JP5804751B2 - High pressure gas supply system - Google Patents

Description

  The present invention relates to a high-pressure gas supply system corresponding to a low temperature environment.

  Various high-pressure gas supply systems including a high-pressure fuel tank have been proposed that include a fuel supply device that supplies fuel decompressed by a pressure reducing valve from a fuel tank to a fuel consuming device (engine, fuel cell, etc.). In such a system, for example, when a malfunction occurs in the fuel pressure adjustment function in the fuel supply device, a technique for driving the fuel cutoff valve to shut off the high-pressure gas flow path has been proposed (see Patent Document 1). . Also, if the gas temperature in the fuel tank falls below the system guarantee temperature in a low temperature environment, the function of the valve seal may be impaired, so the fuel consumption is based on the temperature of the fuel released from the fuel tank. A technique for limiting the output taken out from the device has been proposed (see Patent Document 2).

JP 63-41651 A JP 2006-344492 A

  However, in the conventional high-pressure gas supply system, when the fuel consuming equipment is continuously operated at a high load in a pressure region where the tank pressure is lower than the filling pressure, the output limit start temperature is higher than the valve performance guarantee temperature. Therefore, even if the gas temperature (fuel temperature) does not reach (decrease) the performance guarantee temperature of the valve, the control to limit the output works and the output is limited more than necessary. It was.

  This invention solves the said conventional problem, and makes it a subject to provide the high pressure gas supply system which can prevent restrict | limiting an output more than necessary.

The present invention controls a fuel tank that supplies fuel accumulated therein to a fuel cell, a supply device that supplies fuel in the fuel tank to the fuel cell, and a fuel consumption amount of fuel consumed in the fuel cell. Fuel consumption control means, fuel temperature detection means for detecting the fuel temperature of the fuel discharged from the fuel tank, environmental temperature detection means for detecting the environmental temperature in which the fuel tank is placed, and the fuel tank comprising a tank pressure detecting means for detecting a tank pressure of the inner, and defines the relationship between the maximum fuel temperature decrease value when the fuel cell with the previous SL tank pressure is continuously operated at full load for each of the environmental temperature, the fuel consumption control means, when limiting the fuel consumption on the basis of the detected said fuel temperature, before Symbol ambient temperature and the said maximum fuel temperature decrease value determined from the tank pressure fuel Wherein the sum of the temperature relaxes the restriction is higher than the performance guarantee temperature of the supply device.

According to this, when the tank pressure is low (remaining fuel is low), the fuel consumption (output of the fuel cell, etc.) is required by using the fact that the temperature drop is considered to be small and relaxing the restriction. It can prevent restricting to the above. Note that “relaxing the restriction” includes “removing the restriction (no restriction)”.
In addition, if the sum of the current fuel cell temperature and the fuel temperature drop value is higher than the guaranteed performance temperature of the supply device, it can be determined that the sum will not reach the guaranteed performance temperature, so the restriction is relaxed. can do. On the contrary, when the sum is equal to or lower than the performance guarantee temperature, it can be determined that the sum reaches the performance guarantee temperature. Therefore, control for limiting the fuel consumption is performed without relaxing the restriction. Therefore, it can be accurately determined whether or not the restriction on the fuel consumption needs to be relaxed.
Also, since the relationship between the tank pressure and the fuel temperature drop value changes depending on whether the environment temperature is high or low, the relationship between the tank pressure and the fuel temperature drop value is determined for each environmental temperature, and the fuel consumption The control means can determine more accurately whether or not the restriction on the fuel consumption needs to be relaxed based on the relationship between the tank pressure determined for each environmental temperature and the fuel temperature drop value.

  The fuel consumption control means limits the output of the fuel cell.

  According to this, the fuel consumption control means can limit the output of the fuel cell, so that the amount of fuel released from the fuel tank can be suppressed. Problems in the supply device (for example, a decrease in the sealing function of the valve) can be prevented.

  The fuel consumption control means limits the amount of fuel supplied to the fuel cell.

  According to this, the fuel consumption control means can suppress the amount of fuel released from the fuel tank by limiting the amount of fuel supplied to the fuel cell, so that the fuel temperature can be reduced rapidly. It is possible to prevent problems in the supply device (for example, a decrease in the sealing function of the valve).

  ADVANTAGE OF THE INVENTION According to this invention, the high pressure gas supply system which can prevent restrict | limiting an output more than necessary can be provided.

It is a whole lineblock diagram showing the high-pressure gas supply system concerning this embodiment. It is a flowchart which shows operation | movement of the high pressure gas supply system which concerns on 1st Embodiment. It is a map which shows the relationship between a tank pressure and a temperature fall amount. It is a map which shows the relationship between gas temperature and the output of a fuel cell. (A) is a time chart which concerns on this embodiment, (b) is a time chart which concerns on a comparative example. It is a flowchart which shows the modification of operation | movement of a high pressure gas supply system. It is a map which shows the relationship between gas temperature and gas supply amount.

  Hereinafter, the high-pressure gas supply system 1 according to the present embodiment will be described with reference to FIGS. 1 to 7. In the following description, the high-pressure gas supply system 1 for a vehicle in which the high-pressure gas supply system 1 is applied to a fuel cell vehicle will be described as an example. However, the present invention is not limited to this, and is not limited to this. It may be a gas supply system or a stationary high-pressure gas supply system for home use or business use.

  As shown in FIG. 1, the high-pressure gas supply system 1 is applied to a fuel cell system F1. A hydrogen tank 10 (fuel tank) and hydrogen gas (fuel) in the hydrogen tank 10 are supplied to a fuel cell 11. Supply device 20 and ECU (Electronic Control Unit) 50 are provided.

  The hydrogen tank 10 is a container filled with high-purity hydrogen as a fuel at a high pressure (for example, 35 MPa). Further, the hydrogen tank 10 includes a gas temperature sensor 41 (fuel temperature detecting means) configured by a thermistor for detecting the temperature of hydrogen in the tank, and a pressure sensor 42 (tank pressure) for detecting the pressure of hydrogen in the tank. Detection means) are provided.

  For example, the hydrogen tank 10 is formed of an aluminum alloy and has a liner (not shown) for storing hydrogen gas at a high pressure therein, and the periphery of the liner is CFRP (Carbon Fiber Reinforced Plastic). Or a reinforced layer (not shown) formed of GFRP (Glass Fiber Reinforced Plastic) or the like.

  The fuel cell 11 is a fuel cell stack configured by stacking a plurality of solid polymer type single cells (not shown), and the plurality of single cells are electrically connected in series. The single cell includes an MEA (Membrane Electrode Assembly), and a conductive anode separator (not shown) and a cathode separator (not shown) sandwiching the MEA.

  The MEA includes an electrolyte membrane (solid polymer membrane) made of a monovalent cation exchange membrane (for example, perfluorosulfonic acid type), and an anode and a cathode sandwiching the electrolyte membrane. The anode and cathode are mainly composed of a conductive porous material such as carbon paper, and contain a catalyst (Pt, Ru, etc.) for causing an electrode reaction in the anode and cathode.

  The anode separator 12 is formed with an anode flow path 12 formed of a groove for supplying and discharging hydrogen to and from the anode of each MEA. The cathode separator is formed with a cathode channel 13 formed by a groove for supplying and discharging air to and from the cathode of each MEA.

  When hydrogen is supplied to each anode through the anode flow channel 12 and air (oxygen) is supplied to each cathode through the cathode flow channel 13, a potential difference (OCV (Open Circuit Voltage) is generated in each single cell. ), Open circuit voltage). Next, when the fuel cell 11 and an external load such as a travel motor (power source of a fuel cell vehicle) 62 are electrically connected and a current is taken out, the fuel cell 11 generates power.

  The supply device 20 is provided in the anode hydrogen supply line of the fuel cell system F1, and in order from the upstream side, the normally closed first shut-off valve 21, the pipe a1, the first pressure reducing valve 22, the pipe a2, A relief valve 23, a pipe a3, a normally closed second shutoff valve 24, a pipe a4, a second pressure reducing valve 25, a pipe a5, an ejector 26, and a pipe a6 are provided.

  The first shut-off valve 21 is, for example, an in-tank electromagnetic valve provided integrally with the hydrogen tank 10 and is opened and closed under the control of the ECU 50.

  The first pressure reducing valve 22 is for reducing the high-pressure hydrogen supplied from the hydrogen tank 10 to a predetermined pressure value (intermediate pressure).

  The relief valve 23 is used when the pressure of the pipes a2, a3, a4 between the first pressure reducing valve 22 and the second pressure reducing valve 25 exceeds a predetermined pressure with respect to the pressure reduced by the first pressure reducing valve 22. It is supposed to open. The relief valve 23 may be mechanically opened or may be opened by an electrical signal.

  The second shutoff valve 24 is opened under the control of the ECU 50, thereby supplying hydrogen decompressed by the first pressure reducing valve 22 to the second pressure reducing valve 25.

  The second pressure reducing valve 25 reduces the pressure of the hydrogen reduced by the first pressure reducing valve 22 so that the pressure of the hydrogen supplied to the fuel cell 11 via the ejector 26 becomes an appropriate pressure (low pressure). In the second pressure reducing valve 25, for example, the pressure of air from the compressor 30 described later to the cathode flow path 13 is input as a signal pressure (pilot pressure), and the pressure of hydrogen is set based on the input air pressure. It comes to control. Further, the second pressure reducing valve 25 may be a pressure reducing device by an electrical signal.

  The ejector 26 is a type of vacuum pump that returns unreacted hydrogen discharged from the anode flow path 12 of the fuel cell 11 to the anode flow path 12 of the fuel cell 11 via the pipe a7. Although not shown, the ejector 26 has a metal housing, a nozzle that injects hydrogen into the housing, a needle that is inserted through the nozzle and changes the opening diameter of the nozzle, and drives the needle A drive unit having a solenoid to be operated is accommodated.

  A pipe 8 is branched and connected to the pipe a7 connected to the outlet of the anode flow path 12, and a purge valve 27 is provided in the pipe a8. The purge valve 27 is opened under the control of the ECU 50, for example, so that impurities (water vapor) accompanying hydrogen circulating in the hydrogen circulation passage (anode passage 12, pipes a6, a7) when the fuel cell 11 generates power. , Nitrogen, etc.). As the timing for opening the purge valve 27 and discharging impurities, for example, the minimum cell voltage input from a cell voltage monitor (not shown) for detecting the voltage of a single cell of the fuel cell 11 is equal to or lower than a predetermined cell voltage. It is time to become. The purge valve 27 may be opened regularly (every predetermined time) by the ECU 50.

  The cathode system of the fuel cell system F1 includes a compressor 30, a humidifier (not shown), a back pressure valve, a diluter, and the like.

  The compressor 30 is composed of a supercharger or the like driven by a motor, and is connected to the inlet of the cathode channel 13 via a pipe b1. When the compressor 30 is driven by the control of the ECU 50, the air taken from the outside of the vehicle is supplied to the cathode flow path 13. The rotation speed of the motor of the compressor 30 is set to be increased so that air is supplied at a large flow rate and a high pressure when the amount of depression (accelerator opening) of an accelerator pedal (not shown) increases. Thus, when the rotation speed of the compressor 30 increases, the amount of hydrogen consumed in the fuel cell 11 increases.

  The humidifier includes a plurality of hollow fiber membranes capable of exchanging moisture. Between the air supplied to the fuel cell 11 via the hollow fiber membranes and the humid cathode off-gas discharged from the cathode channel 13. Thus, the air is exchanged and the air supplied to the fuel cell 11 is humidified.

  The back pressure valve is constituted by a normally open type valve that can be adjusted in opening degree, such as a butterfly valve, and is provided in the pipe b2. For example, the opening degree of the back pressure valve is controlled to be reduced (squeezed) by the ECU 50 to supply air at a high pressure when the accelerator pedal is depressed.

  The diluter is provided in the pipe b2 downstream of the back pressure valve. The anode offgas discharged from the purge valve 27 through the pipe a8 is introduced, and after hydrogen in the anode offgas is diluted with the cathode offgas, It is configured to discharge.

  The fuel cell system F1 includes a VCU (Voltage Control Unit) 61, a travel motor 62, a high voltage battery 63, and the like as a power consumption system.

  The VCU 61 has a function of controlling (limiting) the generated power (generated current) of the fuel cell 11 based on the power generation command output from the ECU 50. That is, when a command for increasing the generated power to the VCU 61 is input from the ECU 50, the amount of hydrogen released from the hydrogen tank 10 increases, and conversely, a command for decreasing the generated power to the VCU 61 is issued from the ECU 50. When input, the amount of hydrogen released from the hydrogen tank 10 decreases. In the present embodiment, the ECU 50 and the VCU 61 constitute fuel consumption control means.

  The travel motor 62 is constituted by a permanent magnet type three-phase AC synchronous motor or the like and serves as a power source for the fuel cell vehicle, and is connected to the VCU 61 via a PDU (Power Drive Unit) (not shown).

  The high voltage battery 63 is composed of a chargeable / dischargeable battery such as a lithium ion battery, and charging / discharging is controlled by the VCU 61. The high voltage battery 63 assists the electric power from the fuel cell 11 when the vehicle suddenly accelerates and supplies it to the traveling motor 62, and is used for the electric power (such as the compressor 30) when the fuel cell system F1 is started. .

  The ignition switch (IG) 64 is a start switch of the fuel cell system F1 (fuel cell vehicle). When it is turned on, power generation of the fuel cell 11 is started, and when it is turned off, power generation of the fuel cell 11 is performed. Stopped.

  The ECU 50 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), various interfaces, an electronic circuit, and the like. The ECU 50 also detects the temperature T1 (fuel temperature) in the hydrogen tank 10 detected by the temperature sensor 41, the pressure P (tank pressure) in the hydrogen tank 10 detected by the pressure sensor 42, and the outside air temperature sensor 43 (environment temperature). The outside air temperature T2 (environment temperature) detected by the detecting means) is acquired. The outside air temperature sensor 43 detects the temperature around the hydrogen tank 10 and is disposed, for example, in the vicinity of the hydrogen tank 10 (outside the vehicle).

  The ECU 50 has a function of limiting the amount of hydrogen consumed (fuel consumption) consumed by the fuel cell 11 based on the detected gas temperature (fuel temperature) T1 in the hydrogen tank 10. Here, when limiting the consumption of hydrogen, in addition to the above gas temperature, a temperature decrease amount (fuel temperature decrease value) determined by the detected tank pressure is used to determine whether or not to relax the limit. To do.

  The temperature decrease amount is, for example, a temperature decrease amount (maximum) when the vehicle (fuel cell vehicle) is continuously operated (continuous running) at a maximum load at an outside air temperature (vehicle guaranteed temperature, for example, minus 20 ° C.) guaranteed. Value). A map in which such a temperature decrease amount is determined for each tank pressure is shown in FIG.

  For example, the ECU 50 is configured to relax the above-described restriction when the sum of the gas temperature (fuel temperature) and the temperature decrease amount (fuel temperature decrease value) is higher than the performance guarantee temperature of the supply device 20. . In this embodiment, the guaranteed performance temperature of the supply device 20 is, for example, the guaranteed performance temperature of the first shut-off valve 21, in other words, the guaranteed temperature (performance guaranteed temperature) of the seal portion of the first shut-off valve 21. As described above, when the sum of the current gas temperature and the temperature drop amount is higher than the performance guarantee temperature of the first shut-off valve 21, the gas temperature does not fall below the performance guarantee temperature. The amount limit can be relaxed.

  In addition, the relaxation of the restriction is intended to include no restriction (eliminating the restriction), that is, when driving at the maximum load, control is performed so as to continue the driving (running) at the maximum load. There is a case. Further, the relaxation of the restriction is not limited to not restricting, but also includes controlling to literally relax the restriction (so that the degree of restriction becomes small). Therefore, in the present embodiment, “relaxing the restriction” means not only the case where the restriction is relaxed but also the case where the restriction is removed (when the restriction is not restricted).

  Next, the operation of the fuel cell system F1 including the high-pressure gas supply system 1 according to the present embodiment will be described with reference to FIGS. 2 to 5 (refer to FIG. 1 as appropriate).

  When the ECU 50 detects an ON signal from the IG 64 of the fuel cell system F1, the ECU 50 opens the first cutoff valve 21 and the second cutoff valve 24, and drives the compressor 30. As a result, hydrogen is supplied from the hydrogen tank 10 to the anode of the fuel cell 11, and air (oxygen) is supplied to the cathode of the fuel cell 11, so that the fuel cell 11 starts power generation. Note that when the hydrogen is released from the hydrogen tank 10, the temperature in the hydrogen tank 10 decreases, and the temperature of the first cutoff valve 21 also decreases.

  In step S101, the ECU 50 acquires the gas temperature (fuel temperature) T1 in the hydrogen tank 10 detected by the gas temperature sensor 41.

  And it progresses to step S102 and ECU50 determines whether the gas temperature T1 acquired by step S101 is below a predetermined value. The predetermined value is a threshold value (output limit start temperature A) for determining whether or not it is necessary to start the output limit of the generated power of the fuel cell 11, and for example, the performance guarantee temperature B of the first shutoff valve 21 It is set to minus 35 ° C. higher than (eg minus 40 ° C.).

  In step S102, if the ECU 50 determines that the gas temperature T1 is equal to or lower than the predetermined value (Yes), it determines that it is necessary to start the output limitation of the fuel cell 11, and proceeds to step S103.

  In step S103, the ECU 50 acquires the outside air temperature (environment temperature) T2 detected by the outside air temperature sensor 43, and further acquires the tank pressure P detected by the pressure sensor 42.

  Proceeding to step S104, the ECU 50 determines a minimum temperature estimated based on the gas temperature T1 acquired in step S101, the tank pressure P acquired in step S103, and the outside air temperature T2, and the determined minimum temperature is the first temperature. It is determined whether or not the temperature is below the performance guarantee temperature B (seal guarantee minimum temperature) of the shut-off valve 21. That is, the temperature decrease amount ΔT is calculated based on the map of FIG. 3 showing the relationship between the tank pressure P and the temperature decrease amount ΔT obtained for each outside air temperature T2 (for each environmental temperature), and the calculated temperature decrease amount The sum of ΔT and the current gas temperature T1 is determined (estimated) as the minimum temperature.

  The map of FIG. 3 is related so that the temperature decrease amount ΔT decreases as the tank pressure P decreases, and the map related in this way is obtained for each outside air temperature T2 and stored in the ECU 50. Has been. That is, in the case of the hydrogen tank 10 when the tank pressure P is high (for example, 35 MPa) and the case of the hydrogen tank 10 when the tank pressure P is low (for example, 10 MPa), respectively, through the first shut-off valve 21 under the same conditions. Assuming that hydrogen is released, since the adiabatic expansion is proportional to the pressure, the pressure difference is smaller when the tank pressure P is lower than when the tank pressure P is high. By becoming less. Further, the map is set so that, at the same tank pressure P, the temperature decrease amount ΔT decreases as the outside air temperature T2 increases, and the temperature decrease amount ΔT increases as the outside air temperature T2 decreases.

  In step S104, when the ECU 50 determines that the minimum temperature is equal to or lower than the performance guarantee temperature B of the first cutoff valve 21 (Yes), the ECU 50 proceeds to step S105.

  In step S105, the ECU 50 controls to limit the output of the fuel cell 11 based on the output restriction map (solid line portion) shown in FIG. Note that the map shown in FIG. 4 shows the relationship between the gas temperature and the output (FC output, fuel consumption) of the fuel cell (FC) 11, for example, the output restriction start temperature (predetermined value). When A is set to minus 35 ° C. and the performance guarantee temperature (seal guarantee minimum temperature) B is set to minus 40 ° C., the output of the fuel cell 11 decreases as the gas temperature decreases, that is, the output of the fuel cell 11 The limit is set to be large. Further, the map shown in FIG. 4 is obtained in advance by experiments, simulations, and the like, and is stored in the ECU 50.

  That is, the ECU 50 gives a power generation command to the VCU 61 so that the output (FC output, generated power) of the fuel cell 11 becomes low. By limiting the output of the fuel cell 11 in this way, the amount of hydrogen released from the hydrogen tank 10 via the first shut-off valve 21 is reduced, and a decrease in the temperature of hydrogen in the hydrogen tank 10 is suppressed. By suppressing a decrease in the temperature of the first shut-off valve 21, it is possible to avoid the gas temperature from falling below the performance guarantee temperature B of the first shut-off valve 21.

  On the other hand, if the ECU 50 determines in step S104 that the minimum temperature is not lower than the performance guarantee temperature B of the first cutoff valve 21 (No), that is, the minimum temperature is the performance guarantee temperature B of the first cutoff valve 21. If it is determined that the value is not lower, the process proceeds to step S106.

In step S106, the ECU 50 relaxes the output restriction of the fuel cell 11. That is, as indicated by one broken line in FIG. 4, the ECU 50 controls the VCU 61 so that the output limit value becomes smaller (relaxes the output limit) than the FC output limit (solid line portion) set in step S105. To do. By reducing the output limit value, the amount of hydrogen released from the hydrogen tank 10 via the first cutoff valve 21 increases .

In step S106, the case where the output restriction of the fuel cell 11 is relaxed has been described as an example. However, the present invention is not limited to this, and as shown by the other broken line in FIG. Control may be performed so as not to limit (remove the limit, zero limit). This also increases the amount of hydrogen released from the hydrogen tank 10 through the first cutoff valve.

  In step S102, when the ECU 50 determines that the gas temperature T1 is not equal to or lower than the predetermined value (No), the ECU 50 returns.

  Further, when the output of the fuel cell 11 is restricted based on the output restriction map indicated by the solid line in FIG. 4 (S105), the ECU 50 determines that the minimum temperature is not lower than the performance guarantee temperature B. (S104, No), control is performed so that the output restriction is relaxed (or the output restriction becomes zero) with respect to the output restriction map indicated by the solid line in FIG.

  By the way, as shown in FIG. 5B as a comparative example, when the gas temperature is equal to or lower than the output restriction start temperature A (predetermined value), it is assumed that continuous operation is performed at the maximum load (load upper limit, for example, maximum vehicle speed). However, even in a situation where the performance guarantee temperature B of the first shutoff valve 21 is not reached, the output restriction works. Therefore, in the present embodiment, as shown in FIG. 5A, even when the gas temperature is equal to or lower than the output restriction start temperature A (predetermined value), the first shut-off valve 21 is used even when continuously operating at the maximum load. When the temperature does not fall below the guaranteed performance temperature B, the output is not limited.

  FIG. 5A shows a case in which continuous running is continued at the maximum load (load upper limit) without limiting the output when the minimum temperature does not fall below the guaranteed performance temperature B in a situation where the output is not being limited. . Note that the present embodiment is not limited to the case where the output is not limited in the situation where the output is not being restricted as described above, and the output restriction is more relaxed than the output restriction of the pattern shown in FIG. You may make it become. It also includes the case where the output restriction is relaxed in a situation where the output is being restricted.

  As described above, the high-pressure gas supply system 1 according to the present embodiment restricts the output (fuel consumption) of the fuel cell 11 based on the gas temperature T1 detected by the gas temperature sensor 41. In addition, the output limit of the fuel cell 11 is relaxed (or not limited) using the temperature decrease amount (fuel temperature decrease value) ΔT determined from the tank pressure P detected by the pressure sensor 42. It is a thing. According to this, when the tank pressure P is low (the remaining gas is small), even if the continuous operation is performed at the maximum load (even if the fuel is consumed continuously), the temperature decrease amount is small, and the tank pressure is When the temperature is high (the amount of residual gas is large), the amount of temperature decrease increases when the fuel cell is continuously operated at the maximum load (when the fuel is continuously consumed). Therefore, when the tank pressure P is low (the remaining gas is small), the amount of temperature decrease is small, so that the output restriction can be relaxed (or the output restriction can be avoided). Therefore, the output of the fuel cell 11 is not restricted more than necessary, and the merchantability of the high-pressure gas supply system 1 (fuel cell system F1, vehicle) can be prevented from being lowered.

  Further, according to the present embodiment, the ECU 50 (fuel consumption control means) determines that the fuel when the sum of the current gas temperature T1 and the temperature decrease amount ΔT is higher than the performance guarantee temperature B of the first shutoff valve 21. By relaxing the output limit of the battery 11, it is possible to accurately determine whether or not the output limit of the fuel cell 11 needs to be relaxed.

  In addition, according to the present embodiment, the map includes the outside temperature sensor 43 that detects the outside temperature T2 (environment temperature), and defines the relationship between the tank pressure P and the temperature decrease amount ΔT for each outside temperature T2 (FIG. 3). By relieving the output limit of the fuel cell 11 based on the reference), it can be determined with higher accuracy whether or not the output limit of the fuel cell 11 needs to be relaxed.

  Further, according to the present embodiment, the ECU 50 restricts the output of the fuel cell 11, so that the generated power (generated current) taken out from the fuel cell 11 is reduced, and the hydrogen tank 10 passes through the first cutoff valve 21. Since the amount of released hydrogen is reduced, as a result, the temperature of the first shut-off valve 21 can be prevented from falling below the performance guarantee temperature B.

  In the above-described embodiment, the case where the ECU 50 limits the generated power (generated current) taken from the fuel cell 11 via the VCU 61 has been described as an example. However, the present invention is not limited to this. The output of the fuel cell 11 may be limited by limiting the power consumption of the motor 62, the compressor 30, and the high voltage battery 63).

  FIG. 6 is a flowchart showing a modified example of the operation of the high-pressure gas supply system, and FIG. 7 is a map showing the relationship between the gas temperature and the gas supply amount. In addition, as means for limiting the gas consumption in the high pressure gas supply system according to the modification, the gas supply amount (hydrogen supply amount) to the fuel cell 11 is changed to a configuration that limits the output of the fuel cell 11. The configuration is limited. Also, steps S201 to S204 shown in FIG. 6 are the same as steps S101 to S104 shown in FIG.

  As a configuration for limiting the amount of gas supplied to the fuel cell 11, for example, the second shutoff valve 24 (see FIG. 1) is used to switch the opening / closing (ON / OFF) timing of the second shutoff valve 24. By controlling, the gas supply amount to the fuel cell 11 can be controlled. The means for limiting the gas supply amount is not limited to the second shutoff valve 24, and may be controlled by providing a variable orifice or the like separately.

  As shown in FIG. 6, when the ECU 50 determines in step S204 that the minimum temperature is equal to or lower than the performance guarantee temperature B (Yes), the ECU 50 returns to the fuel cell 11 based on the gas supply amount restriction map shown in FIG. Gas supply amount (hydrogen supply amount) is limited. The map shown in FIG. 7 shows the relationship between the gas temperature and the amount of gas supplied to the fuel cell 11. For example, the output limit start temperature (predetermined value) A is set to minus 35 ° C., and the performance guarantee temperature ( When the minimum guaranteed seal temperature (B) is set to minus 40 ° C., the gas supply amount is set to decrease as the gas temperature decreases, that is, the limit of the gas supply amount increases. Further, the map shown in FIG. 7 is obtained in advance by experiments, simulations, and the like, and is stored in the ECU 50.

  In step S204, if the ECU 50 determines that the minimum temperature is not equal to or lower than the performance guarantee temperature B (No), the ECU 50 proceeds to step S206 and relaxes the gas supply amount restriction to the fuel cell 11. That is, the ECU 50 controls the second shut-off valve 24 to be normally opened so that the gas supply amount does not limit the gas supply amount.

  In the above-described embodiment, the first cutoff valve 21 has been described as an example of the supply device 20, but the present invention is not limited to this, and the first pressure-reducing valve 22 includes the first cutoff valve 21 and the second cutoff valve. In the case of the high-pressure gas supply system 1 that is less resistant to low temperatures than the valve 24, the second pressure reducing valve 25, etc., for example, the fuel consumption amount (FC output, gas supply) in consideration of the performance guarantee temperature of the first pressure reducing valve 22 Amount) may be limited. Further, not only the first shutoff valve 21 and the first pressure reducing valve 22 but also the second shutoff valve 24 and the second pressure reducing valve 25 may be taken into consideration to limit the fuel consumption.

  In the above-described embodiment, the minimum temperature is determined based on the temperature drop ΔT determined by the gas temperature T1 and the tank pressure P and the environmental temperature T2, but the temperature drop calculated by the gas temperature T1 and the tank pressure P. The minimum temperature may be determined based on ΔT.

  In the above-described embodiment, the case where the pressure sensor 42 is provided in the hydrogen tank 10 has been described as an example. However, the high-pressure gas supply system can obtain a pressure equivalent to the pressure in the hydrogen tank 10. In that case, the pressure sensor 42 may be disposed in the pipe a1.

1 High-pressure gas supply system 10 Hydrogen tank (fuel tank)
DESCRIPTION OF SYMBOLS 11 Fuel cell 20 Supply apparatus 21 1st cutoff valve 24 2nd cutoff valve (fuel consumption control means)
41 Gas temperature sensor (fuel temperature detection means)
42 Pressure sensor (tank pressure detection means)
43 Outside temperature sensor (environmental temperature detection means)
50 ECU (fuel consumption control means)
61 VCU (Fuel consumption control means)

Claims (3)

A fuel tank for supplying fuel accumulated therein to the fuel cell;
A supply device for supplying fuel in the fuel tank to the fuel cell;
Fuel consumption control means for controlling the fuel consumption of the fuel consumed in the fuel cell;
Fuel temperature detecting means for detecting the fuel temperature of the fuel discharged from the fuel tank;
Environmental temperature detection means for detecting the environmental temperature in which the fuel tank is placed;
Tank pressure detecting means for detecting the tank pressure in the fuel tank,
Defines the relationship between the maximum fuel temperature decrease value when the fuel cell with the previous SL tank pressure is continuously operated at full load for each of the environmental temperature,
Sum of the fuel consumption control means detected the time of limiting the fuel consumption amount based on the fuel temperature, before Symbol environmental temperature and the determined from the tank pressure the maximum fuel temperature decrease value and the fuel temperature Is relaxed when the temperature is higher than the performance guarantee temperature of the supply device. The high-pressure gas supply system according to claim 1, wherein the fuel consumption control means limits the output of the fuel cell. The high-pressure gas supply system according to claim 1, wherein the fuel consumption control means limits a supply amount of fuel to the fuel cell.

Images