阅读说明：本技术 燃料电池混合动力汽车的气体置换系统及其控制方法 (Gas replacement system of fuel cell hybrid electric vehicle and control method thereof ) 是由 王波 吴星成 陈明 王子剑 贺翀 于 2021-07-09 设计创作，主要内容包括：本发明公开了一种燃料电池混合动力汽车的气体置换系统及其控制方法,气体置换系统包括加气组件、氢瓶、氢瓶电磁阀、压力传感器、减压阀、手动排空阀,还包括置换开关、HMS氢系统控制器、上位机、蓄电池,HMS氢系统控制器与蓄电池硬线连接且置换开关设置于HMS氢系统控制器与蓄电池之间,HMS氢系统控制器与氢瓶电磁阀电性连接,所述HMS氢系统控制器与压力传感器与电性连接,上位机与HMS氢系统控制器电性连接。本发明独立设置置换开关控制HMS氢系统控制器的唤醒和休眠,优化了参与置换模式的控制器数量,降低能耗,实现氢系统控制器HMS对氢瓶瓶阀启闭的单独控制,避免对气体置换造成干扰。(The invention discloses a gas replacement system of a fuel cell hybrid electric vehicle and a control method thereof, wherein the gas replacement system comprises a gas filling assembly, a hydrogen bottle electromagnetic valve, a pressure sensor, a pressure reducing valve, a manual emptying valve, a replacement switch, a HMS hydrogen system controller, an upper computer and a storage battery, the HMS hydrogen system controller is in hard-line connection with the storage battery, the replacement switch is arranged between the HMS hydrogen system controller and the storage battery, the HMS hydrogen system controller is electrically connected with the hydrogen bottle electromagnetic valve, the HMS hydrogen system controller is electrically connected with the pressure sensor, and the upper computer is electrically connected with the HMS hydrogen system controller. The invention independently sets the replacement switch to control the awakening and dormancy of the HMS hydrogen system controller, optimizes the number of controllers participating in the replacement mode, reduces energy consumption, realizes the independent control of the hydrogen system controller HMS on the opening and closing of the hydrogen bottle valve, and avoids the interference on gas replacement.)

1. The gas replacement system of the fuel cell hybrid electric vehicle is characterized by comprising a gas filling assembly, a hydrogen bottle (1), a hydrogen bottle electromagnetic valve (2), a pressure sensor (3), a pressure reducing valve (4) and a manual emptying valve (5) which are connected through pipelines, wherein the gas filling assembly is connected with the inlet end of the hydrogen bottle (1) and used for supplying gas, and the outlet end of the hydrogen bottle (1) is sequentially connected with the hydrogen bottle electromagnetic valve (2), the pressure sensor (3), the pressure reducing valve (4) and the manual emptying valve (5) along the gas flow direction and then is communicated with the outside of the vehicle;

the system is characterized by further comprising a replacement switch (11), an HMS hydrogen system controller (12), an upper computer (13) and a storage battery (14), wherein the HMS hydrogen system controller (12) is in hard-line connection with the storage battery (14), the replacement switch (11) is arranged between the HMS hydrogen system controller (12) and the storage battery (14) and used for controlling on-off, the HMS hydrogen system controller (12) is electrically connected with a hydrogen bottle electromagnetic valve (2) and used for controlling on-off of the HMS hydrogen system controller, the HMS hydrogen system controller (12) is electrically connected with a pressure sensor (3) and used for distributing power to the pressure sensor (3) and feeding back exhaust pressure to the HMS hydrogen system controller (12) in real time through the pressure sensor (3), and the upper computer (13) is electrically connected with the HMS hydrogen system controller (12) and used for displaying and monitoring exhaust pressure.

2. The gas replacement system of the fuel cell hybrid electric vehicle according to claim 1, wherein the gas filling assembly comprises a nitrogen source (7), a hydrogen source (8) and a gas filling device (9), the gas filling device (9) is provided with two gas inlets respectively communicated with the nitrogen source (7) and the hydrogen source (8), the outlet end of the gas filling device (9) is sequentially provided with a pressure gauge (15) and a hydrogenation port (10) along the gas flow direction, and the hydrogenation port (10) is connected with the inlet end of the hydrogen cylinder (1).

3. The gas replacement system for a fuel cell hybrid vehicle according to claim 2, wherein a check valve (6) that allows only gas to flow toward the inlet end of the hydrogen cylinder (1) is provided between the hydrogen addition port (10) and the hydrogen cylinder (1).

4. The gas replacement system for a fuel cell hybrid vehicle according to claim 2, wherein the nitrogen gas source (7), the hydrogen gas source (8), and the gas filling device (9) are each provided with a manual valve at an outlet end.

5. The gas replacement system of a fuel cell hybrid vehicle according to claim 1, wherein an electrical input terminal of the replacement switch (11) is hard-wired to the battery (14), an electrical output terminal thereof is hard-wired to the HMS hydrogen system controller (12), the replacement switch (11) has an ON position and an OFF position, the replacement switch (11) is in the ON position, and the battery (14) and the hydrogen system controller (12) are connected to each other, and the replacement switch (11) is in the OFF position, and the HMS hydrogen system controller (12) and the battery (14) are disconnected from each other.

6. A gas replacement control method for a fuel cell hybrid vehicle, characterized by comprising the steps of:

step one, confirming that a key of the whole vehicle is in an OFF gear;

step two, hydrogen cylinder exhaust

a. The HMS hydrogen system controller (12) and the storage battery (14) are conducted by operating the replacement switch (11), the whole vehicle enters a replacement mode, and the HMS hydrogen system controller (12) completes awakening after receiving a conduction signal sent by the storage battery (14);

the method comprises the following steps that (b) a hydrogen bottle electromagnetic valve (2) communicated with the outlet end of a hydrogen bottle (1) is controlled to be opened by a HMS hydrogen system controller (12), a manual evacuation valve (5) behind the hydrogen bottle electromagnetic valve (2) is operated to exhaust gas in the hydrogen bottle (1) out of a vehicle, the exhaust pressure of the hydrogen bottle (1) is monitored in real time, the opening degree of the manual evacuation valve (5) is adjusted, and the manual evacuation valve (5) is operated to stop the exhaust of the hydrogen bottle (1) when the exhaust pressure reaches a preset exhaust pressure P2;

c. the HMS hydrogen system controller (12) and the storage battery (14) are disconnected by operating the replacement switch (11), the HMS hydrogen system controller (12) controls the hydrogen bottle electromagnetic valve (2) to be closed after receiving a disconnection signal sent by the storage battery (14), and the HMS hydrogen system controller (12) enters a dormant state;

step three, gas replacement

Filling nitrogen into the hydrogen bottle (1) to a preset inflation pressure P1, repeating the step two to perform nitrogen replacement for one time, and repeating the nitrogen replacement for multiple times until the preset nitrogen replacement times N1 are reached; and (3) filling hydrogen into the hydrogen bottle (1) to a preset inflation pressure P1, repeating the step two to perform primary hydrogen replacement, repeating the hydrogen replacement for multiple times until the preset hydrogen replacement times N2 are reached, finishing the replacement process of the whole vehicle, and exiting the replacement mode.

7. The gas replacement control method for a fuel cell hybrid vehicle according to claim 6, wherein in the third step, the step of filling nitrogen gas into the hydrogen cylinder (1) to the preset inflation pressure P1 includes: manually opening a nitrogen source (7) and an air adding device (9), leading nitrogen in the nitrogen source (7) to a hydrogen bottle (1) through the air adding device (9) until the pressure in the hydrogen bottle (1) reaches a preset inflation pressure P1, and manually closing the nitrogen source (7) and the air adding device (9);

the hydrogen gas is filled into the hydrogen bottle (1) specifically as follows: the hydrogen source (8) and the gas filling device (9) for supplying hydrogen are manually opened, the hydrogen in the hydrogen source (8) is led to the hydrogen cylinder (1) through the gas filling device (9) until the pressure in the hydrogen cylinder (1) reaches the preset filling pressure P1, and then the hydrogen source (8) and the gas filling device (9) are manually closed.

8. The gas replacement control method for a fuel cell hybrid vehicle according to claim 7, wherein the pressure in the hydrogen cylinder (1) is obtained by observing a pressure gauge (15) provided at an outlet end of the gas adding device (9).

9. The gas replacement control method for a fuel cell hybrid vehicle according to claim 6, wherein in step b, the real-time monitoring of the exhaust pressure of the hydrogen tank (1) and the adjustment of the opening of the manual purge valve (5) are specifically as follows:

The HMS hydrogen system controller (12) distributes power to the pressure sensor (3), the pressure sensor (3) starts to work and feeds back exhaust pressure to the HMS hydrogen system controller (12) in real time, the upper computer (13) obtains the exhaust pressure from the HMS hydrogen system controller (12) and displays the exhaust pressure in real time, the exhaust pressure displayed by the upper computer (13) is observed, and the opening of the manual emptying valve (5) is adjusted according to the difference between the exhaust pressure and a preset exhaust pressure P2.

10. The gas replacement control method for a fuel cell hybrid vehicle according to claim 6, wherein the replacement switch (11) is provided with an ON position and an OFF position, and in step two, in step a, the replacement switch (11) is operated to be positioned at the ON position to conduct between the HMS hydrogen system controller (12) and the battery (14); in step two, the replacement switch (11) is operated to be positioned in an OFF position to disconnect the HMS hydrogen system controller (12) and the storage battery (14).

Technical Field

The invention relates to a fuel cell automobile, in particular to a gas replacement system of a fuel cell hybrid electric vehicle and a control method thereof.

Background

In a fuel cell hybrid vehicle, because a helium gas or a helium-nitrogen mixed gas (5% helium gas + 95% nitrogen gas) is generally used for gas tightness test before a vehicle-mounted high-pressure (35MPa/70MPa) hydrogen bottle leaves a factory, a little test gas remains on the hydrogen bottle, in order to exhaust the residual gas as much as possible, the gas replacement work in the hydrogen bottle must be completed before the fuel cell complete vehicle assembly is subjected to first hydrogenation, the replacement of the gas tightness residual gas is completed by firstly charging nitrogen gas and then exhausting the nitrogen gas, at the moment, the residual gas in the hydrogen bottle is mainly nitrogen gas, then the nitrogen gas replacement is completed by charging hydrogen gas and exhausting the nitrogen gas for a plurality of times, and the hydrogen gas meeting the purity requirement in the hydrogen bottle is ensured. The replacement process needs to open and close the cylinder valve of the gas cylinder, and the opening and closing of the cylinder valve are controlled by a hydrogen system controller (HMS). And meanwhile, the pressure state in the hydrogen cylinder is monitored by utilizing an upper computer (an external computer), so that the pressure change of the hydrogen cylinder is ensured within a controllable range.

Replacement control of traditional fuel cell hybrid vehicle, need whole car key ON shelves go ON after going ON, can't awaken hydrogen system controller alone and operate, and normal key ON keeps off, can awaken most controllers (such as whole car controller VCU, fuel system controller FCU, power battery controller BMS etc.) ON the car, lead to 12V battery load to increase, there is the battery insufficient voltage risk in long-time replacement operation, each controller awakens up simultaneously, because mutual signal interaction, the individual control that hydrogen system controller HMS opened and close hydrogen bottle valve when probably disturbing the replacement. How to realize gas replacement on the premise of meeting basic requirements, reducing modules participating in control as much as possible, simplifying a control system, improving control efficiency and reducing energy consumption is a technical problem to be solved urgently for fuel cell hybrid electric vehicles.

Therefore, a gas replacement system and a control method thereof are needed to be developed, wherein the gas replacement system is simple in structure and convenient to operate, and gas replacement can be performed without electrifying an ON shift of a key of the whole vehicle.

Disclosure of Invention

The present invention aims to solve the above-mentioned drawbacks of the background art, and provides a gas replacement system and a control method thereof, which has a simple structure and is convenient to operate, and can perform gas replacement without powering ON an ON shift of a key of a vehicle.

The technical scheme of the invention is as follows: the gas replacement system of the fuel cell hybrid electric vehicle is characterized by comprising a gas filling assembly, a hydrogen bottle electromagnetic valve, a pressure sensor, a pressure reducing valve and a manual emptying valve which are connected through a pipeline, wherein the gas filling assembly is connected with the inlet end of the hydrogen bottle and used for supplying gas, and the outlet end of the hydrogen bottle is sequentially connected with the hydrogen bottle electromagnetic valve, the pressure sensor, the pressure reducing valve and the manual emptying valve along the gas flow direction and then is communicated with the outside of the vehicle;

still include change over switch, HMS hydrogen system controller, host computer, battery, HMS hydrogen system controller and battery hardwired, change over switch sets up and is used for controlling the break-make between HMS hydrogen system controller and battery, HMS hydrogen system controller and hydrogen bottle solenoid valve electric connection are used for controlling it to open and close, HMS hydrogen system controller and pressure sensor and electric connection are used for to pressure sensor distribution power just pressure sensor feeds back the exhaust pressure to HMS hydrogen system controller real time, host computer and HMS hydrogen system controller electric connection are used for showing, control the exhaust pressure.

Preferably, the gas filling assembly comprises a nitrogen source, a hydrogen source and gas filling equipment, the gas filling equipment is provided with two gas inlets which are respectively communicated with the nitrogen source and the hydrogen source, the outlet end of the gas filling equipment is sequentially provided with a pressure gauge and a hydrogenation port along the gas flow direction, and the hydrogenation port is connected with the inlet end of the hydrogen cylinder.

Furthermore, a one-way valve which only allows gas to flow towards the inlet end of the hydrogen bottle is arranged between the hydrogenation port and the hydrogen bottle.

Furthermore, the nitrogen source, the hydrogen source and the gas filling equipment are all provided with manual valves at outlet ends.

Preferably, the electrical input end of the replacement switch is in hard-line connection with the storage battery, the electrical output end of the replacement switch is in hard-line connection with the HMS hydrogen system controller, the replacement switch is provided with an ON gear and an OFF gear, the storage battery and the hydrogen system controller are connected when the replacement switch is located at the ON gear, and the HMS hydrogen system controller and the storage battery are disconnected when the replacement switch is located at the OFF gear.

The invention also provides a gas replacement control method of the fuel cell hybrid electric vehicle, which comprises the following steps:

step one, confirming that a key of the whole vehicle is in an OFF gear;

step two, hydrogen cylinder exhaust

a. The HMS hydrogen system controller is operated to conduct the HMS hydrogen system controller and the storage battery, the whole vehicle enters a replacement mode, and the HMS hydrogen system controller is awakened after receiving a conduction signal sent by the storage battery;

Controlling a hydrogen bottle electromagnetic valve communicated with the outlet end of the hydrogen bottle to open by an HMS hydrogen system controller, operating a manual emptying valve behind the hydrogen bottle electromagnetic valve to discharge gas in the hydrogen bottle out of the vehicle, monitoring the exhaust pressure of the hydrogen bottle in real time and adjusting the opening of the manual emptying valve, and operating the manual emptying valve to stop the exhaust of the hydrogen bottle when the exhaust pressure reaches a preset exhaust pressure P2;

c. the HMS hydrogen system controller is controlled to be in a dormant state after receiving a disconnection signal sent by the storage battery;

step three, gas replacement

Filling nitrogen into the hydrogen bottle to a preset inflation pressure P1, repeating the step two to perform nitrogen replacement for one time, and repeating the nitrogen replacement for multiple times until the preset nitrogen replacement times N1 are reached; and (4) repeating the step two after the hydrogen is filled into the hydrogen bottle to the preset inflation pressure P1 to form hydrogen replacement for one time, repeating the hydrogen replacement for multiple times until the preset hydrogen replacement times N2 are reached, finishing the replacement process of the whole vehicle, and exiting the replacement mode.

Preferably, in the third step, the step of filling the hydrogen bottle with nitrogen to the preset inflation pressure P1 specifically comprises: manually opening a nitrogen source and gas filling equipment to lead nitrogen in the nitrogen source to a hydrogen cylinder through the gas filling equipment until the pressure in the hydrogen cylinder reaches a preset inflation pressure P1, and manually closing the nitrogen source and the gas filling equipment;

The hydrogen filling into the hydrogen bottle specifically comprises the following steps: and manually opening a hydrogen source and a gas filling device for supplying hydrogen, leading the hydrogen in the hydrogen source to a hydrogen cylinder through the gas filling device until the pressure in the hydrogen cylinder reaches a preset inflation pressure P1, and manually closing the hydrogen source and the gas filling device.

Further, the pressure in the hydrogen bottle is obtained by observing a pressure gauge arranged at the outlet end of the gas filling equipment.

Preferably, in step b of the second step, the monitoring of the exhaust pressure of the hydrogen cylinder in real time and the adjustment of the opening of the manual purge valve specifically include:

the HMS hydrogen system controller distributes power to the pressure sensor, the pressure sensor starts working and feeds back exhaust pressure to the HMS hydrogen system controller in real time, the upper computer obtains the exhaust pressure from the HMS hydrogen system controller and displays the exhaust pressure in real time, the exhaust pressure displayed by the upper computer is observed, and the opening of the manual emptying valve is adjusted according to the difference value between the exhaust pressure and the preset exhaust pressure P2.

Furthermore, the replacement switch is provided with an ON gear and an OFF gear, and in step two, the replacement switch is operated to be positioned at the ON gear to conduct the HMS hydrogen system controller 12 and the storage battery 14; in step two, the HMS hydrogen system controller and the battery are disconnected from each other by operating the replacement switch to the OFF position.

The invention has the beneficial effects that:

1. the replacement switch is independently arranged to control the awakening and sleeping of the HMS hydrogen system controller, the number of controllers participating in a replacement mode is optimized, the participation of electric devices is reduced as far as possible, the energy consumption is reduced, the hydrogen system controller HMS independently controls the opening and closing of the hydrogen bottle valve, and the interference on gas replacement is avoided.

2. The hydrogen bottle is inflated by manual operation, and only one necessary HMS hydrogen system controller is awakened during exhaust, so that the replacement control logic is simplified, and the efficiency is improved.

3. Reduce the battery load, practice thrift the energy consumption, avoid battery insufficient voltage, the replacement switch of independent setting makes the function definition more clear and definite, and the operation is more pointed, has avoided the emergence of maloperation, and the host computer monitors the pressure state in the bottle, ensures that hydrogen bottle pressure variation is within controllable range

Drawings

FIG. 1 is a block diagram of a gas exchange system according to the present invention

FIG. 2 is a flow chart of the gas replacement control method of the present invention

Wherein: 1-hydrogen cylinder 2-hydrogen cylinder electromagnetic valve 3-pressure sensor 4-pressure reducing valve 5-manual emptying valve 6-one-way valve 7-nitrogen source 8-hydrogen source 9-gas filling equipment 10-hydrogenation port 11-replacement switch 12-HMS hydrogen system controller 13-upper computer 14-storage battery 15-pressure gauge.

Detailed Description

The invention is described in further detail below with reference to the figures and the specific embodiments.

As shown in fig. 1, the gas replacement system of a fuel cell hybrid electric vehicle provided by the invention comprises a gas filling assembly, a hydrogen bottle 1, a hydrogen bottle electromagnetic valve 2, a pressure sensor 3, a pressure reducing valve 4 and a manual emptying valve 5 which are connected by pipelines, wherein the gas filling assembly is connected with the inlet end of the hydrogen bottle 1 and used for supplying helium and hydrogen, and the outlet end of the hydrogen bottle 1 is sequentially connected with the hydrogen bottle electromagnetic valve 2, the pressure sensor 3, the pressure reducing valve 4 and the manual emptying valve 5 along the gas flow direction and then led out of the vehicle; the gas filling assembly comprises a nitrogen source 7, a hydrogen source 8 and a gas filling device 9, wherein the gas filling device 9 is provided with two gas inlets which are respectively communicated with the nitrogen source 7 and the hydrogen source 8, the outlet end of the gas filling device 9 is sequentially provided with a pressure gauge 15 and a hydrogenation port 10 along the gas flow direction, the hydrogenation port 10 is connected with the inlet end of the hydrogen cylinder 1, and a check valve 6 which only allows gas to flow towards the inlet end of the hydrogen cylinder 1 is arranged between the hydrogenation port 10 and the hydrogen cylinder 1.

According to the invention, the gas flow direction is from front to back, the nitrogen source 7, the hydrogen source 8 and the gas filling equipment 9 are respectively provided with a manual valve at the outlet end, a pressure gauge 15 can display the internal pressure of the hydrogen cylinder 1, the pressure gauge 15 is arranged behind the manual valve of the gas filling equipment 9, and the pressure gauge 15 is positioned between the manual valve of the gas filling equipment 9 and the hydrogenation port 10.

The gas replacement system further comprises a replacement switch 11, a HMS hydrogen system controller 12, an upper computer 13 and a storage battery 14, wherein the HMS hydrogen system controller 12 is in hard-line connection with the storage battery 14, the replacement switch 11 is arranged between the HMS hydrogen system controller 12 and the storage battery 14 and used for controlling the on-off of the HMS hydrogen system controller 12 and the storage battery 14, the HMS hydrogen system controller 12 is electrically connected with the hydrogen bottle electromagnetic valve 2 and used for controlling the on-off of the hydrogen bottle electromagnetic valve 2, the HMS hydrogen system controller 12 is electrically connected with the pressure sensor 3 and used for distributing power to the pressure sensor 3, the pressure sensor 3 feeds back exhaust pressure to the HMS hydrogen system controller 12 in real time, and the upper computer 13 is electrically connected with the HMS hydrogen system controller 12 and used for reading and monitoring the exhaust pressure measured by the pressure sensor 3.

The electrical input end of the replacement switch 11 is in hard-line connection with the storage battery 14, the electrical output end of the replacement switch 11 is in hard-line connection with the HMS hydrogen system controller 12, the replacement switch 11 is provided with an ON gear and an OFF gear, the storage battery 14 and the hydrogen system controller 12 are conducted when the replacement switch 11 is located at the ON gear, and the HMS hydrogen system controller 12 and the storage battery 14 are disconnected when the replacement switch 11 is located at the OFF gear.

Among the above components: the hydrogen bottle 1 is fixed on the vehicle and connected with the hydrogenation port 10 through a pipeline for storing gas (nitrogen/hydrogen). The hydrogen bottle electromagnetic valve 2 can be switched on and off according to power distribution of the HMS hydrogen system controller 12, the hydrogen bottle electromagnetic valve 2 is opened when the HMS hydrogen system controller 12 distributes power to the hydrogen bottle electromagnetic valve 2, and the hydrogen bottle electromagnetic valve 2 is closed when the power distribution is stopped, so that gas supply or cut-off supply is performed on a downstream pipeline. The pressure sensor 3 may collect the raw pressure signal in the bottle and convert it into a digital pressure signal that is sent to the HMS hydrogen system controller 12. The pressure relief valve 4 is used to regulate the high pressure gas in the cylinder to the pressure range of the downstream demand. The manual evacuation valve 5 is used to manually evacuate the low-pressure gas regulated by the pressure reducing valve 4. The check valve 6 serves to restrict the flow direction of intake air. The hydrogenation port 10 is mechanically connected with the gas filling device 9, and is used for conveying replacement gas (nitrogen/hydrogen) added from the gas filling device and conveying the replacement gas into the hydrogen bottle 1 through a pipeline. The HMS hydrogen system controller 12 is used for distributing power to the pressure sensors 3 and collecting digital pressure signals fed back by the pressure sensors, and the HMS hydrogen system controller 12 receives the hard-line signals of the replacement switch 11, controls the power distribution and the on-off of the hydrogen bottle electromagnetic valve 2 and performs signal interaction with the upper computer 13. The replacement switch 11 is hard-wired to the HMS hydrogen system controller 12, and is used to wake up and sleep the HMS hydrogen system controller 12 in the replacement mode, and the replacement switch 11 is disposed below the left trunk lid and is only used for the replacement mode operation, thereby avoiding the occurrence of misoperation. The upper computer 13 performs signal interaction with the HMS hydrogen system controller 12, reads a digital pressure signal output by the HMS hydrogen system controller 12, and displays the exhaust pressure. The battery 14 is a power source that supplies power to the HMS hydrogen system controller 12. In this embodiment, the upper computer 13 is an external computer, and the storage battery 14 is a 12V battery.

As shown in fig. 2, the method for controlling the gas replacement system of the fuel cell hybrid vehicle includes the steps of:

step one, confirming that a key of the whole vehicle is in an OFF gear;

step two, hydrogen cylinder exhaust

a. The replacement switch 11 is operated to be positioned at an ON gear, the HMS hydrogen system controller 12 and the storage battery 14 are conducted, the whole vehicle enters a replacement mode, and the HMS hydrogen system controller 12 completes awakening after receiving a conducting signal high-level signal sent by the storage battery 14;

controlling the opening of a hydrogen bottle electromagnetic valve 2 by a HMS hydrogen system controller 12, manually opening a manual emptying valve 5 to discharge gas in a hydrogen bottle 1 out of a vehicle, monitoring the exhaust pressure of the hydrogen bottle 1 in real time and adjusting the opening of the manual emptying valve 5, specifically, distributing power to a pressure sensor 3 by the HMS hydrogen system controller 12, enabling the pressure sensor 3 to start working and feeding back the exhaust pressure to the HMS hydrogen system controller 12 in real time, acquiring the exhaust pressure from the HMS hydrogen system controller 12 by an upper computer 13 and displaying the exhaust pressure in real time, observing the exhaust pressure displayed by the upper computer 13 in real time, and adjusting the opening of the manual emptying valve 5 according to the difference between the exhaust pressure and a preset exhaust pressure P2 (the difference is certainly larger than 0, and the opening of the manual emptying valve 5 is gradually reduced along with the gradual reduction of the difference); the operator closes the manual purge valve 5 to stop the hydrogen cylinder 1 from exhausting when the exhaust pressure reaches the preset pressure P2 (P2 is 0.5MPa in this embodiment),

c. The replacement switch 11 is operated to be positioned at an OFF gear to disconnect the HMS hydrogen system controller 12 and the storage battery 14, the HMS hydrogen system controller 12 controls the hydrogen bottle electromagnetic valve 2 to be closed and the pressure sensor 3 to stop working after receiving a disconnection signal sent by the storage battery 14, and the HMS hydrogen system controller 12 enters a dormant state;

step three, gas replacement

Repeating the second step to replace the nitrogen gas once after the nitrogen gas is filled into the hydrogen bottle 1 to the preset inflation pressure P1, wherein the step of filling the nitrogen gas into the hydrogen bottle 1 to the preset inflation pressure P1 specifically comprises the following steps: manually opening a nitrogen source 7 and a gas filling device 9, leading nitrogen in the nitrogen source 7 to a hydrogen bottle 1 through the gas filling device 9, observing a pressure gauge 15 until the pressure in the hydrogen bottle 1 reaches a preset inflation pressure P1 (P1 is 2.5MPa in the embodiment), manually closing the nitrogen source 7 and the gas filling device 9, and repeatedly performing nitrogen replacement for multiple times until the preset nitrogen replacement number N1 is reached (N1 is 5 in the embodiment);

the hydrogen replacement is performed by repeating the step two after the hydrogen is filled into the hydrogen bottle 1 to the preset inflation pressure P1, and the step of filling the hydrogen into the hydrogen bottle 1 to the preset inflation pressure P1 specifically comprises the following steps: manually starting a hydrogen source 8 and a gas filling device 9, leading hydrogen in the hydrogen source 8 to a hydrogen cylinder 1 through the gas filling device 9, observing a pressure gauge 15 until the pressure in the hydrogen cylinder 1 reaches a preset filling pressure P1 (in the embodiment, P1 is 2.5MPa), manually closing the hydrogen source 8 and the gas filling device 9, and repeatedly performing hydrogen replacement for multiple times until the preset hydrogen replacement number N2 is reached (in the embodiment, N2 is 5);

And the whole vehicle finishes the replacement process and exits from the replacement mode.

Generally, after a factory air tightness test, the internal pressure of the gas cylinder is several megapascals and is certainly greater than a preset exhaust pressure P2, and the nitrogen replacement times N1, the hydrogen replacement times N2, the preset exhaust pressure P2 and the preset inflation pressure P1 can be adjusted according to requirements.