Hydrogen supply device and hydrogen engine vehicle

Abstract

To restrain pressure fluctuations of hydrogen gas to be supplied to a hydrogen engine.SOLUTION: A hydrogen supply device 30 comprises: a liquid hydrogen pump 32 for pressurizing liquid hydrogen stored in a liquid hydrogen tank 31; a vaporizer 37 for converting the liquid hydrogen discharged from the liquid hydrogen pump 32, into hydrogen gas; a pressure chamber 45 in which the hydrogen gas having flowed out from the vaporizer 37 is packed, and for supplying the packed hydrogen gas to a hydrogen engine 10; and a pump control unit 80. The pump control unit 80 adjusts a discharge flow rate of the liquid hydrogen pump 32 on the basis of a hydrogen flow rate to be supplied to the hydrogen engine 10, and an actual pressure of the pressure chamber 45.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a structure of a hydrogen supply device that supplies hydrogen gas to a hydrogen engine, and to a structure of a hydrogen engine vehicle equipped with a hydrogen supply device. [Background technology]

[0002] Patent Document 1 discloses a hydrogen supply device that includes a liquid hydrogen tank, a hydrogen pump, an evaporator, and a pressurized hydrogen tank. This hydrogen supply device pressurizes liquid hydrogen stored in the liquid hydrogen tank with a hydrogen pump, then vaporizes it in an evaporator to store hydrogen gas in the pressurized hydrogen tank, and supplies the hydrogen gas stored in the pressurized hydrogen tank to a fuel cell.

[0003] Moreover, Patent Document 2 discloses a liquefied gas vaporizer that vaporizes liquid hydrogen by a heat exchanger using helium gas and supplies the vaporized liquid hydrogen to equipment such as a gas turbine.

[0004] Furthermore, Patent Document 3 discloses an engine in which hydrogen gas vaporized in a heat exchanger and air are combusted in a combustion chamber located outside the cylinder, and the combustion gas is caused to flow into the cylinder to drive the piston. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2004-316779 A [Patent Document 2] Patent Publication No. 2021-21433 [Patent Document 3] Special Publication No. 2006-527808 Summary of the Invention [Problem to be solved by the invention]

[0006] In recent years, hydrogen engine vehicles equipped with hydrogen engines that directly burn hydrogen gas instead of gasoline have come into use. Many hydrogen engine vehicles reduce the pressure of high-pressure hydrogen gas stored in a hydrogen gas tank before supplying it to the hydrogen engine. However, the capacity of hydrogen gas that can be stored in a hydrogen gas tank is not very large, and there is a problem that the cruising range of hydrogen engine vehicles is short. For this reason, a method is being considered in which liquid hydrogen stored in a liquid hydrogen tank instead of a hydrogen gas tank is vaporized and supplied to the hydrogen engine.

[0007] Here, because a hydrogen engine vehicle runs solely on the driving force of the hydrogen engine, the amount of hydrogen gas consumed fluctuates more than a fuel cell vehicle equipped with a fuel cell and a driving battery. For this reason, the method of controlling the operation of the hydrogen pump by the pressure of the pressurized hydrogen tank, as in the conventional technology described in Patent Document 1, was sometimes unable to suppress the fluctuations in the pressure of the hydrogen gas supplied to the hydrogen engine.

[0008] Therefore, an object of the present disclosure is to suppress pressure fluctuations in hydrogen gas supplied to a hydrogen engine. [Means for solving the problem]

[0009] The hydrogen supply device of the present disclosure includes a liquid hydrogen pump that pressurizes liquid hydrogen stored in a liquid hydrogen tank, a vaporizer that converts the liquid hydrogen discharged from the liquid hydrogen pump into hydrogen gas, a pressure chamber that is filled with the hydrogen gas flowing out of the vaporizer and supplies the filled hydrogen gas to a hydrogen engine, and a pump control unit that adjusts the discharge flow rate of the liquid hydrogen pump, and the pump control unit adjusts the discharge flow rate of the liquid hydrogen pump based on the hydrogen flow rate supplied to the hydrogen engine and the actual pressure of the pressure chamber. the vaporizer is a heat exchanger that exchanges heat between liquid hydrogen and helium, and is equipped with a heater that exchanges heat between the helium and a cooling oil of the hydrogen engine to heat the helium; Characterized by

[0010] In this way, the hydrogen supply device of the present disclosure adjusts the discharge flow rate of the liquid hydrogen pump based on the hydrogen flow rate supplied to the hydrogen engine and the actual pressure in the pressure chamber, so that even if there is a large change in the hydrogen flow rate, pressure fluctuations in the pressure chamber can be suppressed, and fluctuations in the supply pressure of hydrogen gas supplied to the hydrogen engine can be suppressed. This also makes it possible to use heat from the hydrogen engine to vaporize liquid hydrogen, thereby improving fuel efficiency.

[0011] In the hydrogen supply device of the present disclosure, the pump control unit may adjust the discharge flow rate of the liquid hydrogen pump so that the actual pressure in the pressure chamber becomes a target pressure.

[0012] As a result, the hydrogen supply device of the present disclosure can suppress pressure fluctuations in the pressure chamber, thereby suppressing fluctuations in the supply pressure of hydrogen gas supplied to the hydrogen engine.

[0013] In the hydrogen supply device of the present disclosure, a pressure sensor is provided for detecting the actual pressure in the pressure chamber, and the pump control unit may receive either or both of a target flow rate of hydrogen gas to be supplied to the hydrogen engine and the actual flow rate of hydrogen gas detected by a flow sensor that detects the actual flow rate of hydrogen gas supplied to the hydrogen engine from an engine control unit that adjusts the hydrogen flow rate to be supplied to the hydrogen engine, and adjust the discharge flow rate of the liquid hydrogen pump based on either or both of the target flow rate of hydrogen gas and the actual flow rate of hydrogen gas, and the actual pressure in the pressure chamber detected by the pressure sensor.

[0014] In this way, the hydrogen supply device of the present disclosure adjusts the discharge flow rate of the liquid hydrogen pump based on either or both of the target flow rate of hydrogen gas and the actual flow rate of hydrogen gas input from the engine control unit, so that the discharge flow rate of the liquid hydrogen pump can be adjusted in conjunction with the operation of the hydrogen engine, thereby enabling a quick response to fluctuations in the hydrogen consumption rate of the hydrogen engine and suppressing fluctuations in the pressure of the pressure chamber, thereby suppressing fluctuations in the supply pressure of the hydrogen gas supplied to the hydrogen engine.

[0015] The hydrogen supply device of the present disclosure may include a pressure sensor that detects the actual pressure in the pressure chamber, and a flow sensor that detects the actual flow rate of hydrogen gas supplied to the hydrogen engine, and the pump control unit may adjust the discharge flow rate of the liquid hydrogen pump based on the actual flow rate of hydrogen gas detected by the flow sensor and the actual pressure in the pressure chamber detected by the pressure sensor.

[0016] This enables the hydrogen engine to quickly respond to fluctuations in hydrogen consumption even when there is no input of a target hydrogen gas flow rate or an actual hydrogen gas flow rate from the engine control unit, and suppresses pressure fluctuations in the pressure chamber, thereby suppressing fluctuations in the supply pressure of hydrogen gas supplied to the hydrogen engine.

[0017] In the hydrogen supply device of the present disclosure, the volume of the pressure chamber may be a volume corresponding to 30 to 60 seconds of the maximum hydrogen consumption flow rate of the hydrogen engine.

[0018] This makes it possible to suppress pressure fluctuations in the pressure chamber.

[0021] The hydrogen engine vehicle of the present disclosure includes a hydrogen engine for driving the vehicle, a hydrogen supply device for supplying hydrogen gas to the hydrogen engine, an engine control unit that adjusts the flow rate of hydrogen supplied to the hydrogen engine; and a flow rate sensor that detects the actual flow rate of hydrogen gas supplied to the hydrogen engine. a hydrogen engine vehicle comprising: a liquid hydrogen pump that pressurizes liquid hydrogen stored in a liquid hydrogen tank; a vaporizer that converts the liquid hydrogen discharged from the liquid hydrogen pump into hydrogen gas; and a pressure chamber that is filled with hydrogen gas flowing out from the vaporizer and that supplies the filled hydrogen gas to the hydrogen engine. a pressure sensor for detecting an actual pressure in the pressure chamber; a pump control unit for adjusting the discharge flow rate of the liquid hydrogen pump; the pump control unit is connected to the engine control unit, and either or both of a target flow rate of hydrogen gas to be supplied to the hydrogen engine and the actual flow rate of hydrogen gas are input from the engine control unit, and the pump control unit adjusts the discharge flow rate of the liquid hydrogen pump based on either or both of the target flow rate of hydrogen gas and the actual flow rate of hydrogen gas and the actual pressure of the pressure chamber detected by the pressure sensor, so that the actual pressure of the pressure chamber becomes the target pressure; It is characterized by:

[0024] The hydrogen engine vehicle of the present disclosure may be equipped with an accelerator and an opening sensor that detects the opening of the accelerator, and the engine control unit may calculate the target flow rate of hydrogen gas to be supplied to the hydrogen engine based on the opening of the accelerator detected by the opening sensor, and output the target flow rate to the pump control unit. Effect of the Invention

[0025] The present disclosure can suppress pressure fluctuations of hydrogen gas supplied to a hydrogen engine. [Brief description of the drawings]

[0026] [Figure 1] 1 is a system diagram showing the configuration of a hydrogen engine vehicle according to an embodiment. [Diagram 2] FIG. 2 is a functional block diagram of an engine control unit and a pump control unit of the hydrogen engine vehicle shown in FIG. [Diagram 3] 1 is a system diagram showing a configuration of a hydrogen supply device according to an embodiment. [Figure 4] FIG. 4 is a functional block diagram of a pump control unit of the hydrogen supply device shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, a hydrogen engine vehicle 100 according to an embodiment will be described with reference to the drawings. As shown in Fig. 1, the hydrogen engine vehicle 100 includes a hydrogen engine 10 for driving the vehicle and a hydrogen supply device 30. In Figs. 1 and 3, the thick solid lines indicate the flow paths of liquid, and the double lines indicate the flow paths of gas. Also, the dashed and dotted lines indicate the flow of signals.

[0028] As shown in FIG. 1, a hydrogen engine 10 is a reciprocating internal combustion engine equipped with a plurality of cylinders 11 and pistons 12 that move up and down in the cylinders 11, and has a structure similar to that of a gasoline engine. Note that FIG. 1 illustrates one of the plurality of cylinders 11. An intake port 13 through which air flows into the cylinder 11 and an exhaust port 14 through which combustion gas in the cylinder 11 is exhausted are provided at the top of the cylinder 11. An intake valve 15 and an exhaust valve 16 are attached to the intake port 13 and the exhaust port 14, respectively. An injector 17 that injects hydrogen gas into the cylinder 11 is attached to the upper side of the cylinder 11. A hydrogen gas introduction pipe 23 that introduces hydrogen gas supplied from a hydrogen supply device 30 is connected to the injector 17. The hydrogen gas supplied from the hydrogen gas introduction pipe 23 is injected from the injector 17 into the cylinder 11 and combusted inside the cylinder 11. The combustion gas moves the piston 12 up and down, causing a crankshaft (not shown) connected to the lower end of the piston 12 to rotate.

[0029] The hydrogen engine vehicle 100 is equipped with an accelerator 19, an opening sensor 20, a flow sensor 22, and an engine control unit 70. The accelerator 19 is equipped with an opening sensor 20 that detects the opening, and an opening signal detected by the opening sensor 20 is input to the engine control unit 70. In addition, the hydrogen gas introduction pipe 23 is equipped with a flow sensor 22 that detects the actual flow rate of hydrogen gas flowing into the hydrogen engine 10. A signal of the actual flow rate detected by the flow sensor 22 is input to the engine control unit 70. In addition, the hydrogen engine vehicle 100 is equipped with an oil pump 18 that circulates cooling oil through the hydrogen engine 10. The oil pump 18 operates under the command of the engine control unit 70.

[0030] The engine control unit 70 adjusts the flow rate of hydrogen supplied to the hydrogen engine 10. As shown in Fig. 1, the engine control unit 70 is a computer equipped with a CPU 71, which is a processor for performing information processing, and a memory 72 for storing programs and control data. The engine control unit 70 calculates a target flow rate of hydrogen gas to be supplied to the hydrogen engine 10 based on the opening degree of the accelerator 19 detected by the opening degree sensor 20, and adjusts the operation of the injector 17 to adjust the flow rate of hydrogen gas to the hydrogen engine 10. The engine control unit 70 also adjusts the operation of the oil pump 18. The configuration of the engine control unit 70 will be described in detail later.

[0031] The hydrogen supply device 30 pressurizes and vaporizes liquid hydrogen stored in a liquid hydrogen tank 31, and supplies the hydrogen gas at a supply pressure to the hydrogen engine 10. The hydrogen supply device 30 includes the liquid hydrogen tank 31, a liquid hydrogen pump 32, a vaporizer 37, a pressure chamber 45, a pressure reducing valve 50, a heater 65, and a pump control unit 80.

[0032] The liquid hydrogen tank 31 is a container with a heat-insulating structure that stores cooled liquid hydrogen inside. The internal pressure of the liquid hydrogen tank 31 is approximately the same as atmospheric pressure or slightly higher than atmospheric pressure.

[0033] The liquid hydrogen pump 32 is a reciprocating pump in which an in-tank piston 33 arranged inside the liquid hydrogen tank 31 reciprocates up and down. The liquid hydrogen pump 32 boosts the pressure of the liquid hydrogen stored in the liquid hydrogen tank 31 to a pressure higher than the supply pressure of the hydrogen gas supplied to the hydrogen engine 10. The discharge pressure of the liquid hydrogen pump 32 may be, for example, about twice the supply pressure. A motor 35 and a drive cam 34 that converts the rotational motion of the motor 35 into a reciprocating motion in the up and down direction are arranged outside the liquid hydrogen tank 31. In addition, a suction port that draws in liquid hydrogen and a discharge port that discharges liquid hydrogen are arranged in the casing of the in-tank piston 33, and a liquid hydrogen discharge pipe 36 is connected to the discharge port. The liquid hydrogen discharge pipe 36 extends from inside the liquid hydrogen tank 31 to outside the liquid hydrogen tank 31 and is connected to a vaporizer 37. When motor 35 rotates, drive cam 34 causes in-tank piston 33 to reciprocate up and down, pressurizing the liquid hydrogen stored in liquid hydrogen tank 31 and discharging it from liquid hydrogen discharge pipe 36 to vaporizer 37.

[0034] Vaporizer 37 is a heat exchanger between high-pressure liquid hydrogen discharged from liquid hydrogen pump 32 and heated helium gas, and vaporizes the liquid hydrogen to produce high-pressure hydrogen gas. Vaporizer 37 is composed of a casing 61 through which heated helium gas flows, and a tube 62 attached inside casing 61 and through which high-pressure liquid hydrogen flows.

[0035] Heater 65 is a heat exchanger between the helium gas that has passed through vaporizer 37 and the cooling oil of hydrogen engine 10, and heats the helium gas whose temperature has been reduced after passing through vaporizer 37. Heater 65 is composed of a casing 66 through which helium gas flows, and a tube 67 that is attached inside casing 66 and through which the cooling oil of hydrogen engine 10 flows.

[0036] The casing 61 of the vaporizer 37 and the casing 66 of the heater 65 are connected by a heated gas duct 63 and a return duct 64. A fan 52 is attached to the heated gas duct 63, and when the fan 52 is driven, helium gas circulates between the casing 66 of the heater 65 and the casing 61 of the vaporizer 37. The fan 52 is driven by a command from a pump control unit 80, which will be described later. The cooling oil of the hydrogen engine 10 is pressurized by the oil pump 18, and circulates between the hydrogen engine 10 and the tube 67 of the heater 65 through a supply pipe 68 and a return pipe 69. The oil pump 18 is operated by a command from an engine control unit 70.

[0037] The high-temperature cooling oil of hydrogen engine 10 flows through tube 67 of heater 65 and heats the helium gas. The heated helium gas flows from heated gas duct 63 into casing 61 of vaporizer 37 and exchanges heat with high-pressure, low-temperature liquid hydrogen that has flowed from liquid hydrogen discharge pipe 36 into tube 62 of vaporizer 37. Through the heat exchange, the liquid hydrogen is heated and vaporized, becoming high-pressure hydrogen gas that flows out into high-pressure hydrogen gas supply pipe 38.

[0038] A pressure chamber 45 is connected to the high-pressure hydrogen gas supply pipe 38 via a hydrogen gas filling pipe 39 and a hydrogen gas outflow pipe 41. The hydrogen gas outflow pipe 41 is connected to the downstream side of the hydrogen gas filling pipe 39. A check valve 40 is attached to the hydrogen gas filling pipe 39. In addition, a gate valve 42 is attached to the hydrogen gas outflow pipe 41. A pressure sensor 46 that detects the actual pressure of the pressure chamber 45 is attached to the pressure chamber 45. The capacity of the pressure chamber 45 is the capacity for 30 to 60 seconds of the maximum hydrogen consumption flow rate of the hydrogen engine 10. This makes it possible to suppress pressure fluctuations in the pressure chamber 45 even if the hydrogen consumption rate of the hydrogen engine 10 fluctuates.

[0039] When the hydrogen pressure in the high-pressure hydrogen gas supply pipe 38 is higher than the hydrogen pressure in the pressure chamber 45, the check valve 40 opens and hydrogen gas is filled into the pressure chamber 45 from the hydrogen gas filling pipe 39. On the other hand, when the hydrogen pressure in the high-pressure hydrogen gas supply pipe 38 is lower than the hydrogen pressure in the pressure chamber 45, the hydrogen gas filled in the pressure chamber 45 flows out into the high-pressure hydrogen gas supply pipe 38 through the hydrogen gas outflow pipe 41 and the gate valve 42. The gate valve 42 opens and closes according to commands from a pump control unit 80, which will be described later.

[0040] A pressure reducing valve 50 is provided downstream of the hydrogen gas outflow pipe 41 of the high-pressure hydrogen gas supply pipe 38, which reduces the pressure of the high-pressure hydrogen gas to the supply pressure. The pressure reducing valve 50 operates according to commands from a pump control unit 80, which will be described later. The hydrogen gas reduced to the supply pressure by the pressure reducing valve 50 flows out into a hydrogen gas supply pipe 53 connected downstream of the pressure reducing valve 50. A pressure sensor 51 is attached to the hydrogen gas supply pipe 53, which detects the supply pressure of the hydrogen gas. The hydrogen gas supply pipe 53 is connected to the hydrogen gas introduction pipe 23, and supplies hydrogen gas to the injector 17 of the hydrogen engine 10.

[0041] The pump control unit 80 is a computer equipped with a CPU 81, which is a processor that performs information processing, and a memory 82 that stores programs and control data. The pump control unit 80 is connected to the engine control unit 70, and data is input from the engine control unit 70. In addition, a signal of the actual pressure in the pressure chamber 45 detected by the pressure sensor 46 is input to the pump control unit 80.

[0042] The pump control unit 80 adjusts the pressure reducing valve 50 so that the pressure of the hydrogen gas detected by the pressure sensor 51 is constant. The pump control unit 80 also adjusts the operation of the fan 52. Furthermore, the pump control unit 80 adjusts the discharge flow rate of the liquid hydrogen pump 32 based on the flow rate of hydrogen supplied to the hydrogen engine 10 and the actual pressure of the pressure chamber 45 detected by the pressure sensor 46.

[0043] Next, the engine control unit 70 and the pump control unit 80 will be described in detail with reference to FIG.

[0044] The engine control unit 70 includes two functional blocks: a target flow rate calculation section 75 and an injector PID control section 76. Each functional block can be realized by the CPU 71 executing a program stored in the memory 72.

[0045] The target flow rate calculation section 75 of the engine control unit 70 calculates a target flow rate of hydrogen gas to be supplied to the hydrogen engine 10 based on the opening of the accelerator 19 input from the opening sensor 20. The target flow rate may be calculated, for example, as a flow rate proportional to the opening of the accelerator 19, or may be calculated by referring to a map of the opening and the target flow rate stored in the memory 72. Note that the target flow rate may be calculated taking into account, for example, the speed of the hydrogen engine vehicle 100 and the rotation speed of the hydrogen engine 10 in addition to the opening of the accelerator 19. The target flow rate calculation section 75 outputs the calculated target flow rate to the injector PID control section 76 and also to the pump PID control section 86 of the pump control unit 80.

[0046] The injector PID control unit 76 calculates an injector drive command by PID control based on the difference between the target flow rate of hydrogen gas input from the target flow rate calculation unit 75 and the actual flow rate of hydrogen gas detected by the flow sensor 22, and outputs the calculated injector drive command to the injector 17. The injector 17 operates according to the drive command from the injector PID control unit 76. The injector PID control unit 76 also outputs the actual flow rate of hydrogen gas input from the flow sensor 22 to a pump PID control unit 86 of the pump control unit 80.

[0047] The pump control unit 80 includes three functional blocks: a pressure feedback control unit 85, a pump PID control unit 86, and an adder 87. Each functional block is realized by the CPU 81 executing a program stored in the memory 82.

[0048] The hydrogen supply device 30 may generate hydrogen gas at a flow rate equal to the actual flow rate of hydrogen gas consumed by the hydrogen engine 10. Since the amount of hydrogen gas generated is proportional to the flow rate of liquid hydrogen discharged from the liquid hydrogen pump 32, the flow rate of liquid hydrogen discharged from the liquid hydrogen pump 32 may be controlled to a flow rate proportional to the actual flow rate of hydrogen gas consumed by the hydrogen engine 10. However, when the flow rate of hydrogen gas generated by the hydrogen supply device 30 is smaller than the flow rate of hydrogen gas consumed by the hydrogen engine 10, the actual pressure of the pressure chamber 45 decreases. Conversely, when the flow rate of hydrogen gas generated by the hydrogen supply device 30 is greater than the flow rate of hydrogen gas consumed by the hydrogen engine 10, the actual pressure of the pressure chamber 45 increases. When the actual pressure of the pressure chamber 45 fluctuates, the supply pressure of hydrogen gas downstream of the pressure reducing valve 50 fluctuates. Also, when the actual pressure of the pressure chamber 45 becomes lower than the supply pressure, hydrogen gas cannot be supplied to the hydrogen engine 10.

[0049] Therefore, the pump control unit 80 calculates a PID command value by the pump PID control unit 86 for adjusting the rotation speed of the motor 35 of the liquid hydrogen pump 32 so that the flow rate of liquid hydrogen discharged from the liquid hydrogen pump 32 corresponds to the flow rate of hydrogen gas supplied to the hydrogen engine 10. In addition, the pressure feedback control unit 85 calculates a pressure feedback command value for adjusting the rotation speed of the motor 35 of the liquid hydrogen pump 32 so as to suppress fluctuations in the actual pressure in the pressure chamber 45. Then, the adder 87 adds the PID command value and the pressure feedback command value to generate a motor rotation speed command to adjust the rotation speed of the motor 35. In this way, fluctuations in the actual pressure in the pressure chamber 45 are suppressed, and fluctuations in the supply pressure of hydrogen gas are suppressed.

[0050] The pump PID control unit 86 outputs a PID command value for the rotation speed of the motor 35 of the liquid hydrogen pump 32 based on the difference between the target flow rate and the actual flow rate of hydrogen gas input from the engine control unit 70. This PID command value is calculated based on the difference between the target value and the actual flow rate of hydrogen gas, which is the same as that of the injector PID control unit 76, and therefore is a command value synchronized with the injector drive command. Therefore, the PID command value can make the flow rate of liquid hydrogen discharged from the liquid hydrogen pump 32 a flow rate corresponding to the flow rate of hydrogen gas supplied to the hydrogen engine 10. As a result, even if the opening degree of the accelerator 19 fluctuates and the flow rate of hydrogen gas consumed by the hydrogen engine 10 fluctuates, hydrogen gas can be generated in synchronization with the fluctuation in the flow rate of hydrogen gas consumed by the hydrogen engine 10, and the fluctuation in the actual pressure of the pressure chamber 45 can be suppressed, thereby suppressing the fluctuation in the supply pressure supplied to the hydrogen engine 10.

[0051] The pressure feedback control unit 85 outputs a pressure feedback control command value based on the difference between the target pressure stored in the memory 72 and the actual pressure in the pressure chamber 45 detected by the pressure sensor 46. The target pressure can be determined appropriately as long as it is higher than the supply pressure to the hydrogen engine 10 and lower than the upper limit pressure. The pressure feedback command value is a command value that increases the rotation speed of the motor 35 of the liquid hydrogen pump 32 to increase the discharge flow rate when the actual pressure in the pressure chamber 45 falls below the target pressure, and conversely, decreases the rotation speed of the motor 35 of the liquid hydrogen pump 32 to decrease the discharge flow rate when the actual pressure in the pressure chamber 45 becomes higher than the target pressure.

[0052] The adder 87 adds the PID command value and the pressure feedback command value to generate a rotation speed command for the motor 35. When adding, the two command values ​​may be simply added together, or may be weighted and added together. For example, when the fluctuation in the amount of hydrogen consumed by the hydrogen engine 10 is not very large, the weight of the pressure feedback command value may be made greater than the weight of the PID command value. Conversely, when the fluctuation in the amount of hydrogen consumed by the hydrogen engine 10 is large, the weight of the PID command value may be made greater to improve responsiveness.

[0053] In this way, the PID command value and the pressure feedback command value are added to generate a rotation speed command for the motor 35, and the rotation speed of the motor 35 of the liquid hydrogen pump 32 is adjusted to adjust the discharge flow rate of the liquid hydrogen pump 32, thereby suppressing fluctuations in the actual pressure in the pressure chamber 45 and thereby suppressing fluctuations in the supply pressure of hydrogen gas.

[0054] In the above explanation, the pump control unit 80 is explained as receiving the target flow rate of hydrogen gas and the actual flow rate of hydrogen gas detected by the flow sensor 22 from the engine control unit 70, but this is not limited to the above, and the pump control unit 80 may be configured to receive a signal of the actual flow rate of hydrogen gas directly from the flow sensor 22 without going through the engine control unit 70.

[0055] In the above description, the pump control unit 80 is described as including a pump PID control section 86 that outputs a PID command value for the rotation speed of the motor 35 of the liquid hydrogen pump 32 based on the difference between the target flow rate and the actual flow rate of hydrogen gas input from the engine control unit 70, but this is not limited to the above. For example, based on one input of the target flow rate of hydrogen gas or the actual flow rate of hydrogen gas from the engine control unit 70, a proportional command value may be calculated by proportional control as in the hydrogen supply device 130 shown in Figures 3 and 4, and a rotation speed command for the motor 35 may be generated based on this and a pressure feedback command value.

[0056] 3 and 4, a hydrogen supply device 130 having a different configuration from the hydrogen supply device 30 described above will be described. The same components as those in the hydrogen supply device 30 described above are given the same reference numerals and the description thereof will be omitted.

[0057] 3, the hydrogen supply device 130 is equipped with a flow rate sensor 92 that is attached to the hydrogen gas supply pipe 53 and detects the flow rate of hydrogen gas supplied to the hydrogen engine 10. A signal of the flow rate detected by the flow rate sensor 92 is input to a pump control unit 180. The pump control unit 180 is a computer that includes a CPU 181, which is a processor that performs information processing, and a memory 182 that stores programs and control data. Unlike the pump control unit 80 of the hydrogen supply device 30 of the embodiment described above, the pump control unit 180 is not connected to the engine control unit 70.

[0058] 4, the pump control unit 180 includes a pump proportional control unit 88 instead of the pump PID control unit 86 of the pump control unit 80 described above. The pump proportional control unit 88 calculates a proportional command value by multiplying the actual flow rate of hydrogen gas detected by the flow sensor 92 by a proportional constant. The proportional command value enables the hydrogen supply device 130 to generate hydrogen gas in accordance with fluctuations in the flow rate of hydrogen gas consumed by the hydrogen engine 10, and, like the hydrogen supply device 30 described above, can suppress fluctuations in the actual pressure of the pressure chamber 45 and thereby suppress fluctuations in the supply pressure of hydrogen gas. [Explanation of symbols]

[0059] 10 hydrogen engine, 11 cylinder, 12 piston, 13 intake port, 14 exhaust port, 15 intake valve, 16 exhaust valve, 17 injector, 18 oil pump, 19 accelerator, 20 opening sensor, 22, 92 flow sensor, 23 hydrogen gas inlet pipe, 30, 130 hydrogen supply device, 31 liquid hydrogen tank, 32 liquid hydrogen pump, 33 in-tank piston, 34 drive cam, 35 motor, 36 liquid hydrogen discharge pipe, 37 carburetor, 38 high pressure hydrogen gas supply pipe, 39 hydrogen gas filling pipe, 40 check valve, 41 hydrogen gas outflow pipe, 42 gate valve, 45 pressure chamber, 46 pressure sensor, 48 recirculation valve, 50 pressure reducing valve, 51 pressure sensor, 52 fan, 53 hydrogen gas supply pipe, 61, 66 casing, 62, 67 tube, 63 Heated gas duct, 64 return duct, 65 heater, 68 supply pipe, 69 return pipe, 70 engine control unit, 71, 81, 181 CPU, 72, 82, 182 memory, 75 target flow rate calculation unit, 76 injector PID control unit, 80, 180 pump control unit, 85 pressure feedback control unit, 86 pump PID control unit, 87 adder, 88 pump proportional control unit, 100 hydrogen engine vehicle.

Claims

1. A hydrogen supply device, comprising: a liquid hydrogen pump that pressurizes the liquid hydrogen stored in the liquid hydrogen tank; a vaporizer that converts the liquid hydrogen discharged from the liquid hydrogen pump into hydrogen gas; a pressure chamber which is filled with hydrogen gas flowing out from the carburetor and supplies the filled hydrogen gas to a hydrogen engine; a pump control unit that adjusts the discharge flow rate of the liquid hydrogen pump; The pump control unit adjusts the discharge flow rate of the liquid hydrogen pump based on the hydrogen flow rate supplied to the hydrogen engine and the actual pressure of the pressure chamber; the vaporizer is a heat exchanger that exchanges heat between liquid hydrogen and helium, a heater for exchanging heat between helium and the cooling oil of the hydrogen engine to heat the helium; A hydrogen supply device comprising:

2. 2. The hydrogen supply device according to claim 1, the pump control unit adjusts the discharge flow rate of the liquid hydrogen pump so that the actual pressure in the pressure chamber becomes a target pressure; A hydrogen supply device comprising:

3. The hydrogen supply device according to claim 2, a pressure sensor for detecting the actual pressure in the pressure chamber; The pump control unit Either or both of a target flow rate of hydrogen gas to be supplied to the hydrogen engine and an actual flow rate of hydrogen gas detected by a flow sensor that detects an actual flow rate of hydrogen gas to be supplied to the hydrogen engine are input from an engine control unit that adjusts the hydrogen flow rate to be supplied to the hydrogen engine, adjusting the discharge flow rate of the liquid hydrogen pump based on either or both of the target flow rate of hydrogen gas and the actual flow rate of hydrogen gas, and the actual pressure of the pressure chamber detected by the pressure sensor; A hydrogen supply device comprising:

4. The hydrogen supply device according to claim 2, a pressure sensor for detecting the actual pressure in the pressure chamber; a flow rate sensor for detecting an actual flow rate of hydrogen gas supplied to the hydrogen engine; the pump control unit adjusts the discharge flow rate of the liquid hydrogen pump based on the actual flow rate of hydrogen gas detected by the flow rate sensor and the actual pressure of the pressure chamber detected by the pressure sensor; A hydrogen supply device comprising:

5. The hydrogen supply device according to any one of claims 1 to 4, The volume of the pressure chamber is a volume from 30 seconds to 60 seconds of a maximum hydrogen consumption flow rate of the hydrogen engine; A hydrogen supply device comprising:

6. A hydrogen engine for driving a vehicle; A hydrogen supply device for supplying hydrogen gas to the hydrogen engine; an engine control unit that adjusts the flow rate of hydrogen supplied to the hydrogen engine; A hydrogen engine vehicle comprising: a flow rate sensor for detecting an actual flow rate of hydrogen gas supplied to the hydrogen engine; The hydrogen supply device is a liquid hydrogen pump that pressurizes the liquid hydrogen stored in the liquid hydrogen tank; a vaporizer that converts the liquid hydrogen discharged from the liquid hydrogen pump into hydrogen gas; a pressure chamber which is filled with hydrogen gas flowing out from the carburetor and supplies the filled hydrogen gas to the hydrogen engine; a pressure sensor for detecting an actual pressure in the pressure chamber; a pump control unit for adjusting the discharge flow rate of the liquid hydrogen pump; the pump control unit is connected to the engine control unit, and either or both of a target flow rate of hydrogen gas to be supplied to the hydrogen engine and the actual flow rate of hydrogen gas are input from the engine control unit, and the pump control unit adjusts the discharge flow rate of the liquid hydrogen pump based on either or both of the target flow rate of hydrogen gas and the actual flow rate of hydrogen gas and the actual pressure of the pressure chamber detected by the pressure sensor, so that the actual pressure of the pressure chamber becomes the target pressure; A hydrogen engine vehicle characterized by:

7. 7. A hydrogen engine vehicle according to claim 6, Axel and an opening sensor for detecting an opening of the accelerator, the engine control unit calculates the target flow rate of hydrogen gas to be supplied to the hydrogen engine based on the accelerator opening detected by the opening sensor, and outputs the target flow rate to the pump control unit; A hydrogen engine vehicle characterized by:

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