may be omitted. That is, each of the charge / discharge loss calculation unit 65, the heat loss calculation unit 66, the charge determination unit 67, and the operation control unit 62 is based on the chargeable power value acquired by the chargeable power acquisition unit 63 instead of the correction value. Processing may be performed. That is, in this case, in the description of the above embodiment, the charge / discharge loss value is the loss when the secondary battery 20 is charged and discharged with the chargeable power value acquired by the chargeable power acquisition unit 63. Value. Similarly, the heat loss value can be read as the value of heat loss when the fuel cell 10 generates the same amount of power as the chargeable power value acquired by the chargeable power acquisition unit 63 during normal operation. . Therefore, in this case, when the heat loss value is larger than the charge / discharge loss value, the operation control unit 62 sets the generated power value when performing low-efficiency operation without charging the secondary battery 20. Low-efficiency operation involving charging of the secondary battery is performed so that the power value obtained by adding the chargeable power value becomes the generated power value.

DESCRIPTION OF SYMBOLS 1 Fuel cell system 10 Fuel cell 15, 25 Temperature sensor 20 Secondary battery 30 Power distribution part 40 Motor 50 Auxiliary equipment 60 Control part 61 Temperature acquisition part 62 Operation control part 63 Chargeable power acquisition part 64 Chargeable power correction part 65 Charge / discharge loss calculation unit 66 Heat loss calculation unit 67 Charge determination unit

Claims (1)

A fuel cell system warm-up method for warming up a fuel cell by low-efficiency operation with lower power generation efficiency than normal operation,
Obtain a rechargeable power value that is the value of rechargeable power in the secondary battery,
Calculating a charge / discharge loss value that is a loss value when charging and discharging the power of the chargeable power value with respect to the secondary battery;
Calculating a heat loss value, which is a heat loss value when the fuel cell generates power of the same amount as the chargeable power value during the normal operation;
When the heat loss value is greater than the charge / discharge loss value, a power value obtained by adding the chargeable power value to the generated power value when the low-efficiency operation is performed without charging the secondary battery. A method for warming up the fuel cell system, wherein the low-efficiency operation accompanied by charging of the secondary battery is performed so that becomes a generated power value.

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