JP5558909B2 - Power supply system - Google Patents

Description

  The present invention relates to a power supply system that supplies power to an external load (motor, compressor, etc.).

  In recent years, development of fuel cell vehicles, hybrid vehicles and the like has been promoted from the viewpoint of environmental protection. This fuel cell vehicle includes a fuel cell (power generation device) and a battery (power storage device), and the hybrid vehicle includes a power generation device and a battery. Note that the power generation apparatus of the hybrid vehicle includes an engine (internal combustion engine) that is driven by burning fuel and a generator that is operated by the driving force of the engine.

Here, the fuel cell has a temperature (optimum power generation temperature) that can be optimally generated in accordance with the type of the fuel cell. For example, the optimal power generation temperature of a polymer electrolyte fuel cell is 80-90 ° C.
The battery also has a temperature (optimum charge / discharge temperature) that can be optimally charged / discharged according to the type (lithium ion type, nickel hydrogen type, etc.). Furthermore, the engine also has a temperature at which it can be driven optimally (optimum driving temperature).

  Therefore, when starting a fuel cell vehicle, a hybrid vehicle, etc., especially when starting in a low temperature environment such as 0 ° C. or lower, the fuel cell, battery, engine, etc. are warmed up to their optimum temperature in a short time, that is, warmed up. This is very important.

Therefore, for example, in Patent Document 1, in a fuel cell system including a fuel cell and a battery, a fuel cell heater using the battery as a power source and a battery heater are provided, and the fuel cell and the battery are warmed by these heaters. That is, a technique for warming up has been proposed.
Patent Document 2 discloses that in a fuel cell system including a fuel cell, a battery, and an auxiliary device (compressor or the like) that consumes output, the fuel cell is warmed up by generating power, and the battery is discharged. Technologies for warming up the battery have been proposed.

JP 2004-31218 A JP 2004-281219 A

However, in Patent Document 1, since the heater for the fuel cell and the heater for the battery are provided, the system configuration becomes complicated, the number of parts increases, and power (energy) is consumed by the heater. .
In Patent Document 2, the fuel cell and the battery are warmed up. However, in order to shorten the time required for warming up as much as possible, further technical improvement is desired.

  Accordingly, an object of the present invention is to provide a power supply system that warms up a power storage device or a power generation device that should be warmed up preferentially while simplifying the system configuration.

As means for solving the above problems, the present invention provides a power storage device capable of charging and discharging power, a power generation device capable of charging power to the power storage device, and a first temperature sensor for detecting a temperature of the power storage device. A second temperature sensor for detecting the temperature of the power generation device, a control means for controlling charge / discharge of the power storage device and power generation of the power generation device, and a start switch that is turned on when starting the system, The control means detects the ON signal of the start switch and starts the system, based on the temperature of the power storage device and the temperature of the power generation device when the start switch is ON, based on the temperature of the power storage device and the power generation device either one in preference to the other determines what to warm up, preferentially the one warm-up should be warmed up, the power supply cis, characterized in that to promote than the other warm-up of the It is a non.

  According to such a power supply system, when the system is started, the control unit determines that one of the power storage device and the power generation device is based on the temperature of the power storage device and the temperature of the power generation device when the start switch is ON. It is determined whether to warm up in priority, and one of the warming up is warmed up according to the determination result. Accordingly, the power storage device or the power generation device that should be preferentially warmed up can be warmed up early.

Here, with respect to the power storage device, warming-up proceeds by controlling charging / discharging, for example, by increasing charging power or discharging power. In addition, the power generation apparatus is warmed up by controlling the power generation, for example, by increasing the generated power.
That is, since a dedicated heating means such as an electric heater is not provided, the system configuration is simple. Therefore, it can be easily mounted on a moving body such as a fuel cell vehicle or a hybrid vehicle.

In the power supply system, the control means may promote the warm-up of the other when the warm-up of the other is not completed after the warm-up of the one is completed. preferable.

  According to such an electric power supply system, when the warm-up of the other is not completed after the warm-up of the one warmed up preferentially, the other can be warmed up. That is, warming up of both the power storage device and the power generation device can be completed.

  In the power supply system, it is preferable that the control unit determines that the power storage device is preferentially warmed up when the temperature of the power storage device at the time of ON is equal to or lower than a predetermined power storage device temperature.

  According to such a power supply system, the control unit determines that the power storage device having a temperature equal to or lower than the predetermined power storage device temperature is preferentially warmed up when the control unit is turned on. Can be determined appropriately.

  Further, in the power supply system, the control unit compares the output recovery speed of the power storage device at the temperature at the time of ON with the output recovery speed of the power generation device at the temperature at the time of ON, so that the power storage device and the power generation It is preferable to preferentially warm up the device with the higher output recovery speed among the devices.

  According to such a power supply system, the control means compares the output recovery rates of the power storage device and the power generation device at the temperature at the time of ON, and preferentially warms up the higher output recovery rate. Since the determination is made, it is possible to appropriately determine which of the power storage device and the power generation device is preferentially warmed up.

  Further, in the power supply system, the control means includes a first difference between a maximum output of the power storage device at a temperature at ON time and a maximum output of the power storage device at a normal time, and the power storage device at a temperature at ON time. And comparing the second difference between the maximum output of the power storage device and the maximum output of the power storage device in a normal state, and determining to warm up with priority being given to the larger of the first difference and the second difference. Is preferred.

  According to such a power supply system, the control means warms up with priority given to the larger difference between the first difference and the second difference, that is, giving priority to the larger recovery margin. Since the determination is made, it is possible to appropriately determine which of the power storage device and the power generation device is preferentially warmed up.

In the power supply system, it is preferable that the control unit increases charging power or discharging power with respect to a normal time when promoting warm-up of the power storage device.

  According to such a power supply system, when the power storage device is warmed up, the control means increases the charging power or the discharge power more than normal time (non-warm-up time). it can.

In the power supply system, it is preferable that the control unit increases the output with respect to the normal time when the warm-up of the power generator is promoted .

  According to such a power supply system, when the power generator is warmed up, the control means increases the output (in the embodiment described later, the generated power of the fuel cell or the generator, the output of the engine) compared to the normal time. Therefore, the power generator can be warmed up early.

  ADVANTAGE OF THE INVENTION According to this invention, the electric power supply system which warms up quickly the electrical storage apparatus or electric power generating apparatus which should be warmed up preferentially can be provided, making a system structure simple.

It is a figure which shows the structure of the fuel cell system which concerns on 1st Embodiment. It is a flowchart which shows operation | movement of the fuel cell system which concerns on 1st Embodiment. It is a flowchart which shows the warming-up priority determination process which concerns on 1st Embodiment. It is a time chart which shows the operation example of the fuel cell system which concerns on 1st Embodiment. It is a time chart which shows the operation example of the fuel cell system which concerns on 1st Embodiment. It is a flowchart which shows the warming-up priority determination process which concerns on 2nd Embodiment. It is a map which shows the relationship between the temperature of a battery and a fuel cell, and output recovery speed. It is a flowchart which shows the warming-up priority determination process which concerns on 3rd Embodiment. It is a map which shows the relationship between the temperature and the maximum output of a battery and a fuel cell. It is a figure which shows the structure of the hybrid system which concerns on 4th Embodiment. It is a map which shows the relationship between the temperature of a battery and a generator (engine), and output recovery speed. It is a map which shows the relationship between the temperature of a battery and a generator (engine), and maximum output.

<< First Embodiment >>
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

≪Configuration of fuel cell system≫
A fuel cell system 1 (power supply system) according to the first embodiment shown in FIG. 1 is mounted on a fuel cell vehicle (moving body) (not shown). The fuel cell system 1 includes a fuel cell stack 10 (power generation device), an anode system that supplies and discharges hydrogen (fuel gas and reactive gas) to and from the anode of the fuel cell stack 10, and a cathode of the fuel cell stack 10 A cathode system that supplies and discharges oxygen-containing air (oxidant gas, reaction gas), a power consumption system that consumes the power of the fuel cell stack 10, and an ECU 60 (Electronic Control Unit) that electronically controls them It is equipped with.

<Fuel cell stack>
The fuel cell stack 10 is a stack formed by stacking a plurality of (eg, 200 to 400) solid polymer type single cells, and the plurality of single cells are connected in series. The single cell includes an MEA (Membrane Electrode Assembly) and two conductive separators sandwiching the MEA. The MEA includes an electrolyte membrane (solid polymer membrane) made of a monovalent cation exchange membrane or the like, and an anode and a cathode (electrode) that sandwich the membrane.

The anode and the cathode include a porous body having conductivity such as carbon paper, and a catalyst (Pt, Ru, etc.) supported on the anode and causing an electrode reaction in the anode and the cathode.
Each separator is formed with a groove for supplying hydrogen or air to the entire surface of each MEA, and through holes for supplying and discharging hydrogen or air to all single cells. These grooves and through holes serve as anodes. It functions as a channel 11 (fuel gas channel) and a cathode channel 12 (oxidant gas channel).

When hydrogen is supplied to each anode via the anode flow path 11, the electrode reaction of Formula (1) occurs, and when air is supplied to each cathode via the cathode flow path 12, Formula (2) Thus, a potential difference (OCV (Open Circuit Voltage), open circuit voltage) is generated in each single cell. Next, the fuel cell stack 10 is electrically connected to an external load such as a motor 44 described later, and when the current is taken out, the fuel cell stack 10 generates power.
2H ₂ → 4H ⁺ + 4e ⁻ (1)
O ₂ + 4H ⁺ + 4e ⁻ → 2H ₂ O (2)

  Each separator is formed with grooves and through-holes through which the refrigerant flows in order to cool the single cell appropriately, and these grooves and through-holes function as the refrigerant flow path 13 of the fuel cell stack 10. ing.

  A pipe 13 a is connected to the inlet of the refrigerant flow path 13 so that a refrigerant from a radiator (not shown) flows into the refrigerant flow path 13 through the pipe 13 a. On the other hand, a pipe 13b is connected to the outlet of the refrigerant flow path 13, and the refrigerant from the refrigerant flow path 13 is directed to the radiator through the pipe 13b. That is, the refrigerant is configured to circulate between the refrigerant flow path 13 and the radiator. Incidentally, a refrigerant pump (not shown) that pumps the refrigerant is provided in a circulation circuit in which the refrigerant circulates.

A temperature sensor 14 (second temperature sensor) is attached to the pipe 13b. The temperature sensor 14 detects the temperature of the refrigerant discharged from the refrigerant flow path 13 as the temperature of the fuel cell stack 10 and outputs the detected temperature to the ECU 60.
However, the position of the temperature sensor 14 for detecting the temperature of the fuel cell stack 10 is not limited to this. For example, the temperature sensor 14 may be attached to the pipe 23b and the pipe 32a, or may be provided in the fuel cell stack 10. .

<Anode system>
The anode system includes a hydrogen tank 21, a normally closed shut-off valve 22, an ejector 23, and a normally closed purge valve 24.
The hydrogen tank 21 is connected to the inlet of the anode channel 11 through a pipe 21a, a shutoff valve 22, a pipe 22a, an ejector 23, and a pipe 23a. When the shutoff valve 22 is opened in accordance with a command from the ECU 60, hydrogen is supplied from the hydrogen tank 21 to the anode flow path 11 through the shutoff valve 22 and the like. The pipe 22a is provided with a pressure reducing valve (not shown) for reducing the hydrogen pressure to a predetermined pressure.

  The outlet of the anode channel 11 is connected to the intake port of the ejector 23 via the pipe 23b. Then, the anode offgas (fuel offgas) containing unconsumed hydrogen discharged from the anode flow path 11 is returned to the ejector 23 through the pipe 23b and then resupplied to the anode flow path 11. ing. That is, the pipe 23b constitutes a hydrogen circulation line for circulating hydrogen.

The middle of the pipe 23b is connected to the diluter 33 via the pipe 24a, the purge valve 24, and the pipe 24b.
The purge valve 24 is opened by the ECU 60 when discharging (purging) impurities (water vapor, nitrogen, etc.) contained in the circulating anode off-gas during power generation (system operation) of the fuel cell stack 10.
For example, the ECU 60 determines that the impurities need to be discharged when the voltage (cell voltage) of the single cells constituting the fuel cell stack 10 is equal to or lower than a predetermined cell voltage, and opens the purge valve 24. It has become. The cell voltage is detected, for example, via a voltage sensor (cell voltage monitor) that detects the voltage of a single cell.

<Cathode system>
The cathode system includes a compressor 31, a back pressure valve 32, and a diluter 33.
The compressor 31 is connected to the inlet of the cathode channel 12 via a pipe 31a. When the compressor 31 operates according to a command from the ECU 60, the compressor 31 takes in oxygen-containing air and supplies the air to the cathode channel 12 via the pipe 31a.

  In addition, the humidifier (not shown) is provided so that the piping 31a and the piping 32a may be straddled. This humidifier incorporates a plurality of hollow fiber membranes that are permeable to moisture, and through this hollow fiber membrane, the air that flows toward the cathode channel 12 and the humid cathode offgas discharged from the cathode channel 12 Moisture exchange is performed between them to humidify the air toward the cathode channel 12.

The outlet of the cathode channel 12 is connected to the diluter 33 via a pipe 32a, a back pressure valve 32, and a pipe 32b. The cathode off-gas discharged from the cathode channel 12 is guided to the diluter 33 through the pipe 32a and the like.
The back pressure valve 32 is composed of, for example, a butterfly valve, and its opening degree is controlled by the ECU 60 to control the pressure of air in the cathode flow path 12.

  The diluter 33 is a container that mixes the anode off-gas from the purge valve 24 and the cathode off-gas (dilution gas) from the pipe 32b, and dilutes the hydrogen in the anode off-gas with the cathode off-gas. It has space. The diluted gas is discharged out of the vehicle through the pipe 33a.

<Power consumption system>
The power consumption system includes a battery 41 (power storage device), a temperature sensor 42 (first temperature sensor), a power controller 43, and a motor 44. The battery 41 is connected to the output terminal of the fuel cell stack 10 via a power controller 43, and the motor 44 is connected to the power controller 43 via a PDU 45 (Power Drive Unit). That is, the battery 41 and the motor 44 are connected to the fuel cell stack 10 in parallel.

The battery 41 is a power storage device that charges the generated power of the fuel cell stack 10 and / or the regenerative power from the motor 44 and discharges the internal power. Such a battery 41 is constituted by an assembled battery formed by assembling a plurality of single cells such as lithium ion type and nickel hydride type in series.
In addition, the battery 41 is placed in a situation where it is difficult to warm up the fuel cell stack 10 to which high-pressure, high-temperature air or the like is supplied, that is, it is difficult to raise the temperature.

  The temperature sensor 42 is a sensor that detects the temperature of the battery 41, and is attached, for example, in a battery case that houses the plurality of single cells. The temperature sensor 42 detects the temperature of the battery 41 and outputs it to the ECU 60.

The power controller 43 includes a power generation control function for controlling power generation of the fuel cell stack 10 and a charge / discharge control function for controlling charge / discharge of the battery 41 in accordance with a command from the ECU 60. That is, the power controller 43 supplies the fuel cell stack 10 and the battery 41, which are power supply sources, to supply power corresponding to the accelerator opening to the PDU 45 (motor 44). (Charging power) is controlled.
Note that such a power controller 43 includes a DC / DC converter having a step-up / step-down function, a DC / DC chopper, and the like.

  The motor 44 generates a driving force for running the fuel cell vehicle using electric power. The motor 44 generates regenerative power when the fuel cell vehicle decelerates, and supplies it to the power controller 43 via the PDU 45.

  The PDU 45 is an inverter that converts DC power from the power controller 43 into three-phase AC power and outputs it to the motor 44 in accordance with a command from the ECU 60. The PDU 45 converts the regenerative power from the motor 44 into DC power and outputs it to the power controller 43 when the fuel cell vehicle is decelerated.

  An output detector 46 is provided between the battery 41 and the power controller 43. The output detector 46 detects the output (voltage value, current value) of the battery 41 and outputs it to the ECU 60. Thus, the ECU 60 can calculate the output recovery speed (kW / min) and SOC (State Of Charge) of the battery 41 based on the voltage value and the current value.

  Further, an output detector 47 is provided between the fuel cell stack 10 and the power controller 43. The output detector 47 detects the output (voltage value, current value) of the fuel cell stack 10 and outputs it to the ECU 60. As a result, the ECU 60 can calculate the output recovery speed (kW / min) and the power generation performance (IV performance) of the fuel cell stack 10.

  Furthermore, an auxiliary machine 48 such as a compressor 31 and a refrigerant pump for pumping refrigerant is connected to the power controller 43. The power from the power controller 43 is supplied to the auxiliary machine 48.

<Other equipment>
The IG 51 is a start switch of the fuel cell system 1 (fuel cell vehicle) and is arranged around the driver's seat. The IG 51 is configured to output an ON / OFF signal to the ECU 60 when an ON / OFF operation is performed by the driver.

  The accelerator 52 is a pedal that the driver steps on to drive the fuel cell vehicle, and is arranged at the foot of the driver's seat. The accelerator 52 outputs the accelerator opening (depression amount) to the ECU 60.

<ECU>
The ECU 60 is a control device that electronically controls the fuel cell system 1 and includes a CPU, a ROM, a RAM, various interfaces, an electronic circuit, and the like, and exhibits various functions according to programs stored therein. In addition, various devices are controlled.

≪Operation of fuel cell system≫
Next, the operation of the fuel cell system 1 will be described with reference to FIGS.

<Basic operation>
First, the basic operation of the fuel cell system 1 will be described with reference to the basic control flow of FIG.
When the IG 51 is turned on, the ECU 60 that detects the ON signal starts the processing of FIG. The ECU 60 that has detected the ON signal opens the shut-off valve 22, supplies hydrogen to the anode channel 11, operates the compressor 31, supplies air (oxygen) to the cathode channel 12, and a refrigerant pump (not shown). Do not operate) to circulate the refrigerant.

  When the ECU 60 determines that the replacement of hydrogen and air has progressed, the OCV of the fuel cell stack 10 is equal to or higher than the predetermined OCV, and the fuel cell stack 10 is in a power generation enabled state, the ECU 60 controls the power controller 43 to extract current. The power generation of the fuel cell stack 10 is started. Next, the ECU 60 controls power generation of the fuel cell stack 10 and charge / discharge of the battery 41 based on the accelerator opening input from the accelerator 52.

  In step S200, the ECU 60 executes a warm-up priority determination process. Specific contents will be described later.

In step S101, the ECU 60 determines whether or not to perform normal control that does not promote warm-up of the battery 41 and / or the fuel cell stack 10. In addition, when going through step S205 (refer FIG. 3) mentioned later, it determines with normal control.
If it is determined that normal control is to be performed (Yes in S101), the process of the ECU 60 proceeds to step S106. On the other hand, when it is determined that normal control is not performed, that is, warming up of the battery 41 and / or the fuel cell stack 10 is promoted (S101, No), the process of the ECU 60 proceeds to step S102.

In step S102, the ECU 60 determines which of the battery 41 and the fuel cell stack 10 is preferentially warmed up.
Note that if the process goes through step S202 (see FIG. 3) described later, it is determined that the battery 41 is warmed up preferentially. If the process passes through step S204 (see FIG. 3) described later, the fuel cell stack 10 Is determined to warm up.

  When it is determined that the battery 41 is preferentially warmed up, the process of the ECU 60 proceeds to step S103. On the other hand, if it is determined that the fuel cell stack 10 is preferentially warmed up, the processing of the ECU 60 proceeds to step S107.

<Battery priority warm-up process>
In step S <b> 103, the ECU 60 executes a battery priority warm-up process that warms up the battery 41 with priority over the fuel cell stack 10.
Specifically, for example, with respect to the power supplied to the PDU 45 (motor) corresponding to the accelerator opening, the discharge power of the battery 41 is increased and the generated power of the fuel cell stack 10 is decreased with respect to the normal control. As described above, when the discharge power of the battery 41 is increased, the value of the current flowing through the battery 41 is increased. As a result, the amount of heat generated by the internal resistance of the battery 41 is increased. It will be.

  When the fuel cell vehicle is decelerating, the regenerative power from the motor 44 is preferentially charged to the battery 41, or the fuel cell stack 10 is excessively generated and the excess power is charged to the battery 41. As a result, warm-up of the battery 41 is promoted.

In addition, when charging / discharging the battery 41 in this way, control is performed so as not to overdischarge or overcharge.
Even when the battery 41 is preferentially warmed up as described above, the fuel cell stack 10 is generating electric power. Therefore, although not prioritized, the fuel cell stack 10 is also warmed up.

In step S104, the ECU 60 determines whether or not the warming up of the battery 41 has been completed.
For example, when the temperature of the battery 41 is equal to or higher than the battery warm-up completion temperature (for example, 20 to 30 ° C.) at which it is determined that the warm-up has been completed, it is determined that the warm-up of the battery 41 has been completed. In addition, when the warm-up completion time (for example, 5 minutes) determined to have been completed after the start of the battery-prioritized warm-up process in which the battery 41 is preferentially warmed up, the warm-up of the battery 41 is completed. It is determined.

  If it is determined that the warm-up of the battery 41 has been completed (S104 / Yes), the processing of the ECU 60 proceeds to step S105. On the other hand, when it is determined that the warm-up of the battery 41 has not been completed (No in S104), the process of the ECU 60 proceeds to Step S103.

In step S105, the ECU 60 determines whether or not the fuel cell stack 10 has been warmed up.
For example, when the temperature of the fuel cell stack 10 detected via the temperature sensor 14 is equal to or higher than the fuel cell stack warm-up completion temperature (for example, 30 to 40 ° C.) that is determined to be complete. It is determined that the warm-up of the stack 10 has been completed.

  If it is determined that the warm-up of the fuel cell stack 10 is complete (S105, Yes), the control of the ECU 60 proceeds to step 106. On the other hand, when it is determined that the warm-up of the fuel cell stack 10 has not been completed (No in S105), the process of the ECU 60 proceeds to step S107.

  In step S106, the ECU 60 normally controls power generation of the fuel cell stack 10 and charge / discharge of the battery 41 based on the accelerator opening.

<Fuel cell stack priority warm-up process>
In step S107, the ECU 60 executes a fuel cell stack priority warm-up process that warms up the fuel cell stack 10 with priority over the battery 41.
Specifically, for example, with respect to the power supplied to the PDU 45 (motor) corresponding to the accelerator opening, the generated power of the fuel cell stack 10 is increased and the discharged power of the battery 41 is decreased with respect to the normal control. As described above, when the generated power of the fuel cell stack 10 is increased, the current value flowing through the fuel cell stack 10 increases, and as a result, the amount of heat generated by the internal resistance of the fuel cell stack 10 increases. Ten warm-ups will be promoted.

  Further, even if the fuel cell vehicle is decelerating, the fuel cell stack 10 is caused to generate electric power and promote warm-up. In this case, the surplus power of the fuel cell stack 10 is charged in, for example, the battery 41 or consumed by the auxiliary device 48.

When the fuel cell stack 10 is caused to generate excessive power and charge the battery 41 in this way, control is performed so as not to overcharge.
Further, when the fuel cell stack 10 is warmed up preferentially, the flow rate of hydrogen and / or air is reduced to bring the fuel cell stack 10 closer to a state of hydrogen shortage and / or air shortage, and the internal resistance of the fuel cell stack 10 is reduced. You may make it raise.
Further, even when the fuel cell stack 10 is warmed up in priority as described above, the battery 41 is charged / discharged. Therefore, although not prioritized, the warming up of the battery 41 also proceeds.

In step S108, the ECU 60 determines whether or not the warm-up of the fuel cell stack 10 has been completed, as in step S105.
When it is determined that the warm-up of the fuel cell stack 10 has been completed (Yes in S108), the process of the ECU 60 proceeds to step S109. On the other hand, when it is determined that the warm-up of the fuel cell stack 10 has not been completed (No at S108), the process of the ECU 60 proceeds to step S107.

In step S109, the ECU 60 determines whether or not the warm-up of the battery 41 has been completed, as in step S104.
When it is determined that the warm-up of the battery 41 is complete (S109 / Yes), the process of the ECU 60 proceeds to step S106. On the other hand, when it is determined that the warm-up of the battery 41 has not been completed (No at S109), the process of the ECU 60 proceeds to step S103.

<Warm-up priority determination process S200>
Next, the contents of the warm-up priority determination process S200 for determining which of the battery 41 and the fuel cell stack 10 should be preferentially warmed up will be described with reference to FIG.

In step S201, the ECU 60 determines whether or not the temperature of the battery 41 (when the IG 51 is ON) is equal to or lower than a predetermined battery temperature (predetermined power storage device temperature).
The predetermined battery temperature is obtained by a preliminary test or the like, and is set to a temperature (for example, 0 ° C.) at which the battery 41 is determined to be warmed up when the temperature of the battery 41 is equal to or lower than the predetermined battery temperature.

Strictly speaking, after the IG 51 is turned on, hydrogen and air are supplied until the fuel cell stack 10 can generate power, that is, a certain short time has passed until the OCV becomes equal to or higher than the predetermined OCV. However, here, the temperature of the battery 41 when the process of the ECU 60 proceeds to step S201 is the temperature when the IG 51 is ON.
The same applies to the temperature of the fuel cell stack 10 in step S203 (when the IG 51 is ON) and the embodiments described later.

  When it is determined that the temperature of the battery 41 (when ON) is equal to or lower than the predetermined battery temperature (S201 / Yes), the process of the ECU 60 proceeds to step S202. On the other hand, when it is determined that the temperature of the battery 41 (when ON) is not lower than the predetermined battery temperature (No in S201), the process of the ECU 60 proceeds to step S203.

  As described above, the determination process (S201) regarding whether or not the battery 41 needs to be warmed up is executed prior to the determination process (S203) regarding whether or not the fuel cell stack 10 needs to be warmed up. The warming up of the battery 41, which is harder to warm than 10 and hard to warm up, is given priority.

In step S202, the ECU 60 temporarily stores, for example, a corresponding flag or the like that the battery 41 is warmed up preferentially.
Thereafter, the process of the ECU 60 proceeds to step S101 in FIG. 2 through the end.

In step S203, the ECU 60 determines whether or not the temperature of the fuel cell stack 10 (when the IG 51 is ON) is equal to or lower than a predetermined fuel cell stack temperature (predetermined power generator temperature).
The predetermined fuel cell stack temperature is obtained by a preliminary test or the like. When the temperature of the fuel cell stack 10 is equal to or lower than the predetermined fuel cell stack temperature, the temperature at which the fuel cell stack 10 is determined to be warmed up (for example, −10 ° C. ).

  If it is determined that the temperature of the fuel cell stack 10 (ON) is equal to or lower than the predetermined fuel cell stack temperature (Yes at S203), the process of the ECU 60 proceeds to step S204. On the other hand, when it is determined that the temperature of the fuel cell stack 10 (ON) is not lower than the predetermined fuel cell stack temperature (No at S203), the process of the ECU 60 proceeds to step S205.

In step S204, the ECU 60 temporarily stores that the fuel cell stack 10 is preferentially warmed up by using, for example, a corresponding flag.
Thereafter, the process of the ECU 60 proceeds to step S101 in FIG. 2 through the end.

In step S205, the ECU 60 temporarily stores the fact that the battery 41 or the fuel cell stack 10 is not warmed up preferentially and starts normally, for example, with a corresponding flag.
Thereafter, the process of the ECU 60 proceeds to step S101 in FIG. 2 through the end.

≪Effect of fuel cell system≫
According to such a fuel cell system 1, the following effects are obtained.

At the time of system startup, either one of the battery 41 and the fuel cell stack 10 is determined with priority over the other (S200), and determination is made (S102). Therefore, one of the batteries to be preferentially warmed up can be warmed up early (S103, S107).
In addition, since a special warming-up device such as an electric heater is not provided, the system configuration is simple and can be configured at low cost, and can be easily mounted on a fuel cell vehicle or the like.

  After the warm-up of one (battery 41 or fuel cell stack 10) to be preferentially warmed up, when the other warm-up is not complete (S105 No, S109 No), the other (fuel cell stack 10 or Since the battery 41) is warmed up (S107, S103), both the battery 41 and the fuel cell stack 10 can be reliably warmed up.

  If the temperature of the battery 41 when the IG 51 is ON is equal to or lower than a predetermined battery temperature (Yes in S201), it is determined that the battery 41 is preferentially warmed up (S202), that is, the fuel cell stack 10 needs to be warmed up. Since determination regarding whether or not the battery 41 needs to be warmed up is performed prior to determination regarding whether or not (S203), warming up of the battery 41 that is difficult to be warmed up can be prioritized.

≪Operation example of fuel cell system≫
Next, an operation example of the fuel cell system 1 (fuel cell vehicle) will be described with reference to FIGS.

<At acceleration>
First, with reference to FIG. 4, the acceleration time of the fuel cell vehicle (see FIG. 4A) will be described.
As shown in FIG. 4B, when the battery priority warm-up process for warming up the battery 41 is executed (S103), the fuel cell is compared with the normal control time (S106) in FIG. The generated power (power amount) of the stack 10 is reduced, and the discharged power (power amount) of the battery 41 is increased. Thereby, warming up of the battery 41 is promoted.

  On the other hand, as shown in FIG. 4C, when the fuel cell stack priority warm-up process for warming up the fuel cell stack 10 is executed (S107), during the normal control in FIG. 4D (S106). On the other hand, the discharge power (power amount) of the battery 41 is reduced and the generated power (power amount) of the fuel cell stack 10 is increased. Thereby, warm-up of the fuel cell stack 10 is promoted.

<Deceleration>
Next, referring to FIG. 5, the fuel cell vehicle will be decelerated (see FIG. 5A).
As shown in FIG. 5 (b), when the battery priority warm-up process for preferentially warming up the battery 41 is executed (S103), the fuel cell is compared with the normal control time (S106) of FIG. 5 (d). The stack 10 is excessively generated, and the generated power (electric power) is increased. Then, the excessively generated power of the fuel cell stack 10 and the regenerative power from the motor 44 are charged in the battery 41, and the charging power (power amount) of the battery 41 is increased. Thereby, warming up of the battery 41 is promoted.

On the other hand, as shown in FIG. 5 (c), when the fuel cell stack priority warm-up process for warming up the fuel cell stack 10 is executed (S107), during the normal control of FIG. 5 (d) (S106). On the other hand, the fuel cell stack 10 is excessively generated to increase the generated power (the amount of power). Thereby, warm-up of the fuel cell stack 10 is promoted.
Note that the battery 41 is charged with excess generated power of the fuel cell stack 10 and regenerative power from the motor 44.

≪Modification≫
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to this, For example, it can change as follows in the range which does not deviate from the meaning of this invention.

  In the above-described embodiment, the configuration in which the power storage device is the battery 41 is illustrated, but the type of the power storage device is not limited to this, and may be a capacitor, for example.

In the above-described embodiment, the case where the fuel cell system 1 is mounted on a fuel cell vehicle has been illustrated, but a configuration in which the fuel cell system 1 is mounted on another mobile body such as a motorcycle, a train, or a ship may be used.
Further, the present invention may be applied to a stationary fuel cell system for home use or a fuel cell system incorporated in a hot water supply system.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described with reference to FIGS.
In the second embodiment, the program set in the ECU 60 is partially different from the first embodiment, and the operation is partially different. Only the different parts will be described below.

<Warm-up priority determination process S300>
In the second embodiment, a warm-up priority determination process S300 in FIG. 6 is executed instead of the warm-up priority determination process S200 in FIG.

In step S301, the ECU 60 calculates the output recovery speed (kW / min) of the battery 41 when the IG 51 is ON based on the temperature of the battery 41 when the IG 51 is ON and the map of FIG.
Note that the map of FIG. 7 is obtained by a preliminary test or the like and stored in the ECU 60 in advance.

  The output recovery speed of the battery 41 is the recovery speed of the output of the battery 41 when the output of the battery 41 tries to recover to the output of the normal battery 41 that has been warmed up as the warm-up proceeds thereafter. That is, it means the increasing speed of the output of the battery 41.

As shown in FIG. 7, the output recovery speed of the battery 41 increases as the temperature of the battery 41 decreases when the IG 51 is ON.
On the other hand, as the temperature of the battery 41 when the IG 51 is ON is high and the battery 41 approaches a warm state, that is, a state where warm-up is not required, normal output is possible when the IG 51 is ON. The recovery speed approaches 0 (kW / min).

Here, with reference to FIG. 7, the output recovery speed (kW / min) of the fuel cell stack 10 will also be described.
The output recovery speed of the fuel cell stack 10 is the fuel cell when the output of the fuel cell stack 10 is about to recover to the output of the normal fuel cell stack 10 that has been warmed up as the warm-up proceeds thereafter. This means the recovery speed of the output of the stack 10, that is, the increase speed of the output of the fuel cell stack 10.

As shown in FIG. 7, as with the battery 41, the output recovery speed of the fuel cell stack 10 increases as the temperature of the fuel cell stack 10 when the IG 51 is ON decreases.
On the other hand, as the temperature of the fuel cell stack 10 when the IG 51 is ON is high and the fuel cell stack 10 approaches a warm state, that is, a state where the warm-up is not required, normal output can be performed from the time when the IG 51 is ON. The output recovery speed of the fuel cell stack 10 approaches 0 (kW / min).

  Further, as described above, since the battery 41 is less likely to be heated than the fuel cell stack 10 and is not easily warmed up, as shown in FIG. 7, in the low temperature region of 0 ° C. or lower, the output recovery speed of the battery 41 is It tends to be smaller than the output recovery speed of the fuel cell stack 10.

  In step S302, the ECU 60 calculates the output recovery speed (kW / min) of the fuel cell stack 10 when the IG 51 is ON based on the temperature of the fuel cell stack 10 when the IG 51 is ON and the map of FIG. .

  In step S303, the ECU 60 determines whether or not the output recovery speed of the battery 41 calculated in step S301 (when ON) is greater than the output recovery speed of the fuel cell stack 10 calculated in step S302 (when ON).

If it is determined that the output recovery speed of the battery 41 (when ON) is greater than the output recovery speed of the fuel cell stack 10 (when ON) (S303, Yes), the processing of the ECU 60 proceeds to step S304.
On the other hand, when it is determined that the output recovery speed of the battery 41 (when ON) is not greater than the output recovery speed of the fuel cell stack 10 (when ON) (No in S303), the process of the ECU 60 proceeds to step S305.

In step S304, the ECU 60 temporarily stores that the battery 41 is preferentially warmed up, for example, by a corresponding flag.
Thereafter, the processing of the ECU 60 returns to the basic control flow of FIG. 2 through the end. Note that the determination process in step S101 is omitted, and the process proceeds to step S102.

In step S305, the ECU 60 temporarily stores that the fuel cell stack 10 is preferentially warmed up by using, for example, a corresponding flag.
Thereafter, the processing of the ECU 60 returns to the basic control flow of FIG. 2 through the end. Note that the determination process in step S101 is omitted, and the process proceeds to step S102.

<< Effects of Second Embodiment >>
According to such 2nd Embodiment, the following effects are acquired.
The output recovery speed of the battery 41 when the IG 51 is ON is compared with the output recovery speed of the fuel cell stack 10 (S303), and it is determined that the one with the higher output recovery speed is preferentially warmed up. The battery 41 or the fuel cell stack 10 having a high output recovery speed can be preferentially warmed up preferentially.

«Third embodiment»
Next, a third embodiment of the present invention will be described with reference to FIGS.
In the third embodiment, the programs set in the ECU 60 are partially different from those in the first embodiment, and the operations are partially different. Only the different parts will be described below.

<Warm-up priority determination process S400>
In the third embodiment, a warm-up priority determination process S400 in FIG. 8 is executed instead of the warm-up priority determination process S200 in FIG.

In step S401, the ECU 60 calculates the maximum output (kW) of the battery 41 at the temperature when the IG 51 is ON based on the temperature of the battery 41 when the IG 51 is ON and the map of FIG.
Note that the map of FIG. 9 is obtained by a preliminary test or the like and stored in the ECU 60 in advance.

As shown in FIG. 9, the maximum output of the battery 41 at the temperature when the IG 51 is ON decreases as the temperature of the battery 41 when the IG 51 is ON decreases.
On the other hand, as the temperature of the battery 41 is high when the IG 51 is ON and the battery 41 approaches a warm state, that is, a state where warm-up is not required, the maximum output at the normal time is approached.

Here, with reference to FIG. 9, the maximum output (kW) of the fuel cell stack 10 will also be described.
Similar to the battery 41, the maximum output of the fuel cell stack 10 decreases as the temperature of the fuel cell stack 10 when the IG 51 is ON decreases.
On the other hand, as the temperature of the fuel cell stack 10 is high when the IG 51 is ON and the fuel cell stack 10 approaches a warm state, i.e., a state where no warm-up is required, the maximum output during normal operation is approached.

  In step S402, the ECU 60 calculates the maximum output (kW) of the fuel cell stack 10 at the temperature when the IG 51 is ON based on the temperature of the fuel cell stack 10 when the IG 51 is ON and the map of FIG.

  In step S403, the ECU 60 calculates the first difference by subtracting the maximum output of the battery 41 when the IG 51 is ON calculated in step S401 from the normal maximum output of the battery 41 (see FIG. 9).

  In step S404, the ECU 60 calculates the second difference by subtracting the maximum output of the fuel cell stack 10 when the IG 51 is ON calculated in step S402 from the normal maximum output of the fuel cell stack 10 (see FIG. 9). ).

  In step S405, the ECU 60 compares the first difference for the battery 41 with the second difference for the fuel cell stack 10, and specifically determines whether or not the first difference is greater than the second difference.

  When it is determined that the first difference is greater than the second difference (S405 / Yes), the process of the ECU 60 proceeds to step S406. On the other hand, when it determines with a 1st difference not being larger than a 2nd difference (S405 * No), the process of ECU60 progresses to step S407.

In step S406, the ECU 60 temporarily stores, for example, a corresponding flag or the like that the battery 41 is preferentially warmed up.
Thereafter, the processing of the ECU 60 returns to the basic control flow of FIG. 2 through the end. Note that the determination process in step S101 is omitted, and the process proceeds to step S102.

In step S407, the ECU 60 temporarily stores that the fuel cell stack 10 is preferentially warmed up, for example, by a corresponding flag.
Thereafter, the processing of the ECU 60 returns to the basic control flow of FIG. 2 through the end. Note that the determination process in step S101 is omitted, and the process proceeds to step S102.

<< Effects of Third Embodiment >>
According to such 3rd Embodiment, the following effect is acquired.
Comparing the first difference between the maximum output of the battery 41 when the IG 51 is ON and the maximum output at the normal time, and the second difference between the maximum output of the fuel cell stack 10 at the ON time and the maximum output at the normal time; Since it is determined to warm up with priority on the larger difference, it is possible to actively warm up the larger difference, that is, the greater recovery margin.

<< Fourth Embodiment >>
Next, a fourth embodiment of the present invention will be described with reference to FIGS.
A hybrid system 2 (power supply system) according to the fourth embodiment shown in FIG. 10 is mounted on a hybrid vehicle. The hybrid system 2 includes an engine 71 and a generator 72 as a power generation device, and a temperature sensor 73 (second temperature sensor) instead of the fuel cell stack 10 (see FIG. 1).
In addition, the apparatus (hydrogen tank 21 etc.) regarding hydrogen supply / discharge and the apparatus (compressor 31 etc.) regarding air supply / discharge are not provided.

  The engine 71 is a four-stroke engine that repeats four cycles (intake, compression, combustion / expansion, and exhaust). The output (rotation speed, torque, etc.) of the engine 71 is controlled by the ECU 60 that controls the intake amount of fuel / air and the ignition timing.

  The generator 72 is a device that operates by the power of the engine 71 to generate electric power. Specifically, the generator 72 is mechanically connected to the crankshaft of the engine 71 via an acceleration or deceleration mechanism and a clutch (not shown). The electric power generated by the generator 72 is supplied to the electric power controller 43.

  The temperature sensor 73 is a sensor that detects the temperature of the engine 71, and is attached to an appropriate position of the engine 71. The temperature sensor 73 is configured to output the temperature of the engine 71 to the ECU 60.

  In such a hybrid system 2, the ECU 60 preferentially warms up either the battery 41 or the engine 71 based on the temperature of the battery 41 and the temperature of the engine 71 (generator 72) when the IG 51 is ON. It is set to judge.

  In addition, as in the second embodiment, the output recovery speed (kW / min) of the generator 72 (engine 71) is calculated based on the temperature of the engine 71 when the IG 51 is ON and the map of FIG. Then, this may be compared with the output recovery speed of the battery 41, and the warming-up may be performed with priority given to the one with the higher output recovery speed.

  Similarly to the third embodiment, the second difference between the maximum output of the generator 72 (engine 71) at the temperature of the engine 71 when the IG 51 is ON and the maximum output of the generator 72 at the normal time (see FIG. 12). ), The first difference with respect to the battery 41 may be compared, and the one with the larger difference may be preferentially warmed up.

1 Fuel cell system (power supply system)
2 Hybrid system (power supply system)
10 Fuel cell stack (power generation device)
14 Temperature sensor (second temperature sensor)
41 battery (power storage device)
42 Temperature sensor (first temperature sensor)
43 Power controller (power generation control means, charge / discharge control means)
51 IG (Start-up switch)
60 ECU (control means)
71 Engine (power generator)
72 Generator (Generator)
73 Temperature sensor (second temperature sensor)

Claims (7)

A power storage device capable of charging and discharging electric power;
A power generation device capable of charging power to the power storage device;
A first temperature sensor for detecting a temperature of the power storage device;
A second temperature sensor for detecting the temperature of the power generation device;
Control means for controlling charge / discharge of the power storage device and power generation of the power generation device;
A startup switch that is turned on when starting the system;
With
When the control means detects the ON signal of the start switch and starts the system,
Based on the temperature of the power storage device and the temperature of the power generation device when the start switch is ON, it is determined whether to warm up the power storage device or the power generation device with priority over the other,
A power supply system characterized in that the one warm-up to be preferentially warmed up is promoted more than the other warm-up . 2. The control unit according to claim 1, wherein after the warm-up of the one that should be preferentially warmed up, when the warm-up of the other is not completed, the control unit promotes the warm-up of the other. Power supply system. 3. The control unit according to claim 1, wherein when the temperature of the power storage device at the time of ON is equal to or lower than a predetermined power storage device temperature, the control unit determines that the power storage device is preferentially warmed up. Power supply system. The control means includes
Compare the output recovery speed of the power storage device at the temperature at the ON time with the output recovery speed of the power generation device at the temperature at the ON time,
3. The power supply system according to claim 1, wherein the power supply system is determined to preferentially warm up one of the power storage device and the power generation device that has a higher output recovery speed. 4. The control means includes
A first difference between the maximum output of the power storage device at a temperature at the time of ON and the maximum output of the power storage device at a normal time;
A second difference between the maximum output of the power storage device at a temperature at the time of ON and the maximum output of the power storage device at a normal time;
Compare
3. The power supply system according to claim 1, wherein warming-up is determined by giving priority to a larger one of the first difference and the second difference. 6. The electric power according to claim 1, wherein the control unit increases charging power or discharging electric power with respect to a normal time when promoting warm-up of the power storage device. Supply system. The power supply system according to any one of claims 1 to 6, wherein the control unit increases the output with respect to a normal time when promoting warm-up of the power generation device.

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