JP5470818B2 - Fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell system, and more particularly to a fuel cell system with improved transient response of reactant supply to a fuel cell.

In a polymer electrolyte fuel cell using hydrogen gas as a fuel gas and air as an oxidant gas, a cathode pressure regulating valve is provided so as to promote the discharge of residual gas inside the cathode of the fuel cell when the load on the fuel cell increases rapidly. There is known a fuel cell system for controlling (for example, Patent Document 1). In particular, when the oxygen concentration of the cathode is estimated and the oxygen concentration is estimated to be low, the rate of closing the pressure regulating valve is decreased to delay the pressure increase of the cathode, and the gas having a low oxygen concentration is quickly discharged from the cathode, It is trying to improve the load transient response of the fuel cell output.
Japanese Patent Laying-Open No. 2005-339845 (page 17, FIG. 6)

  However, in the above prior art, when a disturbance is applied to the pressure control system or a characteristic variation of the system occurs, the cathode pressure deviates from the target value, and the differential pressure between the anode and the cathode As a result, the membrane electrode assembly (MEA) of the polymer electrolyte fuel cell is subjected to excessive stress, which may cause deterioration of the membrane electrode assembly.

  In order to solve the above-described problems, the present invention includes a fuel cell system control unit that includes a system required target value generation unit, a target value generation unit, and an operation amount generation unit.

The system required target value generating means is configured to respond to a load request for the fuel cell, and a first target value that is a target value of the first state quantity of the reactant of the fuel cell is different from the first state quantity. A second target value that is a target value of the state quantity is generated.

Target value generating means includes a first target value based on the second target value, a correction value in the form of the modified second target value of the first target value correcting a correction value of the first target value and the second target value Generate. The operation amount generating means calculates the first operation amount and the second operation amount based on the corrected first target value and the corrected second target value.

The target value generating means generates the corrected first target value so that the corrected first target value matches or approximates the first target value, and the corrected second target value matches or approximates the second target value. First target correction value generating means for generating a first target correction value according to the degree of divergence between the corrected second target value and the second target value is generated, and the first target correction value is generated. The gist is to generate the corrected first target value based on the first target correction value and the first target value generated by the generating means .

  According to the present invention configured as described above, when the fuel cell load increases rapidly, for example, when the two state quantities of air pressure and flow rate are changed from a small value to a large value, a disturbance is applied to the pressure control system. When the system characteristics change or the like occurs, the cathode pressure deviates from the target value, and an increase in the differential pressure between the anode and the cathode can be prevented. As a result, there is an effect that it is possible to prevent excessive stress from being applied to the membrane electrode assembly (MEA) of the solid polymer fuel cell, thereby deteriorating the membrane electrode assembly.

  In the present invention, the state quantity of the reactant to be supplied to the fuel cell is brought close to the target value, and when there is no disturbance or characteristic fluctuation, the operation quantity in the transient state or the value related to the operation quantity becomes a desired value. If a disturbance target or a characteristic fluctuation occurs when a correct target value of the state quantity is generated, the disturbance or characteristic fluctuation is a state quantity of the reactant rather than setting the manipulated variable or the value related to the manipulated variable to a desired value. Disclosed is a fuel cell system capable of generating an operation amount for reducing the influence on the reaction mass and bringing the reactant state quantity close to the target value.

  According to the present invention, the target value can be generated without changing any operation amount generation unit that brings the measured state quantity close to the target value. Therefore, the feature of the operation amount generation unit can be utilized. When the manipulated variable generation unit is a feedback control system, the robustness and target value tracking performance of the feedback control system can be utilized. Therefore, since the change time of the target value can be performed without considering the influence of disturbance or characteristic fluctuation, the state quantity of the reactant can be changed more rapidly than in the prior art.

Reference example

Next, a reference example of the present invention will be described in detail with reference to the drawings. In the reference example , the system required target value generation unit includes a first target value that is a target value of the first state quantity of the reactant of the fuel cell and a target value of the second state quantity that is different from the first state quantity. The desired amount of the operation-related amount related to at least one of the second target value, the first operation amount that is the operation amount of the reactant supply means, and the second operation amount that is the operation amount of the reactant state adjustment means The desired operation-related quantity is generated. The target value generation unit corrects the corrected first target value and the corrected value of the second target value, which are correction values of the first target value, based on the first target value, the second target value, and the desired operation related amount. A second target value is generated and output to the operation amount generation unit.

  FIG. 1 is a system configuration diagram showing a configuration example of a fuel cell system to which the present invention is applied. In FIG. 1, a fuel cell (fuel cell main body) 1 is, for example, a solid polymer fuel cell. Hydrogen gas as a fuel gas is supplied to an anode, and air as an oxidant gas is supplied to a cathode. Progress and generate electricity.

Anode (hydrogen electrode): H ₂ → 2H ⁺ + 2e ⁻ (Chemical formula 1)
Cathode (oxygen electrode): 2H ⁺ + 2e ⁻ + (1/2) O ₂ → H ₂ O (Chemical formula 2)
Hydrogen supply to the anode is performed from the hydrogen tank 2 through the hydrogen tank main valve 3, the pressure reducing valve 4, and the hydrogen supply valve 5. The high pressure hydrogen supplied from the hydrogen tank 2 is mechanically reduced to a predetermined pressure by the pressure reducing valve 4, and the hydrogen pressure in the fuel cell is controlled to a desired hydrogen pressure by the hydrogen supply valve 5. A hydrogen circulation device 7 using a pump or the like is installed to recycle hydrogen that has not been consumed at the anode through the hydrogen circulation path 24. The hydrogen pressure of the anode is controlled by driving the hydrogen supply valve 5 by feeding back the hydrogen pressure detected by the pressure sensor 6a. By controlling the hydrogen pressure to a desired target pressure, the hydrogen consumed by the fuel cell is automatically compensated.

  The purge valve 8 is a valve that discharges the fuel gas discharged from the anode outlet to the exhaust hydrogen treatment device 9. The purge valve 8 is temporarily opened in the following cases. (1) Accumulation in the hydrogen system in order to increase the hydrogen partial pressure by reducing the concentration of impurity gas such as nitrogen accumulated in the anode and hydrogen circulation device 7 and the hydrogen circulation path 24 (referred to as hydrogen system) The discharged impurity gas is discharged. (2) Blow water clogged in the gas flow path in the anode to restore the cell voltage. (3) When the fuel cell system is started, in order to replace the hydrogen system with hydrogen, gas such as air in the hydrogen system is discharged.

  The exhaust hydrogen treatment device 9 dilutes with air so that the hydrogen concentration of the gas discharged from the purge valve 8 is less than the combustible concentration of hydrogen, or reacts hydrogen and air to burn and discharge the hydrogen concentration. Lower.

  Air to the cathode is supplied by a compressor 10a driven by a built-in motor. The inverter 10b incorporates a control microcomputer (hereinafter abbreviated as a microcomputer) and controls the rotation speed of the built-in motor of the compressor 10a.

  The humidifier 11 humidifies the air supplied from the compressor 10 a and supplies it to the cathode of the fuel cell 1. The air pressure and air flow supplied to the cathode are detected by the pressure sensor 6b and the flow sensor 6c, respectively. The controller (fuel cell system control unit) 30 feeds the air pressure detected by the pressure sensor 6b and the air flow rate detected by the flow sensor 6c to control the air pressure regulating valve 12 and the inverter 10b, thereby supplying the cathode to the cathode. The air is controlled so as to have a target air flow rate and a target air pressure.

  The air pressure regulating valve 12 is hereinafter referred to as an air pressure regulating valve together with a motor that drives the valve and a microcomputer that controls the valve opening degree. The microcomputer of the inverter 10b and the microcomputer of the air pressure regulating valve 12 may be removed if not necessary.

  Cooling water to a cooling water flow path of the fuel cell 1 (not shown) is supplied by a cooling water pump 13. The three-way valve 16 switches or diverts the flow path of the cooling water between the direction of the radiator 17 and the direction of the bypass flow path 19 that bypasses the radiator 17. The radiator fan 18 cools the cooling water by passing air through the radiator 17. The temperature of the cooling water is detected by the temperature sensor 14 at the fuel cell inlet and the temperature sensor 15 at the fuel cell outlet, and the controller 30 drives the three-way valve 16 and the radiator fan 18 based on these. adjust.

  The power manager 20 is a device that extracts the output from the fuel cell 1 and supplies the output (current or electric power) extracted from the fuel cell to a vehicle drive motor, storage battery, or the like (not shown). The power manager 20 is a DC / DC converter or a combination of a DC / DC converter and a DC / AC inverter. The voltage sensor 21 a detects the stack voltage value of the fuel cell 1, and the current sensor 21 b detects the current value extracted from the fuel cell 1.

The controller 30 controls the entire fuel cell system and is a fuel cell system control unit in the present reference example, and includes a microcomputer having a CPU, a program ROM, a working RAM, and a peripheral interface. The controller 30 is connected to a key switch 22 for instructing on / off of the fuel cell system and an accelerator opening sensor 23 for detecting the accelerator opening.

FIG. 2 is a main part configuration diagram of the controller (fuel cell system control unit) 30 in the present reference example, and is an example used for supply control of air as a reactant. In FIG. 2, the fuel cell system control unit 30 includes a system required target value generation unit 31, a target value generation unit 32, and an operation amount generation unit 33.

  The system required target value generation unit 31 is different from the first target value (mass flow rate) that is the target value of the first state quantity of the reactant and the first state quantity in response to the load request to the fuel cell 1. The second target value (pressure) that is the target value of the second state quantity, the first operation amount that is the operation quantity of the compressor (reactive substance supply unit) 10a, and the air pressure regulating valve (reactive substance state quantity adjustment unit) 12 A desired operation related amount that is a desired amount of the operation related amount related to at least one of the second operation amount that is the operation amount is generated.

  More specifically, the desired operation-related amount may be a desired opening that is a desired operation amount of the air pressure regulating valve 12, an air flow rate that passes through the air pressure regulating valve 12, or an air pressure regulating valve. Twelve channel cross-sectional areas may be used.

  Based on the first target value, the second target value, and the desired operation-related amount, the target value generation unit 32 uses the corrected first target value that is the correction value of the first target value and the correction value of the second target value. A certain corrected second target value is generated.

  More specifically, the target value generation unit 32 generates a corrected first target value so that the corrected first target value matches or approximates the first target value, and the corrected second target value matches the second target value. Alternatively, the corrected first target value is generated in a transient state in which the corrected first target value and the corrected second target value are close to the first target value and the second target value, respectively, while the corrected second target value is generated so as to approximate. Matches or approximates the first target value, the corrected second target value matches or approximates the second target value, and the operation-related amount can match or approximate the desired operation-related amount Generates a corrected first target value or a corrected second target value such that the operation-related quantity matches or approximates the desired operation-related quantity.

  The operation amount generating unit 33 is configured so that the first state quantity (mass flow rate) and the second state quantity (pressure) detected by sensors (not shown) are respectively the corrected first target value and the corrected second target value. The first operation amount and the second operation amount are calculated.

  FIG. 3 is a main part configuration diagram illustrating the configuration of the target value generation unit 32 in FIG. The target value generating unit 32 includes a first target correcting unit 41, a desired operation related amount limit value generating unit 42, an estimated operation related amount generating unit 43, an estimated operation related amount limiting unit 44, and a corrected second target generating unit. 45.

  The first target correction unit 41 calculates a corrected first target value (flow rate target value) based on the first target value. The desired operation related amount limit value generation unit 42 calculates a limit value based on the first target value and the desired operation related amount. The estimated operation related amount generation unit 43 calculates an estimated operation related amount based on the second target value and the corrected second target value. The estimated operation related amount limiting unit 44 calculates the limited operation related amount based on the estimated operation related amount and the limit value. The corrected second target generation unit 45 generates a corrected second correction value (pressure target value) based on the limited operation related amount.

  The desired operation-related amount limit value generation unit 42 generates a necessary operation-related amount based on the first target value, and a first limit based on the desired operation-related amount and the required operation-related amount. A first limit value generating unit 47 that generates a value, and a first comparison operation unit 48 that generates a limit value by subtracting the necessary operation-related amount from the first limit value.

  The estimated operation related amount generation unit 44 generates an estimated operation related amount so that the corrected second target value matches or approximates the second target value, and the desired operation related amount limit value generation unit 42 determines the estimated operation related amount limit. When the limit value is selected as the limit operation-related amount in the unit 44, a limit value is generated in a direction in which the corrected second target value is not changed or increased, and the estimated operation-related amount limit unit 44 When the corrected second target value is likely to increase as the limited operation-related amount is small, when the estimated operation-related amount is smaller than the limit value, the limited operation-related amount is set as the limit value, and the estimated operation-related amount is larger than the limit value Uses the restricted operation-related amount as the estimated operation-related amount, and the larger the restricted operation-related amount, the easier the corrected second target value becomes. If the estimated operation-related amount is greater than the limit value, the restricted operation-related amount is the limit value. And, when the estimated operation-related quantity is less than the limit value as the estimated operation-related amount of restricted operation-related quantity.

  When the desired operation related amount is generated as the first limit value in the first limit value generating unit 47, the operation related amount approaches the desired operation related amount in the restricted state, and the corrected second target value becomes the second target value. As the value approaches, the estimated operation-related amount increases, and the corrected second target value approaches the second target value.

  In addition, when the corrected second target value that causes the operation-related amount to approach the desired operation-related amount is generated, the required operation-related amount is determined when the corrected second target value deviates from the second target value. Alternatively, the correction-related operation-related quantity is selected as the limit value.

  In the target value generation unit 32 of FIG. 3, the corrected second target value, which is the output of the corrected second target generation unit 45, is fed back to the estimated operation related amount generation unit 43, so that the second target value and the corrected second target value are obtained. By calculating the estimated operation related amount from the deviation, the estimated operation related amount is calculated so that the corrected second target value approaches the second target value. Further, by limiting the estimated operation-related amount with a limit value, when this limitation is made, the second operation amount or the second operation-related amount generated by the subsequent operation amount generation unit 33 approaches the limit value. It becomes like this.

Next, the operation of the controller (fuel cell system control unit) 30 in this reference example will be described with reference to the flowcharts of FIGS. 4, 10, 11, and 13. FIG. 4 is a main flowchart of the controller 30 and shows only the part related to the present invention. This procedure is repeatedly executed every predetermined time (for example, every 1 ms). Here, a fuel cell vehicle in which the fuel cell system shown in FIG. 1 is mounted on a vehicle will be described as an example. Further, FIG. 15, FIG. 16, and FIG. 17 show block diagrams of this reference example.

  In the following description, the present invention is applied to the supply control of the reactant supplied to the cathode, the air supplied to the cathode as the reactant, the air flow rate (mass flow rate) value as the first state quantity of the reactant, The air pressure value is used as a two-state quantity. However, the present invention is not limited to the air supply, and it goes without saying that the present invention can be similarly applied to the hydrogen control supplied to the anode as a reactant. In this case, the hydrogen flow rate (mass flow rate) value as the first state quantity of the reactant, the hydrogen pressure value as the second state quantity of the reactant, the rotation speed of the hydrogen circulation device 7 as the first manipulated variable, and the hydrogen as the second manipulated variable The opening degree of the supply valve 5 can be considered.

  In FIG. 4, first, in step (hereinafter, step is abbreviated as S) 001, a load request to the fuel cell 1 is detected. For this purpose, the detected value of the accelerator opening sensor 23 connected to the controller 30 is read into the controller 30 and a control table stored in advance in the controller 30 is searched to obtain a load request from the accelerator opening. An example of this control table is shown in FIG. The control table in FIG. 5 may be determined in view of, for example, the characteristics of the vehicle, the maneuverability of the vehicle, the riding comfort, and the like that are to be realized as a fuel cell vehicle. You can actually drive various patterns and choose the most suitable one as a result of trial and error. The load request may be considered as power generated by the fuel cell, for example.

  Next, in S002, a system required target air flow rate that is a target value of the air flow rate required for the fuel cell 1 to generate electric power is determined based on the load request. For example, a control table as shown in FIG. 6 may be used for the conversion from the load request to the system required target flow rate. The values in the control table of FIG. 6 may be set so that the fuel cell can actually generate sufficient power by conducting an experiment. Similarly, when the air pressure is changed based on, for example, a load request, a system required target pressure that is a target value of the air pressure is also set. At this time, it can be easily realized by using the control table as shown in FIG. 7 obtained by the same method as that for obtaining the control table as shown in FIG.

  In S002, a desired operation related amount is generated. This may be considered as a desired value of the opening of the air pressure regulating valve 12, the air flow rate passing through the air pressure regulating valve 12, or the air flow rate passing through the fuel cell 1, for example. Hereinafter, a case where the desired operation related amount is the air pressure regulating valve opening will be described.

  When it is possible to approach the opening desired to be realized by the air pressure regulating valve 12, a desired operation related amount that is a desired opening is generated. An example of determining the desired operation related amount is shown in FIGS. In FIGS. 8 and 9, the desired air pressure regulating valve opening or the desired air pressure regulating valve passage flow rate is set to increase as the idle stop time, which is the duration of the idle stop that ended immediately before, is longer. In this way, the desired operation-related amount may be set so that the air pressure regulating valve is opened according to the situation where the air pressure regulating valve is desired to be opened. For example, in the case where the oxygen concentration of the cathode is reduced, a corrected target pressure that greatly opens the air pressure regulating valve 12 according to the degree to which the oxygen concentration is reduced or is estimated to be reduced. The desired operation related amount may be set so as to generate the corrected target flow rate.

  One specific example of the operating state of the fuel cell in which the cathode oxygen concentration is presumed to decrease is when power generation is resumed after an idle stop in which the fuel cell power generation is temporarily stopped. The controller 30 has a so-called idle stop function. During the idle stop, the compressor 10a and the hydrogen circulation device 7 are stopped, the air pressure regulating valve 12 and the hydrogen supply valve 5 are closed, and the power extraction from the fuel cell 1 by the power manager 20 is stopped, which is necessary for the system. Electric power is controlled to be supplied from a power storage device (not shown).

  However, even during idle stop, a cross leak occurs in which hydrogen or hydrogen ions pass from the anode through the electrolyte membrane to the cathode inside the fuel cell 1. This cross leak causes a reaction between hydrogen and oxygen, and oxygen in the cathode is consumed by the reaction, so that the oxygen concentration decreases. It can be assumed that the longer the idle stop time, the lower the oxygen concentration at the cathode.

  In addition, when switching from a certain load state (low load state) to a high load state where more power is generated, it is estimated that the oxygen concentration at the cathode will also decrease, for example, when the accelerator is stepped on to accelerate the fuel cell vehicle. This is one of the operating states. In this case, the target value of the generated power, the target air pressure, and the target air flow rate also increase stepwise, so that the air pressure control valve operation amount is applied in the direction of closing the air pressure control valve 12 by the calculation of the feedback control system. In such a case, since the air pressure regulating valve 12 is in the closing direction, discharge of exhaust air is more likely to be hindered in a transient state than in a steady state. At this time, it can be presumed that the oxygen concentration in the fuel cell is temporarily low because the cathode oxygen is consumed by the generated current.

  In such a case, the present invention corrects the relationship between the load demand, the target air pressure and the target air flow rate, and generates the corrected target air pressure and the corrected target air flow rate, thereby generating the corrected target air pressure and the corrected target air flow rate. The air pressure control valve opening can be controlled to approach the desired operation related amount by the air pressure control valve operation amount generated by the calculation of the feedback control system that controls the air pressure and the air flow rate so that the target air flow rate is achieved. .

  In addition, when it is estimated that ice is generated inside the fuel cell 1, for example, at the time of start-up after leaving the fuel cell vehicle at an outside temperature of 0 ° C. or less, the air is similarly applied. What is necessary is just to produce | generate desired operation related quantity so that the pressure regulation valve 12 may become the opening degree by which discharge | emission of ice is promoted.

  In addition, if it is estimated that there is a lot of water or water vapor that will reduce the power generation efficiency of the fuel cell, the desired operation-related amount should be generated so that the opening degree will facilitate the discharge of water or water vapor. That's fine. Specifically, the air pressure adjustment valve 12 may be opened in the opening direction, or the air pressure adjustment valve 12 may be intermittently closed or opened to promote the discharge of water or ice from the fuel cell 1. The opening degree and period at this time may be determined so that power can be generated stably by experiment. On the other hand, when it is estimated that water or water vapor is low, the desired operation-related amount may be generated so that the opening degree is such that discharge of water or water vapor is inhibited. Specifically, the desired operation-related amount may be set to an opening degree in the direction in which the air pressure regulating valve 12 is closed. When it is not particularly necessary to discharge the air, it is possible to raise the air pressure in the shortest time by setting the desired operation amount to the fully closed state which is a physical limit value of the air pressure regulating valve.

  Next, in S003, a corrected target pressure and a corrected target flow rate are generated based on the system operation target pressure and the system request target flow rate generated in S002 based on the desired operation related amounts. The details of how to generate the corrected target pressure and the corrected target flow rate will be described later. While the corrected target pressure is close to the system required target pressure and the corrected target flow rate is close to the system required target flow rate, the air pressure adjustment valve opening is related to the desired operation. If the air pressure adjustment valve opening is close to the desired operation-related amount, a corrected target flow rate and a corrected target pressure are generated so that the air pressure adjustment valve opening cannot approach the desired operation-related amount. In this case, a corrected target pressure and a corrected target flow rate are generated such that the corrected target pressure approaches the system required target pressure and the corrected target flow rate approaches the system required target flow rate.

  In S004, the operation amount and the air pressure regulating valve of the compressor 10a are calculated using the air pressure value and the air flow value detected by the pressure sensor 6b and the flow sensor 6c, respectively, and the corrected target pressure value and the corrected target flow value calculated in S003. Twelve manipulated variables are calculated.

  FIG. 13 is a flowchart showing details of the operation amount generation in S004 of FIG. In FIG. 13, a pressure deviation which is a deviation between the air pressure value and the corrected target pressure value is calculated in S401. In S402, a flow rate deviation that is a deviation between the air flow rate value and the corrected target flow rate value is calculated. Either S401 or S402 may be calculated first. In S403, the operation amount of the compressor 10a and the operation amount of the air pressure regulating valve 12 are calculated based on the pressure deviation and the flow rate deviation.

  For example, the operation amount of the air pressure regulating valve 12 may be a target value that is transmitted to a motor that drives the air pressure regulating valve 12 and a microcomputer. The microcomputer that finally drives the air pressure regulating valve 12 includes a detection value of an opening degree sensor (for example, a potentiometer) that measures the opening degree of the air pressure regulating valve 12, and a target value transmitted from the fuel cell system control unit of the present invention. May be realized using a known control method such as PID control theory.

  For example, when the compressor command rotational speed is used as the operation amount of the compressor 10a, the command rotational speed is transmitted to the inverter 10b that controls the rotational speed of the compressor 10a. Inverter 10b uses the transmitted compressor command rotation speed as a target value, and applies torque to the motor that drives compressor 10a so that the rotation speed of compressor 10a becomes the compressor command rotation speed. At this time, the torque calculation method can be easily realized by using a known control method such as PID control theory or vector control. Of course, torque applied to the compressor 10a may be calculated instead of the compressor command rotational speed. This case can also be easily realized by using a known control theory such as PID control theory.

  At this time, if it is not necessary to particularly feed back the detection signals of the pressure sensor 6b and the flow rate sensor 6c, feed-forward control which is a known method can be used. In the present invention, a known control method may be used as a method for calculating the operation amount from the target value. Hereinafter, a case where feedback control is applied will be described.

  Hereinafter, the procedure for generating the corrected target pressure and the corrected target flow rate in S003 of FIG. 4 will be described in more detail with reference to FIGS.

  In S301 of FIG. 10, a limit value is generated. Details of the limit value generation procedure are shown in FIG. In S3011, the necessary operation related amount is generated based on the system required target flow rate. For this calculation, a transfer function from a target flow rate transmitted to the feedback control system to a target opening that is an operation amount to the air pressure control valve or a control function applied to the air pressure control valve motor by the controller of the air pressure control valve 12 is transmitted. This is performed using the function G1. If the response from the target opening commanded to the air pressure adjustment valve 12 to the actual opening is sufficiently faster than the response of the air pressure and air flow rate, a transfer function up to the target opening may be used. More accurately or when the above-described response is equivalent, a transfer function up to the operation amount applied to the air pressure regulating valve motor may be used. Whether the responsiveness is sufficiently fast is determined by comparing the step response time of the actual opening with respect to the target opening and the step response time of the actual pressure with respect to the target pressure, and comparing the time to reach the target value. If the response time is less than 1/3 of the pressure response time, it can be said that the response is sufficiently fast. Below, the case where the transfer function to the target opening degree which is the operation amount to an air pressure regulation valve is used is demonstrated.

  Here, when the desired operation related amount is not the opening of the air pressure regulating valve 12 but the passage flow rate of the air pressure regulating valve 12, the transfer function from the target flow rate to the air pressure regulating valve passage flow rate is used. Hereinafter, a case where the desired operation related amount is the opening of the air pressure regulating valve 12 will be described.

  This transfer function actually constitutes the fuel cell system shown in FIG. 1, and a transfer function G1 from the target flow rate to the manipulated variable to the air pressure regulating valve can be obtained using a known transfer function derivation method, for example, a system identification method. That's fine. Further, the transfer function G1 can be reduced in dimension using a known technique. In order to reduce the dimensions, for example, a mode censoring method can be used.

  Further, if necessary, a limit value can be calculated from the system required target flow rate by combining G1 and a transfer function M different from G1. How to determine M will be described later.

  The transfer function G1 obtained as described above is rewritten in the state space expression to generate a necessary operation related quantity. For the conversion from the transfer function to the state space representation, a method that has been shown for a long time in a known control technique may be used. For example, it can be expressed as (Equation 1) and (Equation 2) by performing a minimum realization.

x (k + 1) = A × x (k) + B × u (k) (Formula 1)
y (k) = C × x (k) + D × u (k) (Formula 2)
Where x is a state vector, u is a system required target flow rate, y is a necessary operation-related quantity, k is a parameter expressing the time for each control cycle, A is a system matrix, B is an input matrix, C is an output matrix, and D is It is a matrix or scalar obtained from the transfer function G1 as a direct matrix. If the initial value of x is not particularly required, all vector elements may be set to the initial value 0.

  Calculation may be performed by substituting the system required target flow rate for u (k) in (Equation 1) and (Equation 2), and y (k) may be generated as a necessary operation-related quantity.

Hereinafter, a reference example will be described in the case where the corrected second target value is likely to increase as the estimated operation related amount decreases.

  In step S3012, the desired operation related amount is compared with the necessary operation related amount. If the desired operation-related amount is not smaller than the required operation-related amount (if the desired operation-related amount is greater than or equal to the required operation-related amount), the process proceeds to S3013. If the desired operation-related amount is smaller than the necessary operation-related amount, the process proceeds to S3014.

  In S3013, the desired operation related amount is corrected. If S3013 is reached, the desired operation-related amount is greater than or equal to the required operation-related amount. In this case, if the corrected target pressure is generated such that the air pressure adjustment valve opening becomes the desired operation-related amount, the corrected target pressure is It will be away from the required target pressure. In this case, a procedure for correcting that the air pressure regulating valve opening approaches the desired operation-related amount is taken.

  In S3013, the limit value is set as a boundary value. Here, the boundary value is a value that increases the corrected target pressure or a value that does not change. For example, when the operation amount is 0 when it is desired to fully close the air pressure regulating valve, and when the operation amount is 1 when it is desired to be fully opened, the boundary value is set to 0, the required operation related amount, or the required operation related amount. For example, it may be brought closer to 0 with time.

  When the boundary value is set to 0, when the corrected target pressure and the corrected target flow rate are applied to the feedback control system such as the operation amount generation unit 33 in FIG. It means generating a corrected target pressure that can be closed. In this case, it may be used when it is desired that the corrected target pressure be brought closer to the system required target pressure in a shorter time than when the necessary operation-related amount is set as the limit value.

  When the boundary value is a required operation-related quantity, the cathode air pressure is not increased by stopping the correction target pressure from approaching the system required target pressure and not changing the correction target pressure. As a result of being controlled by the control, the air pressure regulating valve 12 is greatly opened. In this case, it may be used when priority is given to bringing the air pressure regulating valve 12 closer to the desired operation related amount than to bringing the corrected target pressure closer to the system required target pressure. In addition, when the required operation-related amount is Un, the limit value may be changed with time using an expression such as (Expression 3).

Un (1-1 / (1 + Ts)) (Formula 3)
Where T is the time constant and s is the Laplace operator. This is equivalent to subtracting the calculation result obtained by applying the necessary operation-related quantity to the primary low-pass filter from the necessary operation-related quantity. The time constant T is a value that determines how fast the limit value is to be set to 0 from the necessary operation-related amount, and approaches 0 in a shorter time as the value is closer to 0. When (Formula 3) is applied, the calculation result gradually approaches 0 from the necessary operation-related amount. For this reason, when the corrected target pressure and the corrected target flow rate generated using (Equation 3) are transmitted to the feedback control system, the operation amount of the air pressure regulating valve that approaches the desired operation related amount is calculated in the first half in the transient state. Thus, a corrected target pressure is generated in which the operation amount of the air pressure regulating valve is calculated such that the air pressure regulating valve approaches full closing over time. In this case, the temporal change of the corrected target pressure changes greatly with time.

  Furthermore, when it is desired to bring the corrected target pressure close to the system target pressure in the shortest time, the boundary value may be set to a negative value as small as possible. This may be the smallest value that can be handled in the calculation of the microcomputer constituting the controller 30. For example, if the microcomputer is 16 bits, it is -65535 (-(2 <16> -1)).

  In addition, even if the corrected target pressure deviates from the system required target pressure, if you want the air pressure adjustment valve opening to be the desired operation-related amount, set the limit value as the desired operation-related amount, or combine the above various values You can also. By performing the above setting, it is possible to generate a limit value in a direction in which the correction target pressure is not changed or increased.

  In S3014, [desired operation related amount-necessary operation related amount] is substituted for the limit value. In S3011 to S3014, the limit value of S301 is generated.

  In S302, the deviation between the system required target pressure and the corrected target pressure is calculated as in (Equation 4).

e = Rp0−Rp2 (Formula 4)
Here, Rp0 is the system required target pressure, Rp2 is the corrected target pressure, and e is the deviation.

  In step S303, based on the deviation e calculated in step S302, a virtual operation amount that makes the deviation e zero is generated. For this purpose, a known control method such as PID control theory may be used. Since the virtual operation amount is generated so that the absolute value of the deviation is reduced by this procedure, the absolute value of the deviation can be reduced, and the corrected target pressure can be brought close to the system required target pressure. If it is desired to match the system required target pressure, an integral operation may be performed. Since this is based on the PID control theory, details are omitted. Further, when using the optimal control theory or the like, the state quantity of the virtual control target described in detail in S307 may be used.

  In S304, a corrected target flow rate Rf1 is generated from the system required target flow rate Rf0. This procedure can be omitted if not necessary. For example, the generation may be performed using a transfer function Mf as shown in (Equation 5).

Rf1 = Mf * Rf0 (Formula 5)
However, Mf is a first-order low-pass filter as described above, and its time constant T may be determined by experiment, simulation, or the like. The closer T is to 0, the shorter the time during which the compressor speed increases, so the sound of the speed may be set while evaluating the loudness. If you are worried about the sound, increase T. If you are not concerned about the sound, you can reduce the time to increase the compressor speed by bringing T closer to 0.

  When this procedure is omitted, the system required target flow rate may be substituted for the corrected target flow rate. It goes without saying that the processing of S301, the serial processing of S302 and S303, and the processing of S304 can be performed in any order.

  In S305, the limit value generated in S301 is compared with the size of the virtual operation amount generated in S303. When the virtual operation amount is equal to or less than the limit value, the process proceeds to S306, and when the virtual operation amount is larger than the limit value, the process proceeds to S307.

  S306 is a case where it is determined in S305 that the virtual operation amount is equal to or less than the limit value. In this case, the virtual operation amount is limited to the limit value by substituting the limit value into the virtual operation amount. With this procedure, a corrected target pressure is generated so that the operation amount approaches the limit value when the corrected target flow rate and the corrected target pressure are applied to the operation amount generation unit 33 that performs the feedback control of FIG.

  Since the limit value is generated so that the corrected target pressure does not change or increases from S3011 to S3014, the corrected target pressure is generated even if the virtual operation amount generated in this procedure is used for generating the corrected target pressure in S307. Does not change or changes in an increasing direction. The direction of increasing here is that the correction target pressure may temporarily decrease when the limit value is continuously applied, but the correction target pressure takes a minimum value, and then the correction target pressure increases with time. It means to become. This concept is illustrated in FIG. FIG. 12 is a diagram showing the corrected target pressure value with respect to the limit value application duration time. In FIG. 12, there is a case where a limit value is applied as indicated by a broken line A to monotonously increase, and a minimum value is indicated as a solid line B.

  In S306, the integration calculation of the virtual operation amount calculation generated in S303 may be stopped. This can reduce the vibration of the corrected target pressure due to the virtual operation amount becoming the limit value by stopping the integral calculation. In addition to stopping the integration, various antiwindup techniques have been proposed, and it goes without saying that various antiwindup techniques can be applied in the present invention. For example, there is an anti-windup control system based on the left irreducible decomposition expression of the controller. In this case, the virtual operation amount can also be realized by using it as a feedback signal. A block diagram corresponding to the processing of S306 in this case is shown in FIG.

  In S307, a corrected target pressure is generated. The virtual manipulated variable U2 may be calculated as U2 in (Equation 7) and (Equation 8) realizing the transfer function shown in (Equation 6), and Rp2 (k) may be used as the corrected target pressure.

Rp2 = G2 x U2 (Formula 6)
x (k + 1) = A * x (k) + B * U2 (k) (Expression 7)
Rp2 (k) = C × x (k) + D × U2 (k) (Equation 8)
Where A, B, C, and D are matrices or scalars obtained from G2, k is a parameter that represents the time in each control cycle, x (k + 1) is a state vector, and all initial values are not required. The value of the element may be set to 0.

  G2 is a transfer function, which may be a transfer function approximating the transfer function from the manipulated variable to the air pressure regulating valve 12 to the corrected target pressure or the transfer function from the manipulated variable to the air pressure regulating valve 12 to the corrected target pressure. . At this time, if necessary, a transfer function to which another transfer function Mp is added may be G2.

  For example, Mp may be added in order to make it proper when the transfer function from the manipulated variable to the air pressure regulating valve 12 to the corrected target pressure is improper.

  When Mp is added, Mp ^ -1 may be added to M added to the transfer function G1 in (Expression 1) and (Expression 2). When Mf in (Equation 5) is used, Mf may be added to M added to G1.

  When the desired operation related amount is the air pressure regulating valve passage flow rate, G2 may be a transfer function from the air pressure regulating valve passage flow rate to the corrected target pressure.

The fuel cell system is operated by repeating the above procedure.
In this reference example, the target value generation method on the cathode side has been described, but the same can be said for the anode side.

Further, FIG. 15 shows a block diagram of a target value generator (target value generation unit 32) corresponding to generation of the corrected target flow rate and the corrected target pressure according to the control flowchart of the reference example.

  In FIG. 15, the target value generator inputs a system required target flow rate Rf0, a system required target pressure Rp0, and a desired air pressure regulating valve opening, and outputs a corrected target flow rate Rf1 and a corrected target pressure Rp2. 15 includes a function generator 61 based on the transfer function G1, a function generator 62 based on the transfer function Mf, a first limit value generator 63, a subtractor 64, a subtractor 65, and a function generation based on the transfer function K. 66, a limiter 67 for calculating a limit operation amount (limit opening of the air pressure regulating valve) U2, and a function generator 68 using a transfer function G2.

  In FIG. 15, the function generator 61 calculates a required opening degree U1 that is a required operation amount of the air pressure regulating valve 12 from the system required target flow rate Rf0. The function generator 62 calculates a corrected target flow rate Rf1 from the system required target flow rate Rf0. The first limit value generator 63 calculates the first limit value Umin0 from the required opening U1 of the air pressure regulating valve 12 calculated by the function generator 61 and the desired air pressure regulating valve opening.

The calculation content of the first limit value generator 63 is calculated by the following program, for example.
[Equation 1]
if desired air pressure adjustment valve opening <required opening Umin0 = desired air pressure adjustment valve opening
else if Required opening <Desired air pressure adjustment valve opening Umin0 = Required opening
end

  The subtractor 64 calculates a limit value [Umin0−U1] by subtracting the required opening degree U1 from the first limit value Umin0. The subtractor 65 calculates the deviation ep by subtracting the corrected target pressure Rp2 from the system required target pressure Rp0. The function generator 66 calculates a virtual opening degree U0 which is a virtual operation amount of the air pressure regulating valve from the deviation ep. The limiter 67 calculates a limit opening (limit operation amount) U2 in which the virtual opening U0 is limited to a limit value [Umin0−U1]. The function generator 68 calculates the corrected target pressure Rp0 from the limit opening degree U2.

  In the target value generator of FIG. 15, the corrected target pressure, which is the output of the function generator 68, is fed back to the subtractor 65, and the virtual manipulated variable is calculated from the deviation between the system required target pressure value and the corrected target pressure value. Thus, the virtual operation amount is calculated so that the corrected target pressure value approaches the system required target pressure value. Further, by limiting the virtual operation amount with the limit value, when this limitation is made, the second operation amount or the second operation-related amount by the operation amount generation unit at the subsequent stage comes close to the limit value.

  The correspondence between FIG. 3 and FIG. 15 is as follows. The first target value is the system required target flow rate Rf0, the second target value is the system required target pressure Rp0, the desired operation related amount is the desired air pressure adjustment valve opening, the corrected first target value is the corrected target flow rate Rf1, and the corrected second target value. Is the corrected target pressure Rp2. The first target correction unit 41 is a function generator 62, the necessary operation related amount generation unit 46 is a function generator 61, the first limit value generation unit 47 is a first limit value generator 63, and the first comparison calculation unit 48 is The subtractor 64, the estimated operation related quantity generating unit 43 is a subtractor 65 and a function generator 66, the estimated operation related quantity limiting unit 44 is a limiter 67, and the modified second target generating unit 45 is a function generator 68.

Further, it goes without saying that the configuration obtained by equivalently converting the block diagram of FIG. 15 is included in the present reference example , for example, FIG. 16 and FIG. FIG. 16 shows an example in which a subtracter 72 is arranged between the limiter 67 and the function generator 68 in place of the subtracter 64 of FIG. FIG. 17 shows an example in which a subtracter 74 for subtracting the required opening from the desired air pressure regulating valve opening is provided in place of the subtracter 64 of FIG.

Next, a time chart showing the present embodiment and the specific Comparative Examples are shown in FIGS. 18 and 19 show a case where the system required target value suddenly rises at time t0, (a) is the flow rate, (b) is the pressure, (c) is the air pressure adjustment valve opening (operation amount), ( d) indicates the operation-related quantities.

In FIGS. 18 and 19, thick solid lines in (a) and (b) are system required target values (target flow rate or target pressure) in the reference example and the comparative example. A thick broken line is a correction target value (correction target flow rate or correction target pressure) in the reference example. The state quantity detection value (flow rate detection value or pressure detection value) in the reference example as a result of applying the corrected target value to the feedback control system is indicated by a thick dashed line. Thin solid line is the state quantity detection value of the ratio Comparative Examples (detected flow rate value or the pressure detected value).

18 and FIG. 19 (c), the thick one-dot chain line is the operation amount of the air pressure regulating valve opening in the reference example, the thick two-dot chain line is the desired operation-related amount in the reference example, and the thin solid line is the comparative example. The amount of operation.

In the air pressure regulating valve opening in FIG. 18C, it can be confirmed that the operation amount of the reference example is the desired air pressure regulating valve opening from time t0 to time t1. In other respects, it can be seen that the amount of operation remains in the vicinity of the system required target pressure.

FIG. 18D shows a calculation result inside the target value generation of the reference example . The fine one-dot chain line is the necessary operation-related amount, the fine two-dot chain line is the restriction operation-related amount, and the thin broken line is the restriction value. From time t0 to time t1, the estimated operation-related amount is in a limit state where the limit value is set, and it can be confirmed that the operation amount is approaching the desired operation-related amount. In an area other than the period from time t0 to time t1, an estimated operation-related amount that approximates the corrected target pressure and the system required target pressure is generated.

FIG. 19 shows a case in which the disturbance in the reference example is applied and the pressure is lowered, and the air pressure control valve opening (operation amount) in FIG. 19C is temporarily reduced so as to cancel this disturbance. In the pressure of FIG. 19B, it is realized that priority is given to increasing the pressure reduced by disturbance rather than bringing the operation amount close to the desired operation-related amount.

According to the reference example described above, when the fuel cell load increases rapidly, for example, the two state quantities of the reactant supplied to the fuel cell are changed from a small value to a large value. If a disturbance is applied to the state quantity control system or system characteristics change, etc., the state quantity is set to the target value with priority given to controlling the state quantity of the reactants to the target value. When there is no disturbance or characteristic fluctuation, the desired operation-related amount can be achieved as long as possible while achieving the target value of the state quantity of the reactant according to the load demand. As a result, the transient response performance of the fuel cell output can be improved.

Further, according to this reference example, the first state quantity is the flow rate of the reactant and the second state quantity is the pressure of the reactant. When changing the two state quantities of flow rate and pressure from a small value to a large value, if a disturbance is applied to the pressure control system or flow control system or if system characteristics change, etc., Prioritizing controlling the pressure to the target value, the reactant pressure can deviate from the target value and prevent the fuel cell from deteriorating due to an increase in the pressure difference between the anode and the cathode. If there is not, control to achieve the desired operation-related amount as much as possible while achieving the target flow rate and pressure of the reactant according to the load demand, and improve the transient response performance of the fuel cell output I can do it There is an effect.

Further, according to this reference example, the desired operation-related amount is generated according to the operating state of the fuel cell. For example, when the load demand of the fuel cell shifts from a low load to a high load, At the time of resumption, etc., by generating a desired operation-related amount that increases the opening of the air pressure regulating valve, air with a low oxygen partial pressure is quickly discharged, and the oxygen partial pressure at the cathode is rapidly increased. There is an effect that power generation with good load response can be performed.

Further, according to this reference example, a desired operation-related amount is generated so that the reactant or water vapor or water or ice inside the fuel cell system is easily discharged through the reactant state quantity adjustment unit according to the operating state. Therefore, when water vapor, water, or ice is generated in the fuel cell system, these can be discharged through the reactant state quantity adjustment unit, and the operating state of the fuel cell can be quickly returned to the normal state. There is an effect.

Further, according to this reference example, the target value generation unit includes an estimated operation related amount generation unit, an estimated operation related amount limit unit, a modified second target generation unit, and a desired operation related amount limit value generation unit. The estimated operation related amount generation unit calculates an estimated operation related amount based on the second target value and at least the modified second target value, and the desired operation related amount limit value generation unit calculates the first target value and the desired operation related amount. The estimated operation related amount limiting unit calculates the limited operation related amount based on the estimated operation related amount and the limit value, and the modified second target generation unit calculates the limited operation related amount. Based on this, the second target correction value is generated. Further, the estimated operation related amount generation unit generates an estimated operation related amount so that the corrected second target value matches or approximates the second target value, and the desired operation related amount limit value generation unit generates the estimated operation related amount limit. When the limit value is selected as the limit operation-related amount in the part, the limit value in the direction in which the correction second target value is not changed or increased is generated, so that the correction target value is reliably set to the second target value. Can be matched or approximated to a value, and when the limit state is reached, the rate of change of the modified second target value decreases or does not change depending on the limit value, and the operation-related amount can approach the desired operation-related amount, When the limit state is not reached, the corrected second target value can be matched or approximated to the second target value by the estimated operation related amount, and the fuel cell can be operated in an appropriate state. There is an effect that becomes so that.

Further, according to the present reference example, the desired operation related amount limit value generation unit includes the necessary operation related amount generation unit, the first limit value generation unit, and the first comparison calculation unit, and the necessary operation related amount generation unit The required operation related amount is generated based on one target value, the first limit value generating unit generates a first limit value based on the required operation related amount and the desired operation related amount, and the first comparison operation unit Since the limit value is generated by adding and subtracting the limit value and the necessary operation-related amount, no special restriction is imposed on the first and second operation amounts. Therefore, the first state amount or the second state amount is caused by disturbance or the like. Is deviated from the corrected first target value or the corrected second target value, the first state quantity or the second state quantity is changed to the corrected first target value or the corrected first value rather than bringing the operation related quantity close to the desired operation related quantity. 2 It can be prioritized to approach the target value. For this reason, there is an effect that it is possible to avoid a situation in which the corrected second target value deviates from the second target value, and to bring the corrected second target value closer to the second target value.

Further, according to this reference example, the reactant state quantity adjusting unit is an air pressure regulating valve that changes the state quantity of the reactant by discharging the reactant from the part, and the desired operation related quantity is set as the reactant state quantity adjusting unit. By setting the flow rate when discharging the reactant (air), or the cross-sectional area of the flow path, or the cross-sectional area-related amount related to the cross-sectional area, the desired discharge flow rate, the desired flow path cross-sectional area, and the desired opening of the air pressure adjustment valve Both have the effect that the desired operation amount can be obtained.

Next, Embodiment 1 of the present invention will be described in detail with reference to the drawings. In Example 1, the system requests the target value generation unit comprises: a first target value is a target value of the first state amount of the reactants in the fuel cell, the target of the different second state quantity from the first state quantity The second target value that is a value is generated, and the desired operation-related amount as in the reference example is not essential. The target value generation unit obtains a corrected first target value that is a correction value of the first target value and a corrected second target value that is a correction value of the second target value based on the first target value and the second target value. Generate and output to the operation amount generator.

The overall configuration of the fuel cell system to which this embodiment is applied is the same as the reference example shown in FIG.

Figure 20 is a main configuration diagram of a controller (the fuel cell system control unit) 30 in the first embodiment, an example using the air supply control as reactants. In FIG. 20, the fuel cell system control unit 30 includes a system required target value generation unit 31a, a target value generation unit 32a, and an operation amount generation unit 33a.

The system request target value generation unit 31a corresponds to the system request target value generation unit 31 of the reference example , except that generation of the desired operation related amount is omitted. The operation amount generation unit 33a corresponds to the operation amount generation unit 33 of the reference example .

The system required target value generation unit 31a is different from the first target value (mass flow rate) that is the target value of the first state quantity of the reactant and the first state quantity in response to the load request to the fuel cell 1. A second target value (pressure) that is a target value of the second state quantity is generated. Similar to the reference example , the load request is obtained by searching a control map for obtaining a load request (generated power) with respect to the accelerator opening as shown in FIG. The first target value and the second target value, as in the respective reference examples, FIG. 6, based on a control map as shown in FIG. 7, is generated from the load request.

  Based on the first target value, the second target value, and the desired operation-related amount, the target value generating unit 32a uses the corrected first target value that is the corrected value of the first target value and the corrected value of the second target value. A certain corrected second target value and a corrected target current value that is a current value that the power manager 20 should extract from the fuel cell 1 are generated.

  The manipulated variable generation unit 33a includes a first state quantity (mass flow rate) and a second state quantity (pressure) detected by the air flow sensor 6c and the air pressure sensor 6b, respectively, as a corrected first target value and a corrected second target value. The first operation amount and the second operation amount are calculated so as to be a value. The first operation amount is an operation amount (for example, rotational speed) of the compressor (reactive substance supply unit) 10a, and controls the mass flow rate of air supplied from the compressor 10a to the air electrode of the fuel cell 1. The second operation amount is an operation amount (for example, valve opening degree) of the air pressure regulating valve (reactive substance state amount adjusting unit) 12 and controls the pressure of the air electrode of the fuel cell 1.

  FIG. 21 is a diagram illustrating the functional configuration of the target value generation unit 32a in FIG. 20 as a block diagram. Actually, it is realized by software of the controller 30. The target value generator 32a includes a corrected first target value generator 81, a corrected second target value generator 82, a first target correction value generator 83, an adder 84, a subtractor 85, a target current value. And a generation unit 86.

  The corrected second target value generating unit 82 generates a corrected second target value (pressure target value) based on the second target value (pressure). The subtracter 85 supplies a value obtained by subtracting the second target value from the corrected second target value to the first target correction value generation unit 83.

  The first target correction value generation unit 83 calculates a first target correction value based on a value obtained by subtracting the second target value from the corrected second target value. The adder 84 adds the first target value (flow rate) and the first target correction value, and supplies the corrected first target value, which is the addition result, to the corrected first target value generation unit 81. The corrected first target value generation unit 81 calculates a corrected first target value (flow rate target value) based on the corrected first target value.

  Further, the target current value generation unit 86 generates a corrected target current value that the power manager 20 should take out from the fuel cell 1 based on the corrected second target value and the first target correction value. The target current value generation unit 86 is a target value that is a target value of the generated power that is generated by limiting the reference target generated power that is a load request to the fuel cell 1 and the time change rate of the reference target power according to the accelerator operation. Generated power, a reference target current that is a target value of the fuel cell current for realizing the target generated power, and a corrected target current obtained by correcting the reference target current are generated. When generating the corrected target current, the target current value generating unit 86 increases the corrected target current with respect to the reference target current as the corrected second target value is larger or the first target correction value is smaller. Generate. For this reason, it becomes possible to perform power generation commensurate with the air pressure of the fuel cell, and it is possible to avoid power generation in a state where oxygen partial pressure is insufficient.

  FIG. 22 shows a target value generation unit that calculates a corrected target air flow rate (corresponding to the corrected first target value in FIG. 21) and a corrected target air pressure (corresponding to the corrected second target value in FIG. 21) in the target value generating unit 32a. It is a practical block diagram of 32a. In FIG. 22, the first state quantity, the first target value, and the corrected first target value are air flow values, and the second state quantity, the second target value, and the corrected second target value are air pressure values. Therefore, the first target correction including a derivative necessary for the corrected second target value (target air pressure) to follow the second target value (system required target air pressure), which cannot be obtained from time to time online. Without calculating the value, the correction value of the target flow rate can be calculated using the calculation result of the corrected target air pressure, the follow-up performance of the corrected first target value to the first target value, and the corrected second There is an effect that the follow-up performance of the target value to the second target value is improved.

  In FIG. 22, the target value generation unit 32a includes a system required target air flow rate that is the first target value generated by the system required target value generation unit 31a and a first target correction value generated by the first target correction value generation unit 83. The second target value generated by the system required target value generation unit 31a and the change rate limiter 81a that outputs the corrected target air flow rate by limiting the time change rate of the output of the adder 84. A rate-of-change limiter 82a that outputs a corrected target air pressure by limiting a time change rate of a certain system required target air pressure according to the corrected target air flow rate, and a pressure difference between the corrected target air pressure and the system required target air pressure. A subtractor 85 for calculating, and a first target correction value generating unit 83 for generating a first target correction value from the output of the subtractor 85.

  The first target correction value generating unit 83 includes a multiplier 83a that multiplies a constant P to convert the pressure difference calculated by the subtractor 85 into a flow rate, a limiter 83b that limits the output minimum value of the multiplier 83a to 0, Is provided.

  Here, the multiplier 83a and the limiter 83b correspond to the first target correction value generation unit 83 of FIG. That is, the first target correction value generation unit converts the pressure difference between the corrected target air pressure and the system required target air pressure into a flow rate correction value, and further limits the minimum value of the flow rate correction value to 0, thereby increasing the flow rate. Since correction is made only in the direction, there is an effect that it is possible to avoid inadvertently reducing the flow rate in order to reduce the pressure that is the second target value.

  The change rate limiter 81a is a change rate limiter that generates a corrected target air flow rate by limiting the time change rate of the sum of the system required target air flow rate and the first target correction value.

  The change rate limiter 82a is a limiter that increases the upper limit of the time change rate of the corrected target air pressure as the corrected target air flow rate increases. Therefore, the corrected target air pressure can be generated so that the upper limit of the time change rate of the corrected target air pressure, which is the corrected second target value, increases as the first target value or the first target correction value increases. There is an effect that it is possible to improve the tracking performance of the corrected first target value to the first target value and the tracking performance of the corrected second target value to the second target value.

Figure 23 is a configuration of a modification of Reference Example a combination of a target value generator 32 of the reference example and the first target correction value generating section 83 described with reference to FIGS. 21 and 22 of the embodiment 1 (83a, 83 b) FIG. Also in the reference example , the target air flow rate can be increased based on the difference between the system required target air pressure and the corrected target air pressure.

Next, FIG. 24, FIG. 25, with reference to the flowchart of FIG. 26, the operation controller (fuel cell system control unit) 30 of the first embodiment. FIG. 24 is a main flowchart of the controller 30 and shows only the part related to the present invention. This procedure is repeatedly executed every predetermined time (for example, every 1 ms). Further, here, an embodiment will be described by taking as an example a fuel cell vehicle in which the fuel cell system shown in FIG. 1 is mounted on a vehicle.

  In FIG. 24, first, in S101, a load request to the fuel cell 1 is detected. For this purpose, the detected value of the accelerator opening sensor 23 connected to the controller 30 is read into the controller 30 and a control table stored in advance in the controller 30 is searched to obtain a load request from the accelerator opening. An example of this control table is shown in FIG. The control table in FIG. 5 may be determined in view of, for example, the characteristics of the vehicle, the maneuverability of the vehicle, the riding comfort, and the like that are to be realized as a fuel cell vehicle. You can actually drive various patterns and choose the most suitable one as a result of trial and error. The load request may be considered as power generated by the fuel cell, for example.

  The load request obtained from the control table in FIG. 5 is set as the reference target generated power. Further, in consideration of the actual behavior of the vehicle, the actually required power is obtained as the target generated power. For example, when it is detected that the road surface is easy to slide, it is better to avoid suddenly increasing the target generated power because the vehicle slips. Therefore, for example, the speed of the vehicle is obtained from the rotational speed of each wheel. Next, from the comparison between the vehicle speed and the value obtained by multiplying the rotational speed of each wheel by the effective diameter of the wheel and the circumference, the friction coefficient of the road surface in contact with each wheel is detected, and the detected value is It is generated by limiting the time change rate of the reference target generated power. Similarly, when it is not desired to perform rapid acceleration, the target generated power may be generated by limiting the rate of time change of the reference target generated power.

  Specifically, in order to obtain the target generated power, for example, when the load increases, the smaller one of (Equation 9) and (Equation 10) may be set as the target generated power. In (Equation 9), ΔP is the maximum increment of the generated power that is allowed to increase every control cycle (cycle for calculating the target generated power), in other words, the limit value of the time change rate.

Target generated power = Target generated power (previous value) + ΔP (Formula 9)
Target generated power = reference target generated power (Formula 10)
In addition, a reference target current that is a target value of the generated current from which the target generated power can be obtained is calculated. For example, a conversion table of generated power and generated current as shown in FIG. 28 may be used. FIG. 28 shows an experiment in which the fuel cell 1 is generated with various generated currents and the generated voltage and generated current are measured. From these experimental results, target generated power (= generated current × generated voltage) is obtained. The current value may be stored in advance in the controller 30 as a conversion table.

  Next, in S102, a system required target air flow rate that is a target value of the air flow rate necessary for the fuel cell 1 to generate the reference target current is determined. At this time, the reference target current may be the current value converted in FIG. 28 based on the reference target generated power in S101. This is because the air flow rate can be sufficiently supplied by using a current signal based on the reference target generated power having a temporal change larger than the target generated power. Hereinafter, a case where the system required target air flow rate is generated by the reference target current based on the target generated power will be described.

  For example, a control table as shown in FIG. 29 may be used for the conversion from the reference target current to the system required target flow rate. In setting the values in the control table of FIG. 29, first, the required flow rate (mass flow rate) of the reactant for generating the reference target current is obtained from the fuel cell chemical reaction equation and the number of cells of the fuel cell. Next, an experiment is performed to generate power at a flow rate obtained by multiplying the necessary flow rate by a stepwise excess rate (eg, 1.4 to 1.8 times, in increments of 0.1). What is necessary is just to obtain | require the flow volume which can fully produce electric power, without generating a voltage fall, and to set it as a control table. Similarly, when the air pressure is changed based on the reference target current, for example, a system required target pressure that is a target value of the air pressure is also set. At this time, it can be easily realized by using the control table as shown in FIG. 30 obtained by the same method as that for obtaining the control table of FIG.

  Next, in S103, a corrected target pressure and a corrected target flow rate are generated based on the system required target pressure and the system required target flow rate generated in S102. If not necessary, this step can be omitted by setting the corrected target pressure as the system required target pressure and the corrected target flow rate as the system required target flow rate. Although details of a method of generating the corrected target pressure and the corrected target flow rate will be described later, the corrected target pressure is brought close to the system required target pressure, and the corrected target flow rate is brought closer to the system required target flow rate. Further, since the corrected target air flow rate is generated to be larger than the system required target air flow rate as the degree of deviation between the corrected target pressure and the system required target force increases, the corrected target pressure is changed to the system required target air pressure. The following performance can be improved.

  Next, in S104, a corrected target current value is generated based on the corrected target pressure, the system required target pressure generated up to S103, the reference target power, and the target generated power. Details regarding this procedure will be described later.

  In S105, the operation amount and the air pressure regulating valve of the compressor 10a are used by using the air pressure value and the air flow value detected by the pressure sensor 6b and the flow sensor 6c, respectively, and the corrected target pressure value and the corrected target flow value calculated in S103. The operation amount of 12 is calculated.

Details of the operation amount generation in S105 in FIG. 24 are the same as those in FIG. 13 described in the reference example . In FIG. 13, a pressure deviation which is a deviation between the air pressure value and the corrected target pressure value is calculated in S401. In S402, a flow rate deviation that is a deviation between the air flow rate value and the corrected target flow rate value is calculated. Either S401 or S402 may be calculated first. In S403, the operation amount of the compressor 10a and the operation amount of the air pressure regulating valve 12 are calculated based on the pressure deviation and the flow rate deviation.

  For example, the operation amount of the air pressure regulating valve 12 may be a target value that is transmitted to a motor that drives the air pressure regulating valve 12 and a microcomputer. The microcomputer that finally drives the air pressure regulating valve 12 includes a detection value of an opening degree sensor (for example, a potentiometer) that measures the opening degree of the air pressure regulating valve 12, and a target value transmitted from the fuel cell system control means of the present invention. May be realized using a known control method such as PID control theory.

  For example, when the compressor command rotational speed is used as the operation amount of the compressor 10a, the command rotational speed is transmitted to the inverter 10b that controls the rotational speed of the compressor 10a. Inverter 10b uses the transmitted compressor command rotation speed as a target value, and applies torque to the motor that drives compressor 10a so that the rotation speed of compressor 10a becomes the compressor command rotation speed. At this time, the torque calculation method can be easily realized by using a known control method such as PID control theory or vector control. Of course, torque applied to the compressor 10a may be calculated instead of the compressor command rotational speed. This case can also be easily realized by using a known control theory such as PID control theory.

  At this time, if it is not necessary to particularly feed back the detection signals of the pressure sensor 6b and the flow rate sensor 6c, feed-forward control which is a known method can be used. In the present invention, the means for calculating the operation amount from the target value may be a known control method. Hereinafter, a case where feedback control is applied will be described. This procedure corresponds to the operation amount generation unit 33a in FIG.

  Next, the procedure for generating the corrected target pressure and the corrected target flow rate in S103 of FIG. 24 will be described in more detail with reference to FIG. As described above, this step can be omitted if the corrected target pressure is set as the system required target pressure and the corrected target flow rate is set as the system required target flow rate if it is not necessary.

  In FIG. 25, first, in S501, the controller 30 calculates a target pressure deviation which is the difference between the system required target pressure and the corrected target pressure. In S502, S503, and S504, the controller 30 generates a flow rate correction value from the target pressure deviation obtained in S501. These steps correspond to the first target correction value generation unit 83 in FIG. 21 and may be calculated by, for example, the program shown in the following [Equation 2].

[Equation 2]
if System Required Target Pressure-Corrected Target Pressure> 0
Flow rate correction value = Kp x (system required target pressure-corrected target pressure)
else
Flow rate correction value = 0
end
Here, Kp is a constant, and the value may be determined while performing a simulation or an experiment using an actual vehicle. If the value of Kp is increased, the corrected target flow rate is increased, and the deviation between the corrected target pressure and the system required target pressure can be reduced. On the other hand, if the value is increased too much, the load on the compressor 10a increases, or the sound from the compressor 10a becomes uncomfortable when the vehicle is accelerated. In view of these, the value of Kp may be determined.

  In S505, the controller 30 generates a corrected target flow rate from the system required target flow rate and the target flow rate correction value. As for the corrected target flow rate, (Equation 11) and (Equation 12) are compared, and the smaller one is set as the final corrected target flow rate.

Corrected target flow rate = system required target flow rate + target flow rate correction value (Equation 11)
Corrected target flow rate = system required target flow rate + Δs (Formula 12)
Here, Δs is the maximum increase in the flow rate per unit calculation time. At this time, Δs may be determined by previously obtaining an increase in the air flow rate that can be followed by the compressor through experiments. Alternatively, Δs may be set to decrease as the outside air temperature increases or as the atmospheric pressure decreases (that is, as the air density in the atmosphere decreases). This is due to the fact that the flow rate that can be supplied by the compressor decreases as the air density decreases.

  In S506, the controller 30 generates a corrected target pressure. In order to generate the corrected target pressure, calculation is performed using (Expression 13) and (Expression 14), and the smaller one may be set as the corrected target pressure. At this time, Δp may be obtained using, for example, a control map as shown in FIG.

Corrected target pressure = system required target pressure (Equation 13)
Corrected target pressure = system required target pressure (previous value) + Δp (Formula 14)
Here, Δp is the maximum increase in pressure per control cycle (cycle for calculating the target generated power), in other words, the time change rate limit value.

The generation of the corrected target pressure can also be obtained using the technique described in the reference example . In FIG. 3, the first target value is the corrected target flow rate, the first target correction unit 41 sets the first target value as the corrected first target value, the desired operation-related amount is according to the reference example , and the second target value is the system request The target pressure may be set.

More specifically, in FIG. 15 of the reference example , Mf = I, a target flow rate correction value may be obtained from ep, and added before the system required target flow rate. Moreover, what is necessary is just to provide the 1st target correction part 41 in the back | latter stage after addition.

  Next, the procedure for obtaining the corrected target current in S104 of FIG. 24 will be described in detail with reference to the flowchart of FIG. The flowchart of FIG. 26 has an inlet for the corrected target current calculation A and an inlet for the corrected target current calculation B. Either of them can be used to determine the corrected target current. In FIG. 26, the same procedure is executed from S603 onward at any entrance.

  First, the corrected target current calculation A will be described. In S601, the difference between the reference target generated power and the target generated power is set as a correction value. By using such a signal as a correction value, the correction value increases during sudden acceleration with a large accelerator opening, and decreases during slow acceleration with a small accelerator opening. This is because the amount of correction increases as the degree of acceleration or depression of the accelerator increases as a result of selection in (Equation 9) and (Equation 10).

  Next, the corrected target current calculation B will be described. In S602, the reference value− (system required target pressure−corrected target pressure) is set as the correction value. Here, the reference value may be a certain fixed value or may change according to time. The correction value in S602 becomes larger as the difference between the system required target pressure and the corrected target pressure is smaller. The reference value is set to such a large value that the total voltage of the fuel cell 1 does not decrease in a transient state while observing the result of instructing the power manager 20 to take out the corrected target current obtained in S610 or S611 in the previous control cycle. That's fine.

  After S603, the corrected target current calculation A and the corrected target current calculation B are the same procedure. In S603, it is determined whether or not the correction value is 0 or more. If the correction value is 0 or more, the process proceeds to S605. If the correction value is a negative value, the process proceeds to step S604, the correction value is set to 0, and the process proceeds to step S605.

  In S605, a delay calculation is performed on the correction value, and the result of the delay calculation is converted into a current correction value ΔI. This delay calculation may be performed by, for example, a first-order delay calculation. If it is not necessary, S605 can be omitted. Also, a constant can be applied to the result of the delay calculation. This constant is a conversion constant for converting the correction value into the dimension of the current. Like the reference value in S602, the power manager 20 is instructed to take out the corrected target current obtained in S610 or S611 in the previous control cycle. While looking at the result, it may be set to a large value such that the total voltage of the fuel cell 1 does not decrease in a transient state.

  In S606, the air pressure of the air electrode of the fuel cell 1 is detected. For example, detection may be performed using the value of the pressure sensor 6b, or a value that predicts the behavior of the air pressure may be used. Alternatively, the same effect can be obtained by using the smaller signal of both.

  In S607, the value of the air pressure obtained in S606 is converted into a current dimension to obtain the generated current Ia. For example, the table of FIG. 7 can be reversed to convert the air pressure to the dimension of the generated power, and the table of FIG. 28 can further convert the generated power to the dimension of the generated current Ia. Any of S606 and S607 and S601 to S605 may be calculated first.

  In S608 to S611, a corrected target current that is a target value commanded to the power manager 20 is generated. In S608, a value obtained by adding the generated current value Ia obtained in S607 and the current correction value ΔI obtained in S605 is set as the maximum extractable current value Imax. In S609, it is determined whether or not the maximum extractable current Imax is equal to or less than the reference target current Is. If the maximum extractable current Imax is equal to or less than the reference target current Is, the process proceeds to S610, and the corrected target current is set to the maximum extractable current value Imax. If the maximum extractable current Imax is larger than the reference target current Is, the process proceeds to S611, and the corrected target current is set as the reference target current Is.

  By adopting such a configuration, the maximum current that can be taken out increases as the vehicle accelerates rapidly or the air pressure is sufficient, and the corrected target current can be increased. Further, if the correction value is increased more than necessary, the maximum current that can be taken out increases, and depending on the reference target current, the corrected target current also becomes excessively large relative to the air pressure, air flow rate, hydrogen pressure, and hydrogen flow rate. As a result, there is a concern that the total voltage of the fuel cell 1 is significantly reduced. If the correction value is too small, the reference target current is constrained by the maximum current that can be taken out, and the response of the generated power to the target generated power is reduced. As a result, the acceleration performance of the vehicle is degraded. For this reason, experiments and the like are repeated to determine how much the correction value should be increased.

  According to the present invention, in the slow acceleration state, the generated current is extracted according to the air pressure to prevent a decrease in the total voltage in the transient state of the fuel cell 1, and in the rapid acceleration state, sufficient to meet the vehicle demand. It becomes possible to take out an electric current. In the rapid acceleration state, since the accelerator is stepped on rapidly, the air pressure can be expected to increase in a short time, so that the total voltage of the fuel cell 1 does not decrease.

  Finally, FIG. 31 shows a time chart when the load suddenly increases according to the present embodiment, and FIG. 32 shows a time chart when the load suddenly increases according to a comparative example when the present invention is not applied. 31 and 32, (a) is a time chart of air flow rate [NL / min], and (b) is a time chart of air pressure [kPa-a]. In the embodiment, since the correction target flow rate is corrected so as to increase as the difference between the system required target pressure and the correction target pressure increases, the rise of the detected value of the air pressure by the pressure sensor is earlier than in the comparative example. As a result, it was confirmed that the acceleration response of the vehicle was increased and the driving performance of the vehicle was improved as a result.

  According to the present embodiment described above, the target value generation unit generates the first target correction value based on the value obtained by subtracting the second target value from the corrected second target value, and uses the first target correction value as the first target correction value. Since the corrected first target value is generated from the result of addition to the one target value, when the corrected second target value deviates from the second target value, correction is performed so that the corrected first target value is increased. Therefore, the time until the corrected first target value matches the first target value or the time until the corrected second target value matches the second target value is shortened, and the load on the fuel cell system is reduced. There is an effect that responsiveness can be improved.

  According to the present embodiment, the corrected second target value is generated so that the time change rate of the corrected second target value increases as the first target value or the first target correction value increases. A corrected second target value commensurate with one target value can be generated, and the corrected first target value and the corrected second target value increase as the first target correction value increases. This has the effect of improving the follow-up performance of the first state quantity and the follow-up performance of the second state quantity to the second target value.

  Further, according to the present embodiment, the target value generating unit sets the first state quantity, the first target value, and the corrected first target value as the air flow rate value, and sets the second state quantity, the second target value, and the corrected second target. The value is an air pressure value. Therefore, the first target correction including a derivative necessary for the corrected second target value (target air pressure) to follow the second target value (system required target air pressure), which cannot be obtained from time to time online. Without calculating the value, the correction value of the target flow rate can be calculated using the calculation result of the corrected target air pressure, the follow-up performance of the corrected first target value to the first target value, and the corrected second There is an effect that the follow-up performance of the target value to the second target value is improved.

  Further, according to the present embodiment, the target value generation unit sets the sum of the first target value and the first target correction value as the corrected first target value, and the corrected second target value increases as the corrected first target value increases. Therefore, as the deviation between the corrected second target value and the second target value decreases, the first target correction value decreases and the deviation between the corrected second target value and the second target value increases. Accordingly, the first target correction value is increased, so that the follow-up of the corrected second target value to the second target value can be accelerated.

  Further, according to the present embodiment, the target value generation unit sets the result of limiting the time change rate of the sum of the first target value and the first target correction value as the corrected first target value, and the corrected first target value is Since the corrected second target value is increased as the value increases, an appropriate amount of reactant can be supplied while avoiding saturation of an operation amount of the reactant supply means, for example, an inverter that controls the compressor motor. effective.

  According to the present embodiment, the first target correction value generation unit generates the first target correction value according to the degree of deviation between the corrected second target value and the second target value, and the value of the first target correction value. Is limited so that the first target value (flow rate) is increased. Therefore, it is necessary to inadvertently reduce the flow rate in order to decrease the second target value (pressure). There is an effect that it can be avoided.

  Further, according to the present embodiment, the target value generation unit includes the target current value generation unit, and the target current value generation unit generates the corrected target current when the corrected second target value is larger or the first target value is generated. The smaller the correction value, the larger the corrected target current with respect to the reference target current. For this reason, it becomes possible to perform power generation commensurate with the air pressure of the fuel cell, and it is possible to avoid power generation in a state where oxygen partial pressure is insufficient.

1 is a system configuration diagram illustrating an overall configuration of a reference example of a fuel cell system according to the present invention. It is a principal part block diagram of the controller (fuel cell system control part) 30 of a reference example . It is a principal part block diagram explaining the structure of the target value production | generation part 32 in a reference example . It is a schematic flowchart explaining the control content of the controller 30 in a reference example . It is an example of the control table which calculates | requires a load request | requirement from an accelerator opening. It is an example of the control table which calculates | requires a system request | requirement target flow volume from a load request | requirement. It is an example of the control table which calculates | requires a system request | requirement target pressure from a load request | requirement. It is an example of the control table which calculates | requires desired air pressure regulation valve opening degree from idle stop time. It is an example of the control table which calculates | requires desired air pressure regulation valve passage flow volume from idle stop time. It is a flowchart explaining the detail of the correction target value production | generation procedure in a reference example . It is a flowchart explaining the detail of the limit value production | generation procedure in a reference example . It is a figure which shows the correction target pressure value with respect to limit value application continuation time. It is a flowchart explaining the detail of the operation amount. FIG. 11 is a block diagram corresponding to S306 in FIG. 10. It is a block diagram of the target value generator in a reference example . It is a modification of the block diagram of the target value generator in a reference example . It is a modification of the block diagram of the target value generator in a reference example . It is a time chart explaining operation | movement of a reference example . It is a time chart explaining operation | movement of a reference example . 1 is a main part configuration diagram of a controller (fuel cell system control unit) 30 according to a first embodiment. It is a principal part block diagram explaining the structure of the target value production | generation part 32a in Example 1. FIG. It is a further detailed principal part block diagram of the target value production | generation part 32a in Example 1. FIG. First target correction value generation unit 83 of the first embodiment and the configuration of a modification of Reference Example a combination of a target value generator 32 of the reference example is a block diagram showing. 3 is a schematic flowchart illustrating the control content of a controller 30 in the first embodiment. 6 is a flowchart illustrating details of a procedure for generating a corrected target value (flow rate, pressure) in the first embodiment. 3 is a flowchart illustrating details of a modified target current generation procedure in the first embodiment. It is an example of the control map which calculates | requires change rate limiting value (DELTA) p from correction target flow volume. It is an example of the control map which calculates | requires generated electric current from generated electric power. It is an example of the control map which calculates | requires a system request | requirement target air flow rate from a reference | standard reference electric current. It is an example of the control map which calculates | requires a system request | requirement target air pressure from a reference | standard reference electric current. (A) a time chart of the air flow rate at the time of sudden increase of the load according to Example 1 [NL / min], is a time chart (b) air pressure at the time of sudden increase of the load according to Example 1 [kPa-a]. (A) Time chart of air flow rate [NL / min] when load is suddenly increased according to comparative example, (b) Time chart of air pressure [kPa-a] when load is suddenly increased according to comparative example.

DESCRIPTION OF SYMBOLS 1 ... Fuel cell, 2 ... Hydrogen tank, 3 ... Hydrogen tank main valve, 4 ... Pressure reducing valve, 5 ... Hydrogen supply valve, 6a, 6b ... Pressure sensor, 6c ... Flow rate sensor, 6d ... Temperature sensor, 6e ... Pressure sensor, DESCRIPTION OF SYMBOLS 7 ... Hydrogen circulation apparatus, 8 ... Purge valve, 9 ... Exhaust hydrogen treatment apparatus, 10a ... Compressor, 10b ... Inverter, 11 ... Humidifier, 12 ... Air pressure regulating valve, 13 ... Cooling water pump, 14, 15 ... Temperature sensor, DESCRIPTION OF SYMBOLS 16 ... Three-way valve, 17 ... Radiator, 18 ... Radiator fan, 19 ... Bypass flow path, 20 ... Power manager, 21a ... Voltage sensor, 21b ... Current sensor, 22 ... Key switch, 23 ... Accelerator opening sensor, 24 ... Hydrogen Circulation path, 30... Controller (fuel cell system control unit), 31... System required target value generation unit, 32... Target value generation unit, 33.

Claims (7)

A fuel cell and a reactant supply means for supplying the reactant to the fuel cell;
A reactant state quantity adjusting means for adjusting a state quantity of the reactant supplied from the reactant supply means to the fuel cell;
Fuel cell system control means for controlling the reactant supply means and the reactant state quantity adjusting means;
In a fuel cell system comprising:
The fuel cell system control means includes system required target value generation means, target value generation means, and operation amount generation means,
The system required target value generation means is configured to respond to a load request for the fuel cell, and a first target value that is a target value of the first state quantity of the reactant and a second state quantity that is different from the first state quantity. Means for generating a second target value which is a target value of the state quantity;
The target value generating means is based on the first target value and the second target value, and a corrected first target value that is a corrected value of the first target value and a corrected second target value that is a corrected value of the second target value. Is a means for generating
The operation amount generation means is a means for calculating the first operation amount and the second operation amount based on the corrected first target value and the corrected second target value,
The target value generating means generates the corrected first target value so that the corrected first target value matches or approximates the first target value, and the corrected second target value becomes the second target value. First target correction value generation for generating the first target correction value according to the degree of divergence between the corrected second target value and the second target value while generating the corrected second target value so as to coincide or approximate Means for generating the corrected first target value based on the first target correction value generated by the first target correction value generation means and the first target value. The target value generating means generates the corrected second target value such that the time change rate of the corrected second target value increases as the first target value or the first target correction value increases. The fuel cell system according to claim 1 , wherein The first state quantity, the first target value, and the modified first target value are flow rates of the reactants, and the second state quantity, the second target value, and the modified second target values are the reactants. The fuel cell system according to claim 1 , wherein the pressure value is as follows. The target value generating means sets the sum of the first target value and the first target correction value as the corrected first target value, and increases the corrected second target value as the corrected first target value increases. The fuel cell system according to claim 1 . The target value generating means further includes a corrected first target value generating means for generating, as the corrected first target value, a value that limits a time change rate of the sum of the first target value and the first target correction value. And
2. The fuel cell system according to claim 1 , wherein the target value generating unit increases the corrected second target value as the corrected first target value increases. The first target correction value generating means is a means for generating a first target correction value according to the degree of deviation between the corrected second target value and the second target value,
2. The fuel cell system according to claim 1 , wherein the first target correction value generation unit generates the first target correction value so as to limit a minimum value of the first target correction value to zero. The target value generation means further includes target current generation means for generating a target current that is a target value of a current to be extracted from the fuel cell system based on the corrected second target value and the first target correction value. ,
2. The fuel cell system according to claim 1 , wherein the target current generating unit increases the target current as the corrected second target value is larger or as the first target correction value is smaller.

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