JP2018156790A - Operation control method and operation control system of fuel cell battery vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operation control method and an operation control system of fuel cell vehicle capable of effectively ejecting impurities such as sulfur component and salt content mixed in the air electrode of the fuel cell together with required air when operating around hot spring or around coast, and capable of reducing cost by reducing the amount of hydrogen consumed.SOLUTION: An operation control system 10 of a fuel cell vehicle including a secondary cell 20, a fuel cell 14, a cooling water flow path 30, and an air conditioning circuit 50, includes a performance deterioration determination section 39 for determining performance deterioration of a fuel cell due to impurities mixed in the fuel cell together with air flowing into the fuel cell, and a recovery operation control section 41 for recovering from performance deterioration by cooling the cooling water flowing through the cooling water flow path by the evaporator of the air conditioning circuit when a determination is made that performance deterioration is occurring based on the determination results from the performance deterioration determination section, thereby cooling the fuel cell, and bringing the fuel cell into over-humidified operation state.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an operation control method and an operation control system of a fuel cell vehicle (FCV) (hereinafter, simply referred to as “fuel cell vehicle”) such as a fuel cell vehicle.

  More specifically, when a fuel cell vehicle is driven, for example, in the vicinity of a hot spring area, a coastal area, etc., the fuel cell is mixed with air necessary for the air electrode of the fuel cell together with impurities such as sulfur components and salt. In order to suppress the degradation of the performance of these, these impurities can be effectively discharged, and the amount of hydrogen consumed and supplied to the fuel electrode (anode), which is the hydrogen electrode, can be reduced and the cost can be reduced. The present invention relates to an operation control method and an operation control system for a simple fuel cell vehicle.

  Conventionally, for example, a fuel cell vehicle equipped with a secondary battery and a fuel cell has been developed and attracted attention in place of an electric vehicle equipped with a secondary battery such as a hybrid car and an internal combustion engine (engine).

As such a fuel cell, a polymer electrolyte fuel cell is used, and it is composed of a fuel cell stack.
That is, the fuel cell stack has a power generation cell having a structure in which an air electrode (cathode) and a fuel electrode (anode) that is a hydrogen electrode are disposed with a solid polymer electrolyte membrane sandwiched between separators. This is configured by stacking a plurality of these.

  The hydrogen gas as the fuel gas is supplied from the hydrogen tank as the fuel gas supply source to the fuel electrode, and the air as the oxidant gas is supplied to the air electrode through the compressor. Has been.

Then, the following reaction occurs, and electric energy is extracted by an electromotive force generated between these electrodes.
Fuel electrode (anode): H ₂ → 2H ⁺ + 2e ⁻
Air electrode (cathode): 1 / 2O ₂ + 2H ⁺ + 2e ⁻ → H ₂ O

  The fuel cell vehicle is equipped with a secondary battery that is charged with electric power generated by the fuel cell and serves as a main power source, and drives the vehicle motor by the electric power stored in the secondary battery. It is configured as follows.

Japanese Patent No. 5807207

  In such a conventional fuel cell vehicle, when the fuel cell vehicle is operated in, for example, a hot spring area, a coastal area, and the like, together with air necessary for the air electrode of the fuel cell, impurities such as sulfur components and salinity May be mixed.

  For this reason, these sulfur components and impurities such as salinity cause the performance degradation of the fuel cell air electrode catalyst and hydrogen electrode catalyst (performance degradation due to poisoning). As a result, the driving performance of the fuel cell vehicle Will drop.

For this reason, Patent Document 1 (Japanese Patent No. 5807207) considers the possibility that sulfur-based substances present or expressed in a stopped fuel cell will poison the electrode when the fuel cell is started. Discloses a method for operating a fuel cell system that supplies a fuel gas that is humidified higher than an oxidant gas and an oxygen gas that is 1% to 5% of the volume of the fuel gas to the fuel electrode when the fuel cell is started. Has been.
Thus, it has been proposed to prevent the electrode from being poisoned by a sulfur-based substance at the time of start-up by making the fuel electrode in a higher humid state than the oxidant electrode.

  However, in the operation method of the fuel cell system of Patent Document 1, only the adjustment method of the components of the fuel gas and the oxygen gas is disclosed at the time of starting the fuel cell. It does not prevent performance deterioration due to poisoning of the fuel cell when driving around the part.

  In addition, in order to suppress the deterioration of the performance of the fuel cell due to impurities such as sulfur components and salinity mixed with the air necessary for the air electrode of the fuel cell, the fuel cell must be It can be considered to be in an excessively humidified operation state.

  However, in order to put the fuel cell in an over-humidified operation state, the amount of hydrogen supplied to the fuel electrode (anode), which is the hydrogen electrode, is increased, and hydrogen is more expensive than electricity. The cost required for this will become high.

  In view of such a current situation, at least one embodiment of the present invention is, for example, a sulfur component or a salt content that is mixed with air necessary for the air electrode of a fuel cell when operating in the vicinity of a hot spring area, the vicinity of a coast, or the like. It is an object of the present invention to provide an operation control method and an operation control system for a fuel cell vehicle that can effectively discharge impurities and the like, reduce the amount of hydrogen consumed, and reduce costs.

  Invented in order to achieve the above-described problems and objects in the prior art, at least one embodiment of the present invention includes a secondary battery serving as a main power source for driving a vehicle driving motor, A fuel cell that constitutes a secondary power source for charging the secondary battery, a cooling water passage including a radiator through which cooling water for cooling the fuel cell flows, and an air conditioner circuit for air conditioning the interior of the vehicle. A fuel cell vehicle operation control method, comprising: a performance degradation determination step for determining a degradation in performance of a fuel cell due to impurities mixed together with air flowing into the fuel cell; and a performance degradation based on a result of the performance degradation determination step. When it is determined that it has occurred, the fuel cell is cooled by cooling the cooling water flowing through the cooling water flow path with an evaporator of the air conditioner circuit, And the charge cell to over-humidification operating condition, characterized in that it comprises a recovery step of recovering the performance degradation.

  In some embodiments, a secondary battery serving as a main power source for driving a vehicle driving motor, a fuel cell constituting a sub-power source for charging the secondary battery, and cooling water for cooling the fuel cell. An operation control system for a fuel cell vehicle, comprising a cooling water flow path including a radiator through which air flows, and an air conditioner circuit for air-conditioning the interior of the vehicle, and fuel caused by impurities mixed with air flowing into the fuel cell A performance degradation determination unit that determines a performance degradation of the battery, and an evaporator of the air conditioner circuit that supplies the cooling water flowing through the cooling water flow path when it is determined that the performance degradation has occurred based on the determination result of the performance degradation determination unit And a recovery operation control unit that cools the fuel cell to bring the fuel cell into an over-humidified operation state and recover the performance degradation.

By comprising in this way, a fuel cell can be cooled by cooling the cooling water which flows through a cooling water flow path with the evaporator of the said air-conditioner circuit.
As a result, the cooling water flowing through the cooling water flow path is further cooled, the fuel cell is cooled below the dew point, and the fuel cell can be brought into an overhumidified operation state.

  As a result, for example, when operating in the vicinity of hot springs, coastal areas, etc., impurities such as sulfur components and salinity may be mixed with the air necessary for the air electrode of the fuel cell, but it is cooled below the dew point. Due to the moisture contained in the air, impurities such as sulfur components and salt can be discharged from the fuel cell.

  Thereby, since the performance deterioration of the fuel cell due to impurities such as sulfur component and salt content can be suppressed, these impurities can be effectively discharged while maintaining the accelerator response.

  In addition, the cooling water flowing through the cooling water flow path is further cooled by heat exchange in the evaporator, and the fuel cell can be cooled below the dew point, so that the fuel cell can be brought into an over-humidified operation state. The amount of hydrogen supplied to the fuel electrode (anode), which is a hydrogen electrode for production, can be reduced, and the cost can be reduced.

  In some embodiments, the fuel cell vehicle is provided with a grill shutter at a front portion of the vehicle, the fuel cell is provided at the rear of the grill shutter, and the recovery operation control unit includes the grill shutter. And opening the fuel cell and starting the fuel cell to control the fuel cell to be in an over-humidified operation state.

  With this configuration, the fuel cell is further cooled by the air introduced from the front portion of the vehicle via the grill shutter, so that the fuel cell is more effectively cooled below the dew point. . Therefore, since the fuel cell can be easily put into an overhumidified operation state, the amount of hydrogen that is supplied to the fuel electrode (anode) that is the hydrogen electrode for moisture generation and consumed is reduced, and the cost is also reduced. be able to.

  Further, in some embodiments, the recovery operation control unit controls to open the grille shutter and start the fuel cell to bring the fuel cell into an excessively humidified operation state during high speed traveling. Features.

  With this configuration, the grill shutter is opened when the traveling air volume is large, such as during high-speed traveling, so that the fuel cell is further cooled by the air introduced from the front of the vehicle. The amount of hydrogen supplied to and consumed by the fuel electrode (anode), which is the hydrogen electrode for moisture generation, because the battery can be cooled more effectively below the dew point and the fuel cell can be put into an over humidified operation state. And the cost can be reduced.

  In some embodiments, the recovery operation control unit opens the grille shutter and starts the fuel cell when the outside air temperature is lower than a predetermined temperature, thereby bringing the fuel cell into an over-humidified operation state. It is characterized by controlling as follows.

  With this configuration, when the outside air temperature is lower than a predetermined temperature (for example, 15 to 20 ° C.), the fuel cell is further effective by opening the grill shutter and the cold air introduced from the front of the vehicle. Since the fuel cell is cooled below the dew point and the fuel cell can be put into an overhumidity operation state, the fuel cell is supplied to the fuel electrode (anode) which is a hydrogen electrode for moisture generation. The amount of hydrogen consumed can be reduced, and the cost can be reduced.

  In some embodiments, the recovery operation control unit is prohibited from being executed when the outside air temperature is 0 ° C. or lower.

  With this configuration, when the outside air temperature is 0 ° C. or lower, the fuel cell is not cooled, and the fuel cell is not put into an overhumidified operation state. This can prevent the water generated from the fuel cell from freezing.

  Further, in some embodiments, the recovery operation control unit cools the fuel cell when it is detected that an SOC value indicating a charging state of the secondary battery exceeds a predetermined value, Control is performed so that the battery is in an excessively humidified operation state.

With this configuration, when it is detected that the SOC value indicating the state of charge of the secondary battery exceeds a predetermined value, the grill shutter is opened and introduced from the front of the vehicle via the grill shutter. Even if the fuel cell is cooled below the dew point by the air that is being used and the fuel cell is in the over-humidified operation state, the SOC does not decrease and the travel is not hindered.
That is, when the fuel cell is cooled, the power generation capability of the fuel cell is reduced, so that there is a risk that the secondary battery will not be fully charged, and there is a risk that the secondary battery will run out of power. For this reason, the fuel cell is cooled when a predetermined SOC is exceeded. Thereby, the performance recovery of the fuel cell can be achieved without deteriorating the charged state of the secondary battery.

  As a result, it is possible to suppress deterioration of the performance of the fuel cell due to impurities such as sulfur components and salt, and to maintain the accelerator response by preventing the deterioration of the charged state of the secondary battery.

According to at least one embodiment of the present invention, the fuel cell can be cooled by cooling the cooling water flowing through the cooling water flow path with the evaporator of the air conditioner circuit.
As a result, the cooling water flowing through the cooling water flow path is further cooled, the fuel cell is cooled below the dew point, and the fuel cell can be brought into an overhumidified operation state.
Therefore, for example, when operating in the vicinity of hot springs, coastal areas, etc., impurities such as sulfur components and salt that are mixed with the air necessary for the air electrode of the fuel cell can be effectively discharged and consumed. The amount of hydrogen produced can be reduced.

It is a block diagram which shows the outline of the driving | running control method and driving | operation control system of the fuel cell vehicle of this invention. It is a flowchart which shows the outline of the driving | running control method and driving | operation control system of the fuel cell vehicle of this invention. It is a flowchart which shows the outline of the driving | running control method and driving | operation control system of the fuel cell vehicle of this invention. It is the elements on larger scale of the block diagram of FIG. 1 which shows the outline of the driving | running control method and driving | operation control system of the fuel cell vehicle of this invention. It is the elements on larger scale of the block diagram of FIG. 1 which shows the outline of the driving | running control method and driving | operation control system of the fuel cell vehicle of this invention. It is the elements on larger scale of the block diagram of FIG. 1 which shows the outline of the driving | running control method and driving | operation control system of the fuel cell vehicle of this invention. It is the elements on larger scale of the block diagram of FIG. 1 which shows the outline of the driving | running control method and driving | operation control system of the fuel cell vehicle of this invention. FIG. 2 is a flowchart similar to FIG. 2 showing an outline of Embodiment 2 of the operation control method and operation control system for a fuel cell vehicle according to the present invention. FIG. 3 is a partially enlarged view of the block diagram of FIG. 1 showing an outline of Embodiment 2 of the operation control method and the operation control system of the fuel cell vehicle according to the present invention. It is a graph which shows the effect by the driving control method and driving control system of a fuel cell vehicle of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.
However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. Absent.

  For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state. On the other hand, the expressions “comprising”, “comprising”, “comprising”, “including”, or “having” one constituent element are not exclusive expressions for excluding the existence of the other constituent elements.

(Embodiment 1)
FIG. 1 shows a fuel cell vehicle 12 equipped with a fuel cell vehicle operation control system 10 of the present invention.
An operation control system 10 for a fuel cell vehicle according to the present invention includes a fuel cell 14 instead of an internal combustion engine of an electric vehicle equipped with a secondary battery such as a hybrid car and an internal combustion engine (engine) in consideration of the environment. The fuel cell vehicle 12 is applied.

  As shown in FIG. 1, the fuel cell vehicle 12 includes a fuel cell 14 that generates power by receiving supply of hydrogen and oxygen. The fuel cell 14 adjusts the voltage via the DC-DC converter 16 and supplies power to the secondary battery 20 that is a main power source for driving the traveling motor 18 of the fuel cell vehicle 12. The secondary battery 20 is configured to be charged.

  The secondary battery 20 constitutes a main power source for driving the traveling motor 18 by being connected to the traveling motor 18 of the fuel cell vehicle via an inverter 22 having a three-phase output.

As such a fuel cell 14, for example, a polymer electrolyte fuel cell is used, and the fuel cell 14 includes a fuel cell stack.
That is, the fuel cell stack has a power generation cell having a structure in which an air electrode (cathode) and a fuel electrode (anode) that is a hydrogen electrode are disposed with a solid polymer electrolyte membrane sandwiched between separators. This is configured by stacking a plurality of these.

  Then, from a hydrogen tank (not shown) that is a fuel gas supply source, hydrogen gas that is a fuel gas is supplied to the fuel electrode, and air that is an oxidant gas is taken in from the outside (atmosphere) and is not shown. It is configured to be supplied to the air electrode via a filter and a compressor.

A reaction as shown below occurs, and electric energy is extracted by an electromotive force generated between these electrodes.
Fuel electrode (anode): H ₂ → 2H ⁺ + 2e ⁻
Air electrode (cathode): 1 / 2O ₂ + 2H ⁺ + 2e ⁻ → H ₂ O

  The fuel cell vehicle 12 is provided with a secondary battery 20 that is charged with power generated by the fuel cell 14 and serves as a main power source. The fuel cell vehicle 12 is powered by the power stored in the secondary battery 20. The traveling motor 18 is driven.

  Further, a part of the air and hydrogen gas respectively supplied to the air electrode and the fuel electrode of the fuel cell 14 are consumed, and unused air and hydrogen gas are passed through an air discharge pipe and a hydrogen discharge pipe (not shown). It is designed to be discharged outside (atmosphere).

As shown in FIG. 1, an openable / closable grill shutter 24 is provided at the front (front) of the fuel cell vehicle 12.
Then, by opening and closing the grill shutter 24, outside air is taken into the drive unit 26 of the fuel cell vehicle 12 provided behind the grill shutter 24, and the fuel cell 14 and the radiator 28 are installed as described later. The flowing cooling water is cooled.

  Further, as shown in FIG. 1, the fuel cell vehicle 12 is provided with a cooling water flow path 30 including a radiator 28 through which cooling water for cooling the fuel cell 14 flows, and the cooling water pump 32 supplies the cooling water. The cooling water channel 30 is configured to circulate.

  As shown in FIG. 1, the fuel cell vehicle 12 is provided with an air conditioner circuit 50 for air conditioning the interior of the vehicle. The air conditioner circuit 50 includes an evaporator 58 that sucks indoor air and exchanges heat with the cooled refrigerant from the refrigerant flow path 52 to send cold air to the passenger compartment.

  The air conditioner circuit 50 includes a known air conditioner circuit 50 that functions as an air conditioner by circulating the air conditioner compressor 54, the condenser (condenser) 56, and the evaporator 58 as indicated by arrows in FIG. Yes.

  In the operation control system 10 of the present invention, as shown in FIG. 1, a branch heat exchange flow path 60 that circulates from the cooling water flow path 30 to the evaporator 58 of the air conditioner circuit 50 is formed.

  That is, the branch heat exchange channel 60 passes through the radiator 28 in the cooling water channel 30, and then the cooling water is switched by the first switching valve 62 and is directed to the evaporator 58. 64.

  Further, the branch heat exchange flow path 60 is provided with a second branch heat exchange flow path 68 in which the cooling water heat-exchanged by the evaporator 58 is switched by the second switching valve 66 and returns to the cooling water flow path 30 again. I have.

  1 shows a state in which the cooling water pump 32 is stopped, the first switching valve 62 and the second switching valve 66 are closed, and the branch heat exchange flow path 60 is closed. Show.

  As shown in FIG. 1, the fuel cell vehicle operation control system 10 includes a control unit 40, and the control unit 40 includes a vehicle ECU 42 for controlling the traveling state of the fuel cell vehicle 12. Yes.

That is, the vehicle ECU 42 is connected to the FC-ECU 38, the motor ECU 44, and the battery ECU 46.
The FC-ECU 38 includes a performance deterioration determination unit 39 that determines the performance deterioration of the fuel cell 14 due to impurities mixed with the air flowing into the fuel cell, in addition to controlling the start (power generation) and stop of the fuel cell 14. Yes.
Further, it has a recovery operation control unit 41 for recovering the performance by controlling the start and stop of the cooling water pump 32, the switching control of the switching valve 36, the opening and closing of the grille shutter 24 based on the determination of the performance deterioration determination unit 39. ing. Note that the recovery operation control unit 41 may be provided separately from the FC-ECU 38.

  Further, the recovery operation control unit 41 controls the cooling water pump 32 to start and stop, the switching control of the first switching valve 62 and the second switching valve 66, and the opening / closing control of the grille shutter 24. And a grill shutter control unit 43 for performing.

  The motor ECU 44 is connected to the inverter 22 and is configured to control the drive of the traveling motor 18 of the fuel cell vehicle 12 by controlling the inverter 22.

  Further, the battery ECU 46 is configured to control charging of the secondary battery 20 and the like. Further, the SOC indicating the state of charge of the secondary battery 20 is detected by the SOC detection means 45, and the information is input to the battery ECU 46 and further input to the vehicle ECU 42.

  By the way, in such a fuel cell vehicle 12, when driving the fuel cell vehicle 12 in, for example, a hot spring area, a coastal area, and the like, together with air necessary for the air electrode of the fuel cell 14, a sulfur component, salinity, and the like. Impurities may be mixed in.

  For this reason, these sulfur components, impurities such as salinity, and the like cause a decrease in the performance of the air electrode catalyst and the hydrogen electrode catalyst of the fuel cell 14 (performance deterioration due to poisoning). Driving performance will be reduced.

  Further, in order to put the fuel cell 14 in the over-humidified operation state, the amount of hydrogen that is supplied to the fuel electrode (anode) that is a hydrogen electrode and consumed is increased, and hydrogen is more expensive than electricity and is recovered. The cost required for processing will increase.

  For this reason, in the fuel cell vehicle 12 of the present invention, the operation control system 10 is controlled by the control unit 40 and is operated as follows.

That is, as shown in the flowchart of FIG. 2, the operation control system 10 is started in step S1.
In step S2, the outside air temperature is referred to by, for example, a temperature sensor (not shown).

  Next, in step S3, the SOC value detected by the SOC detection means 45 is referred. In step S4, it is determined whether or not the outside air temperature exceeds a predetermined temperature (for example, 15 to 20 ° C.) (outside air temperature ≧ predetermined value).

  That is, when the outside air temperature exceeds a predetermined temperature, as will be described later, the cooling water flowing through the cooling water passage 30 is further cooled by heat exchange in the evaporator 58, and the fuel cell 14 is cooled below the dew point. This is because the fuel cell can be brought into an excessively humidified operation state.

  Next, when it is determined in step S4 that the outside air temperature exceeds the predetermined temperature (outside air temperature ≧ predetermined value), the process proceeds to step S5, and in step S5, the SOC value indicating the state of charge of the secondary battery 20 is obtained. It is determined whether or not the predetermined value is exceeded (SOC> predetermined value).

  In this case, the predetermined value of the SOC value is determined by conditions such as the vehicle type, the performance of the traveling motor 18 and the environmental temperature, and is not particularly limited. For example, the SOC value is 20 to 40%. It is a range.

  In step S5, if it is determined that the SOC value indicating the state of charge of the secondary battery 20 exceeds a predetermined value (SOC> predetermined value), the process proceeds to step S6 and the poisoning state of the fuel cell 14 is recovered. It is determined whether it is necessary to do so. Whether or not poisoning recovery is necessary is determined by a performance deterioration determination unit 39 of the FC-ECU 38 as shown in FIG.

  Whether or not this recovery is necessary is determined under the same conditions (under the same conditions of power generation conditions of the fuel cell such as air amount, air temperature, hydrogen gas amount, and hydrogen temperature). And whether or not the current generated voltage is equal (previous voltage≈current voltage).

  Further, the necessity of recovery may be determined by comparing a voltage deviation at a predetermined time with a predetermined determination threshold. Furthermore, the determination may be made based on whether or not the vehicle travels in a hot spring area or a coastal area for a predetermined time or more using an in-vehicle navigation system.

  Furthermore, for example, an impurity sensor that detects impurities such as sulfur components and salt content may be arranged, and it may be determined whether recovery is necessary based on the detection result (impurity concentration) of the impurity sensor.

  If it is determined in step S6 that it is necessary to restore the poisoned state of the fuel cell 14, the process proceeds to step S7. In step S7, as shown in FIG. It is opened and the cooling water is controlled to pass through the evaporator 58.

  That is, as shown by the arrows in FIG. 4, after passing through the radiator 28 in the cooling water flow path 30, the cooling water is switched by the first switching valve 62, and the first branch heat exchange flow path 64 is changed. And introduced into the evaporator 58.

  Then, the evaporator 58 is configured such that the heat-exchanged cooling water is switched by the second switching valve 66 and returns to the cooling water flow path 30 again via the second branch heat exchange flow path 68. ing.

Next, after the cooling water is controlled so as to pass through the evaporator 58 in step S7, the air conditioner is turned on in step S8.
Then, in step S9, the cooling water flowing through the cooling water flow path 30 is further cooled by heat exchange in the evaporator 58, and the “FC low temperature control” operation is started in which the fuel cell 14 is brought into an excessively humidified operation state. Is done.

  Next, it progresses to step S10 and a recovery necessity determination is performed again. That is, in step S10, it is determined whether or not the previous voltage and the current voltage are equal (previous voltage≈current voltage) in the fuel cell 14 under the same conditions.

  In step S10, if it is determined in the fuel cell 14 that the previous voltage is equal to the current voltage (previous voltage≈current voltage), the process proceeds to step S11, where “recovery is necessary OFF”. In step S12, the process returns to step S1.

  On the other hand, if it is determined in step S10 that the previous voltage is not equal to the current voltage in the fuel cell 14, “recovery is required ON” in step S13, and the process proceeds to step S12 and returns to step S1. And repeated.

  On the other hand, if it is determined in step S5 that the SOC value indicating the state of charge of the secondary battery 20 does not exceed the predetermined value (the SOC value is equal to or less than the predetermined value), the process proceeds to step S14 and normal control is performed. (FC temperature constant control).

That is, in the normal control (FC temperature constant control) in step S14, the branch heat exchange flow path 60 is closed and the cooling water is controlled not to pass through the evaporator 58, as shown in FIG. As shown in FIG. 5, the first switching valve 62 and the second switching valve 66 are both closed.
As described above, when the SOC is equal to or lower than the predetermined value, if the FC low temperature control is performed as in step S9, the power generation capacity of the fuel cell 14 is reduced, and therefore the secondary battery 20 may not be sufficiently charged. Since there is a risk that the secondary battery 20 will run out of power, FC low temperature control is not executed below a predetermined SOC.

  Next, after step S <b> 14, the process proceeds to step S <b> 10, and recovery necessity determination is performed as described above. That is, in step S10, it is determined whether or not the previous voltage and the current voltage are equal (previous voltage≈current voltage) in the fuel cell 14 under the same conditions.

  On the other hand, if it is determined in step S6 that it is not necessary to restore the charged state of the secondary battery 20, the process proceeds to step S14 as described above, and normal control is performed (FC temperature constant control).

On the other hand, when it is determined in step S4 that the outside air temperature does not exceed the predetermined temperature (outside air temperature <predetermined value), the process proceeds to step S15 as shown in the flowchart of FIG.
In step S15, it is determined whether or not the outside air temperature exceeds 0 ° C. (outside air temperature> 0 ° C.).

That is, when the outside air temperature is 0 ° C. or lower, the fuel cell 14 is not cooled, and control is performed so that the fuel cell 14 is not in an excessively humidified operation state.
This is because when the outside air temperature is 0 ° C. or lower, the fuel cell 14 is not cooled and the fuel cell 14 is not put into an excessively humidified operation state to prevent the cooling water, the fuel cell 14 and the like from being frozen.

  Next, when it is determined in step S15 that the outside air temperature exceeds 0 ° C., the process proceeds to step S16, and in step S16, it is necessary to recover the charged state of the fuel cell 14 as in step S6. It is determined whether or not.

  If it is determined in step S16 that it is necessary to restore the poisoned state of the fuel cell 14, the process proceeds to step S17, and the grill shutter 24 is opened in step S17 as shown in FIG.

  Next, in step S18, the fuel cell 14 is started (power generation), and the fuel cell 14 is cooled below the dew point by the air introduced from the front of the fuel cell vehicle 12 via the grill shutter 24. Then, the “FC low temperature control” operation is started in which the fuel cell 14 is brought into the overhumidified operation state.

  Next, it progresses to step S19 and recovery necessity judgment is performed. That is, in step S19, it is determined whether or not the previous voltage and the current voltage are equal in the fuel cell 14 under the same conditions (previous voltage≈current voltage).

  If it is determined in step S19 that the previous voltage and the current voltage are equal in the fuel cell 14 (previous voltage≈current voltage), the process proceeds to step S20, where “recovery is required OFF”. In step S12 of FIG. 2, the process returns to step S1.

  On the other hand, if it is determined in step S19 that the previous voltage and the current voltage are not equal in the fuel cell 14, "recovery is required ON" in step S21, and the process proceeds to step S12 in FIG. Return to step S1.

  On the other hand, if it is determined in step S15 that the outside air temperature does not exceed 0 ° C. (the outside air temperature is 0 ° C. or less), the process proceeds to step S22, and the grill shutter 24 is closed as shown in FIG. Thus, normal control is performed (FC temperature constant control).

  Next, after step S22, the process proceeds to step S19, and the necessity of recovery is determined in the same manner as described above. That is, in step S19, it is determined whether or not the previous voltage and the current voltage are equal in the fuel cell 14 under the same conditions (previous voltage≈current voltage).

  If it is determined in step S16 that it is not necessary to recover the poisoned state of the fuel cell 14, the process proceeds to step S22, and normal control is performed with the grill shutter 24 closed (FC temperature). Constant control).

  By configuring in this way, a branch heat exchange channel 60 that circulates through the evaporator 58 of the air conditioner circuit 50 is formed from the coolant channel 30, and the coolant that flows through the coolant channel 30 by the branch heat exchange channel 60. The fuel cell 14 can be cooled by performing the heat exchange and cooling.

  As a result, the cooling water flowing through the cooling water flow path 30 is further cooled, and the fuel cell 14 is cooled below the dew point, so that the fuel cell 14 can be brought into an overhumidified operation state.

  As a result, for example, when operating in the vicinity of hot springs, coastal areas, etc., impurities such as sulfur components and salinity may be mixed with the air necessary for the air electrode of the fuel cell, but it is cooled below the dew point. Due to the moisture contained in the air, impurities such as sulfur components and salt can be discharged from the fuel cell 14.

  Thereby, while being able to suppress the performance degradation of the fuel cell 14 by impurities, such as a sulfur component and salt content, these impurities can be discharged | emitted effectively, maintaining an accelerator response.

  In addition, the cooling water flowing through the cooling water flow path 30 is further cooled by heat exchange in the evaporator 58, and the fuel cell 14 is cooled below the dew point, so that the fuel cell 14 is brought into an excessively humidified operation state. Therefore, the amount of hydrogen supplied to the fuel electrode (anode) that is a hydrogen electrode and consumed is reduced, and the cost can be reduced.

  Further, when the outside air temperature is lower than a predetermined temperature, the grill shutter 24 is opened and the fuel cell 14 is started to control the fuel cell 14 to be in an excessively humidified operation state.

  With this configuration, when the outside air temperature is lower than a predetermined temperature (for example, 15 to 20 ° C.), the grill shutter 24 is opened and the fuel is cooled by the cold air introduced from the front portion of the fuel cell vehicle 12. The battery 14 is further cooled, and the fuel cell 14 is cooled below the dew point, so that the fuel cell 14 can be brought into an excessively humidified operation state. Therefore, the fuel cell 14 is supplied to the fuel electrode (anode) that is a hydrogen electrode, The amount of hydrogen consumed can be reduced, and the cost can be reduced.

  Further, when the outside air temperature is 0 ° C. or lower, the fuel cell 14 is not cooled, and the fuel cell 14 is controlled not to be in an excessively humidified operation state.

  With this configuration, when the outside air temperature is 0 ° C. or lower, the fuel cell 14 is not cooled, and the fuel cell 14 is not put into an excessively humidified operation state. This can prevent the water generated from the fuel cell from freezing.

FIG. 10 is a graph showing the effect of the driving control method and driving control system for a fuel cell vehicle according to the present invention.
That is, the conditions necessary for securing the same amount of condensed water are shown. As shown in FIGS. 10A and 10B, when the FC temperature (the temperature of the fuel cell 14) decreases, the amount of hydrogen consumed decreases in proportion to the saturated vapor pressure of water.

  On the other hand, as shown in FIGS. 10A and 10C, when the FC temperature (the temperature of the fuel cell 14) is lowered using the evaporator 58 of the air conditioner circuit 50, the power consumption increases. Become.

  However, since “power consumption × unit price of power” is lower than “hydrogen consumption × unit price of hydrogen”, the evaporator 58 of the air conditioner circuit 50 is used to lower the FC temperature (temperature of the fuel cell 14). In the “FC low temperature control” operation, the overhumidification operation can be performed at a lower cost, and the performance of the fuel cell 14 can be recovered.

(Embodiment 2)
FIG. 8 is a flowchart similar to FIG. 2 showing an outline of the operation control method and operation control system for a fuel cell vehicle according to the present invention, and FIG. 9 shows another operation control method and operation control system for a fuel cell vehicle according to the present invention. FIG. 3 is a partial enlarged view of the block diagram of FIG. 1 showing an outline of a second embodiment.

  The fuel cell vehicle operation control system 11 of this embodiment has basically the same configuration as that of the operation control system 10 of the first embodiment shown in FIGS. 1 to 7, and the same constituent members have the same components. Reference numerals are assigned and detailed description thereof is omitted.

The operation control system 11 of the fuel cell vehicle 12 according to the second embodiment is operated as follows.
The flowchart in FIG. 8 is basically the same steps as the flowchart in FIG. 2, and therefore, the same steps are denoted by the same reference numerals, and detailed description thereof is omitted. Further, since the steps in the flowchart of FIG. 3 are the same, the illustration is omitted.

  In the operation control system 11 of the second embodiment, when it is determined in step S6 of FIG. 8 that it is necessary to recover the poisoned state of the fuel cell 14, the process proceeds to step S30 and is shown in FIG. Thus, in step S30, the grill shutter 24 is controlled to be opened.

  In step S30, after the grille shutter 24 is opened, the process proceeds to step S7 as in the first embodiment. In step S7, as shown in FIG. 9, the branch heat exchange channel 60 is opened, The cooling water is controlled to pass through the evaporator 58.

  With this configuration, the grill shutter 24 is opened, and the fuel cell 14 is started to control the fuel cell 14 to be in an excessively humidified operation state.

  Accordingly, the fuel cell 14 is cooled below the dew point by the air introduced from the front of the fuel cell vehicle 12 via the grill shutter 24 by opening the grill shutter 24 and starting (generating power) the fuel cell 14. Thus, the fuel cell 14 can be brought into an overhumidified operation state.

  In addition, the fuel cell 14 is further cooled by the air introduced from the front portion of the fuel cell vehicle 12 via the grill shutter 24, and the fuel cell 14 is cooled below the dew point. Since it can be in an excessively humidified operation state, the amount of hydrogen supplied to the fuel electrode (anode), which is a hydrogen electrode for moisture generation, can be reduced, and the cost can also be reduced.

  In this case, when the grille shutter 24 is opened in step S30, the grille shutter 24 is opened and the fuel cell 14 is started and the fuel cell 14 is started when, for example, the airflow detection sensor (not shown) has a large running airflow. It is desirable to control the battery 14 to be in an overhumidified operation state.

  With this configuration, the grille shutter 24 is opened when the travel air volume is large, for example, during high-speed travel, so that the fuel cell 14 is further cooled by the air introduced from the front of the fuel cell vehicle 12. As a result, the fuel cell 14 is cooled below the dew point, and the fuel cell 14 can be brought into an excessively humidified operation state, so that the hydrogen supplied to the fuel electrode (anode), which is a hydrogen electrode, is consumed. The amount can be reduced and the cost can be reduced.

Further, when it is detected that the SOC value indicating the charged state of the secondary battery 20 exceeds a predetermined value, the fuel cell 14 is cooled to control the fuel cell 14 to be in an excessively humidified operation state. Therefore, poisoning of the fuel cell 14 can be achieved without deteriorating the charged state of the secondary battery 20.
That is, when FC low-temperature control is performed, the power generation capacity of the fuel cell 14 is reduced, so there is a risk that the secondary battery 20 will not be fully charged, and there is a risk that the secondary battery 20 will be in an out-of-charge state. For this reason, FC low temperature control is executed when a predetermined SOC is exceeded.

  As described above, according to the second embodiment, since the fuel cell 14 is further cooled by the air introduced from the front portion of the vehicle via the grill shutter 24, the fuel cell 14 is more effectively Cool below dew point. Therefore, since the fuel cell 14 can be easily put into an overhumidified operation state, the amount of hydrogen that is supplied to the fuel electrode (anode) that is a hydrogen electrode for moisture generation and consumed is reduced, and the cost is also reduced. can do.

  According to at least one embodiment of the present invention, for example, when operating in the vicinity of a hot spring area, the vicinity of a coast, etc., impurities such as sulfur components and salinity mixed in with the air necessary for the air electrode of the fuel cell are effective. In addition, the amount of hydrogen consumed can be reduced and the cost can be reduced. Therefore, the fuel cell vehicle is suitable for use in an operation control method and an operation control system of a fuel cell vehicle.

DESCRIPTION OF SYMBOLS 10, 11 Operation control system 12 Fuel cell vehicle 14 Fuel cell 16 DC-DC converter 18 Driving motor 20 Secondary battery 22 Inverter 24 Grill shutter 26 Drive part 28 Radiator 30 Cooling water flow path 32 Cooling water pump 38 FC-ECU
39 Performance Degradation Determination Unit 40 Control Unit 41 Recovery Operation Control Unit 42 Vehicle ECU
43 Grill shutter control unit 44 Motor ECU
45 SOC detection means 46 Battery ECU
47 Cooling water control unit 50 Air conditioner circuit 52 Refrigerant channel 54 Air conditioner compressor 58 Evaporator 60 Branch heat exchange channel 62 First switching valve 64 First branch heat exchange channel 66 Second switching valve 68 Second branch heat Exchange flow path

Claims (7)

A secondary battery serving as a main power source for driving a vehicle driving motor;
A fuel cell constituting a secondary power source for charging the secondary battery;
A cooling water flow path including a radiator through which cooling water for cooling the fuel cell flows;
An air conditioner circuit for air conditioning the interior of the vehicle;
A fuel cell vehicle operation control method comprising:
A performance degradation determination step for determining performance degradation of the fuel cell due to impurities mixed in with air flowing into the fuel cell;
Based on the result of the performance degradation determination step, when it is determined that performance degradation has occurred, the cooling water flowing through the cooling water flow path is cooled by an evaporator of the air conditioner circuit, thereby cooling the fuel cell. And a recovery step of recovering the performance degradation by putting the fuel cell in an excessively humidified operation state. A secondary battery serving as a main power source for driving a vehicle driving motor;
A fuel cell constituting a secondary power source for charging the secondary battery;
A cooling water flow path including a radiator through which cooling water for cooling the fuel cell flows;
An air conditioner circuit for air conditioning the interior of the vehicle;
An operation control system for a fuel cell vehicle comprising:
A performance degradation determination unit that determines performance degradation of the fuel cell due to impurities mixed in with air flowing into the fuel cell;
When it is determined that a performance degradation has occurred based on the judgment result of the performance degradation judgment unit, the fuel cell is cooled by cooling the cooling water flowing through the cooling water flow path with an evaporator of the air conditioner circuit. An operation control system for a fuel cell vehicle, comprising: a recovery operation control unit configured to restore the performance degradation by putting the fuel cell in an overhumidity operation state. The fuel cell vehicle is provided with a grill shutter at the front of the vehicle, and the fuel cell is provided behind the grill shutter,
3. The fuel cell vehicle according to claim 2, wherein the recovery operation control unit controls the fuel cell to be in an excessively humidified operation state by opening the grill shutter and starting the fuel cell. Operation control system.   4. The control according to claim 3, wherein the recovery operation control unit controls to open the grille shutter and start a fuel cell to put the fuel cell in an over-humidified operation state when traveling at high speed. Operation control system for fuel cell vehicles.   The recovery operation control unit controls to open the grille shutter and start the fuel cell to place the fuel cell in an excessively humidified operation state when the outside air temperature is lower than a predetermined temperature. The operation control system of the fuel cell vehicle according to claim 3.   6. The operation control system for a fuel cell vehicle according to claim 2, wherein execution of the recovery operation control unit is prohibited when the outside air temperature is 0 ° C. or lower.   When the SOC value indicating the state of charge of the secondary battery is detected to exceed a predetermined value, the recovery operation control unit cools the fuel cell and puts the fuel cell into an over-humidified operation state. The operation control system for a fuel cell vehicle according to any one of claims 2 to 6, wherein

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