Safety monitoring device for a hydrogen fuel engine

Abstract

The application discloses a safety monitoring device of a hydrogen fuel engine, which comprises a central processing unit, a hydrogen concentration sensor, a first data acquisition unit and a second data acquisition unit; the hydrogen concentration sensor respectively acquires a first hydrogen concentration in exhaust emission, a second hydrogen concentration generated by box purging and a third hydrogen concentration in a cabin; the first data acquisition unit acquires a first current generated by a low-voltage driving power supply; the second data acquisition unit acquires a second current generated by a high-voltage driving power supply and the temperature of the high-voltage driving power supply; when detecting that any hydrogen concentration is greater than a corresponding preset hydrogen concentration threshold value, the central processing unit controls the hydrogen fuel engine to shut down; when detecting that the first current is not less than a first current threshold value, the central processing unit cuts off the low-voltage driving power supply of the hydrogen fuel engine; when detecting that the second current is not less than a second current threshold value or the temperature of the high-voltage driving power supply is not less than a preset temperature threshold value, the central processing unit cuts off the high-voltage driving power supply of the hydrogen fuel engine.

Description

Technical Field

[0001] This invention relates to the field of hydrogen fuel cell engine technology, and in particular to a safety monitoring device for hydrogen fuel cell engines. Background Technology

[0002] With the continuous development of new energy sources, most existing new energy vehicles use hydrogen fuel cells as their power source. Spontaneous combustion of new energy vehicles due to hydrogen leaks and other reasons is a frequent occurrence. To address this, it is necessary to detect potential fire hazards in hydrogen fuel cells. However, existing safety detection devices primarily focus on detecting hydrogen leaks, which is insufficient for detecting fire hazards posed by hydrogen fuel cells. Summary of the Invention

[0003] This invention provides a safety monitoring device for hydrogen fuel cell engines, which can monitor various aspects of the safety of hydrogen fuel cell engines and improve the safety of their use.

[0004] One embodiment of the present invention provides a safety monitoring device for a hydrogen fuel cell engine, comprising: a central processing unit, hydrogen concentration sensors disposed in different areas of the hydrogen fuel cell engine, a first data acquisition unit, and a second data acquisition unit;

[0005] Several hydrogen concentration sensors are used to collect the first hydrogen concentration in the exhaust gas, the second hydrogen concentration generated by the box purging, and the third hydrogen concentration inside the chamber, respectively.

[0006] The first data acquisition unit is used to acquire the first current generated by the low-voltage drive power supply;

[0007] The second data acquisition unit is used to acquire the second current generated by the high-voltage drive power supply and the temperature of the high-voltage drive power supply;

[0008] The central processing unit is used to acquire the first hydrogen concentration, the second hydrogen concentration, the third hydrogen concentration, the first current, the second current, and the temperature of the high-voltage drive power supply in real time; when any hydrogen concentration is detected to be greater than the corresponding preset hydrogen concentration threshold, the unit controls the hydrogen fuel engine to shut down; when the first current is detected to be not less than the first current threshold, the unit cuts off the low-voltage drive power supply of the hydrogen fuel engine; when the second current is detected to be not less than the second current threshold or the temperature of the high-voltage drive power supply is not less than the preset temperature threshold, the unit cuts off the high-voltage drive power supply of the hydrogen fuel engine.

[0009] Furthermore, the step of controlling the hydrogen fuel cell engine to shut down when any hydrogen concentration is detected to be greater than a corresponding preset hydrogen concentration threshold includes:

[0010] When the first hydrogen concentration is detected to be greater than the first threshold, the hydrogen fuel engine is shut down.

[0011] When the second hydrogen concentration is detected to be greater than the second threshold, the hydrogen fuel engine is shut down.

[0012] When the third hydrogen concentration is detected to be greater than the third threshold, the hydrogen fuel engine is shut down.

[0013] Wherein, the first threshold is a hydrogen concentration threshold corresponding to the hydrogen concentration in the exhaust gas, the second threshold is a hydrogen concentration threshold corresponding to the hydrogen concentration during the purging of the chamber, and the third threshold is a hydrogen concentration threshold corresponding to the hydrogen concentration inside the chamber.

[0014] Furthermore, it also includes: a hydrogen proportional valve and a hydrogen exhaust valve;

[0015] The central processing unit is connected to the hydrogen proportional valve and the hydrogen tail exhaust valve, respectively.

[0016] The central processing unit is further configured to, when detecting that the first hydrogen concentration reaches a fourth threshold, control the opening degree of the hydrogen proportional valve to decrease and control the switching frequency of the hydrogen exhaust valve to decrease; when detecting that the first hydrogen concentration reaches a fifth threshold, control the opening degree of the hydrogen proportional valve to decrease and control the switching frequency of the hydrogen exhaust valve to decrease within a first preset time period, and obtain the first hydrogen concentration within the first preset time period; if the first hydrogen concentration within the first preset time period is greater than the fifth threshold, control the hydrogen fuel engine to shut down; wherein, the first threshold is greater than the fifth threshold, and the fifth threshold is greater than the fourth threshold.

[0017] The central processing unit, upon detecting that the first hydrogen concentration is greater than a first threshold, controls the hydrogen fuel cell engine to shut down, including:

[0018] When the first hydrogen concentration is detected to be greater than the first threshold, the hydrogen proportioning valve and the hydrogen exhaust valve are closed, and the hydrogen fuel engine is shut down.

[0019] Furthermore, the central processing unit is also used for:

[0020] When the second hydrogen concentration is detected to reach the sixth threshold, within a second preset time, the opening degree of the hydrogen proportional valve is reduced, the switching frequency of the hydrogen tail gas valve is reduced, and the second hydrogen concentration within the second preset time is obtained.

[0021] If the second hydrogen concentration is greater than the sixth threshold within the second preset time period, the hydrogen fuel engine is controlled to shut down; wherein the second threshold is greater than the sixth threshold.

[0022] Furthermore, the central processing unit is also used for:

[0023] When the third hydrogen concentration is detected to reach the seventh threshold, within a second preset time period, the opening degree of the hydrogen proportional valve is reduced, the switching frequency of the hydrogen tail gas valve is reduced, and the third hydrogen concentration within a third preset time period is obtained.

[0024] If the third hydrogen concentration is greater than the seventh threshold within a third preset time period, the hydrogen fuel engine is shut down; wherein the third threshold is greater than the seventh threshold.

[0025] Further, the step of cutting off the low-voltage drive power supply to the hydrogen fuel cell engine when the first current is detected to be not less than a first current threshold includes:

[0026] When the first current is detected to be not less than the first current threshold, a first duration for which the first current is not less than the first current threshold is obtained. If the first duration is not less than the first time threshold, the low-voltage drive power supply of the hydrogen fuel cell engine is cut off.

[0027] Further, when the second current is detected to be not less than a second current threshold or the temperature of the high-voltage drive power supply is not less than a preset temperature threshold, the high-voltage drive power supply of the hydrogen fuel cell engine is cut off, including:

[0028] When the second current is detected to be not less than the second current threshold, a second duration for which the second current is not less than the second current threshold is obtained. If the second duration is not less than the second time threshold, the high-voltage drive power supply of the hydrogen fuel cell engine is cut off.

[0029] When the temperature of the high-voltage drive power supply is detected to be not less than a preset temperature threshold, a third duration for which the temperature of the high-voltage drive power supply is not less than the preset temperature threshold is obtained. If the third duration is not less than a third time threshold, the high-voltage drive power supply of the hydrogen fuel cell engine is cut off.

[0030] Furthermore, it also includes: collision sensors;

[0031] The collision sensor is used to collect collision signals from the hydrogen fuel cell engine.

[0032] The central processing unit is also used to acquire collision signals in real time; when the collision signal is detected to be greater than a preset collision threshold, the drive power of the hydrogen fuel cell engine is cut off.

[0033] Furthermore, the number of collision sensors is multiple;

[0034] Each of the aforementioned collision sensors is positioned around the hydrogen fuel cell engine.

[0035] Furthermore, the step of cutting off the drive power to the hydrogen fuel cell engine when the detected collision signal exceeds a preset collision threshold includes:

[0036] If the collision signal is detected to be greater than the preset collision threshold, and if the hydrogen fuel engine is found to be fault-free, the high-voltage drive power supply and low-voltage drive power supply of the hydrogen fuel engine will be cut off sequentially after the hydrogen fuel engine has completed the shutdown purging.

[0037] If a fault is detected in the hydrogen fuel cell engine, the high-voltage drive power and low-voltage drive power of the hydrogen fuel cell engine will be cut off.

[0038] The following benefits can be obtained by implementing the present invention:

[0039] This invention provides a safety monitoring device for a hydrogen fuel cell engine, comprising: a central processing unit, hydrogen concentration sensors disposed in different areas of the hydrogen fuel cell engine, a first data acquisition unit, and a second data acquisition unit. The hydrogen concentration sensors in different areas of the hydrogen fuel cell engine acquire hydrogen concentrations at different locations in real time. The central processing unit monitors the hydrogen concentration in each area and shuts down the hydrogen fuel cell engine when any hydrogen concentration exceeds a set threshold, ensuring safe operation. Furthermore, the first and second data acquisition units acquire the current of the low-voltage drive power supply and the current and temperature of the high-voltage drive power supply in real time. When the central processing unit detects that the acquired current or temperature exceeds the corresponding set threshold, it cuts off the corresponding drive power supply to the hydrogen fuel cell engine, ensuring its safety. By monitoring the hydrogen content in different areas of the hydrogen fuel cell engine and monitoring its drive power supply, multi-faceted safety monitoring of the hydrogen fuel cell engine is achieved, improving the safety of its use. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of a safety monitoring device for a hydrogen fuel cell engine provided in an embodiment of the present invention.

[0041] Figure 2 This is a schematic diagram of a hydrogen path detection system for a hydrogen fuel cell engine provided in an embodiment of the present invention.

[0042] Figure 3 This is a schematic diagram of the low-pressure drive circuit current detection principle of a hydrogen fuel cell engine provided in an embodiment of the present invention.

[0043] Figure 4 This is a schematic diagram of the current and temperature detection principle of a high-pressure drive circuit for a hydrogen fuel cell engine, provided in an embodiment of the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] like Figure 1 The image shows a safety monitoring device for a hydrogen fuel cell engine provided in an embodiment of the present invention, comprising: a central processing unit, hydrogen concentration sensors disposed in different areas of the hydrogen fuel cell engine, a first data acquisition unit, and a second data acquisition unit;

[0046] Several hydrogen concentration sensors are used to collect the first hydrogen concentration in the exhaust gas, the second hydrogen concentration generated by the box purging, and the third hydrogen concentration inside the chamber, respectively.

[0047] The first data acquisition unit is used to acquire the first current generated by the low-voltage drive power supply;

[0048] The second data acquisition unit is used to acquire the second current generated by the high-voltage drive power supply and the temperature of the high-voltage drive power supply;

[0049] The central processing unit is used to acquire the first hydrogen concentration, the second hydrogen concentration, the third hydrogen concentration, the first current, the second current, and the temperature of the high-voltage drive power supply in real time; when any hydrogen concentration is detected to be greater than the corresponding preset hydrogen concentration threshold, the unit controls the hydrogen fuel engine to shut down; when the first current is detected to be not less than the first current threshold, the unit cuts off the low-voltage drive power supply of the hydrogen fuel engine; when the second current is detected to be not less than the second current threshold or the temperature of the high-voltage drive power supply is not less than the preset temperature threshold, the unit cuts off the high-voltage drive power supply of the hydrogen fuel engine.

[0050] Specifically, the safety monitoring device of the present invention is determined in conjunction with the safety-related engine control system (EMS); the safety monitoring of the hydrogen fuel engine is mainly carried out from the aspects of monitoring the hydrogen concentration of the hydrogen fuel engine and the driving power supply of the hydrogen fuel engine.

[0051] Hydrogen concentration monitoring in hydrogen fuel cell engines is primarily conducted from three aspects: monitoring the first hydrogen concentration in the engine exhaust, monitoring the second hydrogen concentration generated during engine casing purging, and monitoring the third hydrogen concentration within the engine compartment. By installing hydrogen concentration sensors at the engine exhaust, engine casing, and engine compartment, the first, second, and third hydrogen concentrations can be acquired in real time. These sensors are connected to the central processing unit (CPU) to enable the CPU to obtain these concentrations in real time.

[0052] In a preferred embodiment, controlling the hydrogen fuel engine to shut down when any hydrogen concentration is detected to be greater than a corresponding preset hydrogen concentration threshold includes: controlling the hydrogen fuel engine to shut down when the first hydrogen concentration is detected to be greater than a first threshold; controlling the hydrogen fuel engine to shut down when the second hydrogen concentration is detected to be greater than a second threshold; and controlling the hydrogen fuel engine to shut down when the third hydrogen concentration is detected to be greater than a third threshold; wherein the first threshold is a hydrogen concentration threshold corresponding to the exhaust emission hydrogen concentration, the second threshold is a hydrogen concentration threshold corresponding to the chamber purge hydrogen concentration, and the third threshold is a hydrogen concentration threshold corresponding to the chamber internal hydrogen concentration.

[0053] Specifically, the hydrogen concentration thresholds for different areas are different. When the central processing unit obtains the first hydrogen concentration, it compares it with the hydrogen concentration threshold corresponding to the exhaust hydrogen concentration (i.e., the aforementioned first threshold); when it obtains the second hydrogen concentration, it compares it with the hydrogen concentration threshold corresponding to the chamber purge hydrogen concentration (i.e., the aforementioned second threshold); when it obtains the third hydrogen concentration, it compares it with the hydrogen concentration threshold corresponding to the chamber's internal hydrogen concentration. If the central processing unit detects that any hydrogen concentration exceeds the corresponding set threshold during any of the above comparisons, it controls the hydrogen fuel cell engine to shut down to ensure the safe operation of the hydrogen fuel cell engine.

[0054] In a preferred embodiment, the system further includes: a hydrogen proportioning valve and a hydrogen exhaust valve; the central processing unit is connected to the hydrogen proportioning valve and the hydrogen exhaust valve respectively; the central processing unit is further configured to: when the first hydrogen concentration is detected to reach a fourth threshold, control the opening degree of the hydrogen proportioning valve to decrease and control the switching frequency of the hydrogen exhaust valve to decrease; when the first hydrogen concentration is detected to reach a fifth threshold, control the opening degree of the hydrogen proportioning valve to decrease and control the switching frequency of the hydrogen exhaust valve to decrease within a first preset time period, and obtain the first hydrogen concentration within the first preset time period; if the first hydrogen concentration within the first preset time period is greater than the fifth threshold, control the hydrogen fuel engine to shut down; wherein, the first threshold is greater than the fifth threshold, and the fifth threshold is greater than the fourth threshold; the central processing unit controlling the hydrogen fuel engine to shut down when it detects that the first hydrogen concentration is greater than the first threshold includes: controlling the hydrogen proportioning valve and the hydrogen exhaust valve to close and controlling the hydrogen fuel engine to shut down when it detects that the first hydrogen concentration is greater than the first threshold.

[0055] Specifically, such as Figure 2 As shown, the central processing unit is also connected to a hydrogen proportioning valve, a hydrogen switching valve, and a hydrogen exhaust valve. The hydrogen proportioning valve is used to control the amount of hydrogen supplied to the hydrogen fuel cell engine; the hydrogen switching valve is used to block or connect the hydrogen supply source; and the hydrogen exhaust valve is used to remove water and nitrogen generated after the hydrogen fuel cell engine reaction. Furthermore, based on the hydrogen reaction process, the gas discharged from the hydrogen exhaust valve may contain hydrogen.

[0056] The hydrogen concentration in the exhaust gas is monitored in real time. If the current hydrogen concentration in the exhaust gas reaches CO1% (i.e., the fourth threshold mentioned above), the central processing unit (CPU) reduces the hydrogen concentration through the hydrogen proportioning valve and the hydrogen on / off valve within a certain period of time. The CPU controls the opening degree of the hydrogen proportioning valve to reduce the hydrogen supply and controls the switching frequency of the hydrogen exhaust valve to reduce the opening frequency. To make the adjustment of the hydrogen proportioning valve and the hydrogen exhaust valve more accurate, a hydrogen pressure sensor is usually used to obtain the pressure of the hydrogen gas path where the currently detected hydrogen content is located. Within a certain period of time, the opening degree of the hydrogen proportioning valve and the switching frequency of the hydrogen exhaust valve are adjusted to reduce the output power of the hydrogen fuel cell engine.

[0057] If the hydrogen concentration in the exhaust gas is detected to reach CO2% (i.e., the fifth threshold mentioned above) and remains at CO2% for a certain period of time, the opening degree of the hydrogen proportional valve is reduced and the switching frequency of the hydrogen exhaust valve is decreased within a first preset time period, taking into account the pressure in the hydrogen gas path. During the adjustment period, the hydrogen concentration is acquired in real time. If the hydrogen concentration is detected to be lower than CO2%, there is no need to shut down the engine. If, after the above adjustments, the detected hydrogen concentration is still not lower than CO2%, the central processing unit sends a normal shutdown signal to the CAN transceiver to control the hydrogen fuel cell engine to shut down, and also sends a corresponding high hydrogen concentration warning signal to the CAN transceiver.

[0058] If the hydrogen concentration in the current exhaust gas reaches CO3% (i.e., the first threshold mentioned above), the central processing unit controls the hydrogen fuel cell engine to shut down urgently and closes the hydrogen proportioning valve, hydrogen exhaust valve, and hydrogen on / off valve. Specifically, CO1%... <C02%<C03%。

[0059] In a preferred embodiment, the central processing unit is further configured to: when the second hydrogen concentration is detected to reach a sixth threshold, within a second preset time period, control the opening degree of the hydrogen proportional valve to decrease, control the switching frequency of the hydrogen exhaust valve to decrease, and obtain the second hydrogen concentration within the second preset time period; if the second hydrogen concentration within the second preset time period is greater than the sixth threshold, control the hydrogen fuel engine to shut down; wherein, the second threshold is greater than the sixth threshold.

[0060] Specifically, when detecting the hydrogen concentration generated during the purging of the hydrogen fuel cell engine housing, if the detected hydrogen concentration reaches CO4% (i.e., the aforementioned sixth threshold) and remains at CO4% for a certain period, then within a second preset time, based on the pressure of the hydrogen gas path, the opening of the hydrogen proportional valve is reduced, and the switching frequency of the hydrogen exhaust valve is decreased. During this adjustment period, the hydrogen concentration is acquired in real time. If the detected hydrogen concentration decreases relative to CO4%, there is no need to shut down the engine. If, after the above adjustments, the detected hydrogen concentration is still not lower than CO4%, the central processing unit sends a normal shutdown signal to the CAN transceiver to control the hydrogen fuel cell engine shutdown and sends a corresponding high hydrogen concentration warning signal to the CAN transceiver.

[0061] If the hydrogen concentration detected during the current chamber purging reaches CO5% (i.e., the aforementioned second threshold), and remains at CO5% for a certain period, the opening of the hydrogen proportional valve and the switching frequency of the hydrogen exhaust valve are reduced again based on the current hydrogen gas pressure. If the detected hydrogen concentration is still greater than CO5% after adjusting the hydrogen proportional valve and the hydrogen exhaust valve, the central processing unit sends a normal shutdown signal to the CAN transceiver to control the hydrogen fuel cell engine to shut down, and also sends a corresponding high hydrogen concentration warning signal to the CAN transceiver. Among these, CO4%... <C05%。

[0062] In a preferred embodiment, the central processing unit is further configured to: when the third hydrogen concentration is detected to reach a seventh threshold, within a second preset time period, control the opening degree of the hydrogen proportional valve to decrease, control the switching frequency of the hydrogen exhaust valve to decrease, and obtain the third hydrogen concentration within a third preset time period; if the third hydrogen concentration within the third preset time period is greater than the seventh threshold, control the hydrogen fuel engine to shut down; wherein the third threshold is greater than the seventh threshold.

[0063] Specifically, when detecting hydrogen pipeline leaks in a hydrogen fuel cell engine, the main method is to monitor the hydrogen concentration inside the engine compartment. If the current hydrogen concentration inside the engine compartment reaches CO6% (i.e., the aforementioned seventh threshold) and remains at CO6% for a certain period of time, then within a third preset time period, based on the pressure of the hydrogen gas path, the opening degree of the hydrogen proportional valve is reduced, and the switching frequency of the hydrogen exhaust valve is decreased. During the adjustment period, the hydrogen concentration is acquired in real time. If the hydrogen concentration is detected to be lower than CO6%, there is no need to shut down the engine. If, after the above adjustments, the detected hydrogen concentration is still not lower than CO6%, the central processing unit sends a normal shutdown signal to the CAN transceiver to control the hydrogen fuel cell engine to shut down, and also sends a corresponding warning signal for excessively high hydrogen concentration to the CAN transceiver.

[0064] If the hydrogen concentration in the engine compartment reaches C07% (i.e., the third threshold mentioned above) and remains at C07% for a certain period, the opening of the hydrogen proportioning valve and the switching frequency of the hydrogen exhaust valve are reduced again based on the current hydrogen gas pressure. If the detected hydrogen concentration is still greater than C07% after adjusting the hydrogen proportioning valve and the hydrogen exhaust valve, the central processing unit sends a normal shutdown signal to the CAN transceiver to control the hydrogen fuel cell engine to shut down, and also sends a corresponding high hydrogen concentration warning signal to the CAN transceiver. C06% <C07%。

[0065] It should be noted that the above-mentioned detection of hydrogen concentration in various areas of the hydrogen fuel cell engine mainly refers to monitoring the hydrogen concentration in the air when it is between 4.0% and 75.6% under actual operating conditions.

[0066] In a preferred embodiment, the step of cutting off the low-voltage drive power supply of the hydrogen fuel cell engine when the first current is detected to be not less than the first current threshold includes: when the first current is detected to be not less than the first current threshold, obtaining a first duration during which the first current is not less than the first current threshold; and if the first duration is not less than the first time threshold, cutting off the low-voltage drive power supply of the hydrogen fuel cell engine.

[0067] Specifically, the first data acquisition unit and the second data acquisition unit are in Figure 2 All data are represented by an ADC (Analog-to-Digital Converter) data acquisition unit. In addition to monitoring the hydrogen concentration in the hydrogen fuel cell engine, this invention also monitors the low-voltage drive power supply of the hydrogen fuel cell engine. The monitoring principle of the low-voltage drive power supply of the hydrogen fuel cell engine in this invention is based on the principle proposed in this invention. Figure 3 The circuit diagram shown includes: a microcontroller unit, an ADC data acquisition unit (referring to the first data acquisition unit mentioned above), an operational amplifier unit, a CAN transceiver, field-effect transistors, resistors, and capacitors. Power is supplied to the central processing unit, distributed to each drive terminal according to power requirements. The operational amplifier sampling differential amplifier circuit detects the output current of the circuit, and transmits the amplified sampled signal to the ADC data acquisition chip. The microcontroller unit calculates the sampled current A01, which is the first current acquired by the first data acquisition unit. The microcontroller unit then sends this signal to the central processing unit.

[0068] If the acquired A01 is less than A11 (i.e., the aforementioned first current threshold), the central processing unit controls the hydrogen fuel cell engine to operate normally; if the acquired A01 is greater than or equal to A11, the central processing unit acquires the duration T01 of A01 detection (i.e., the aforementioned first duration); if T01 is less than T11 (i.e., the aforementioned first time threshold), the central processing unit controls the hydrogen fuel cell engine to operate normally; if T01 is greater than or equal to T11, the central processing unit sends a normal shutdown command, waits for the hydrogen fuel cell engine to shut down and purge, and then controls the corresponding low-voltage drive circuit to disconnect through the microcontroller unit, cutting off the corresponding low-voltage drive power supply; and after cutting off the corresponding low-voltage drive power supply, it sends an alarm signal to the external display instrument of the hydrogen fuel cell engine through the CAN transceiver, displaying low-voltage overcurrent fault information.

[0069] It should be noted that the relationship between the first current threshold, the first time threshold, and the sampling data of the data acquisition unit is determined by identifying the fault of the load under test based on the on / off state of the switch module and the target sampling data, under the condition that all drive modules are in the off state. If the load under test is short-circuited, the sampling data acquired by the detection module from the sampling module directly connected to the sampling module will change when the switch module is in the off state. When the switch module is in the closed state, if the load under test is short-circuited to the reference voltage terminal, the sampling data acquired by the detection module will change.

[0070] In a preferred embodiment, cutting off the high-voltage drive power supply of the hydrogen fuel cell engine when the second current is detected to be not less than a second current threshold or the temperature of the high-voltage drive power supply is not less than a preset temperature threshold includes: when the second current is detected to be not less than the second current threshold, obtaining a second duration for which the second current is not less than the second current threshold; if the second duration is not less than a second time threshold, cutting off the high-voltage drive power supply of the hydrogen fuel cell engine; when the temperature of the high-voltage drive power supply is detected to be not less than the preset temperature threshold, obtaining a third duration for which the temperature of the high-voltage drive power supply is not less than the preset temperature threshold; if the third duration is not less than a third time threshold, cutting off the high-voltage drive power supply of the hydrogen fuel cell engine.

[0071] Specifically, this invention also monitors the high-voltage drive power supply of a hydrogen fuel cell engine. The monitoring principle of this invention for the high-voltage drive power supply of a hydrogen fuel cell engine is based on the principles proposed in this invention. Figure 4 The circuit diagram shown includes: a Hall sensor (marked with the symbol H in the diagram), an operational amplifier unit, a CAN transceiver, a field-effect transistor, a resistor, a thermistor, an ADC data acquisition unit, and a microcontroller unit. The Hall sensor can be integrated into a DC-DC converter, which includes the hydrogen fuel cell engine system BOP (air compressor, hydrogen circulation pump, PTC heater, water pump) and the hydrogen fuel cell electric propulsion input to the DC-DC converter, as well as the high-voltage loop current detection at the power output terminal after the hydrogen fuel cell generates electricity and supplies it to the DC-DC converter. The current A02 (i.e., the aforementioned second current) detected by the Hall sensor in the DC-DC converter is transmitted to the central processing unit via the CAN transceiver. The high-voltage connection lines from the DC-DC converter to each BOP auxiliary component have their high-voltage wiring harness temperature W01 (i.e., the temperature of the aforementioned high-voltage drive power supply) measured by the thermistor R15, and the detected current A02 and temperature W01 are transmitted to the microcontroller unit, which then transmits the data to the central processing unit.

[0072] If A02 is less than A21 (i.e., the second current threshold mentioned above), the central processing unit controls the hydrogen fuel cell engine to operate normally. If the acquired A02 is greater than or equal to A21, the central processing unit acquires the duration T02 of A02 detection (i.e., the second duration mentioned above). If T02 is less than T21 (i.e., the second time threshold mentioned above), the central processing unit controls the hydrogen fuel cell engine to operate normally. If T02 is greater than or equal to T21, the central processing unit sends a normal shutdown command. After the hydrogen fuel cell engine shutdown purging is completed, the central processing unit controls the corresponding high-voltage drive circuit to disconnect through the microcontroller unit, cutting off the corresponding high-voltage drive power supply. After cutting off the corresponding high-voltage drive power supply, an alarm signal is sent to the external display instrument of the hydrogen fuel cell engine through the CAN transceiver to display high-voltage overcurrent fault information.

[0073] If W01 is less than temperature W02 (i.e., the aforementioned preset temperature threshold), the central processing unit controls the hydrogen fuel cell engine to operate normally; if W01 is greater than or equal to W02, the central processing unit obtains the duration T03 of detecting W01; if T03 is less than T31 (i.e., the aforementioned third time threshold), the central processing unit controls the hydrogen fuel cell engine to operate normally; if T03 is greater than or equal to T31, the central processing unit sends a normal shutdown command, waits for the hydrogen fuel cell engine to shut down and purge, and then controls the corresponding high-voltage drive circuit to disconnect through the microcontroller unit, cutting off the corresponding high-voltage drive power supply; and after cutting off the corresponding high-voltage drive power supply, it sends an alarm signal to the external display instrument of the hydrogen fuel cell engine through the CAN transceiver, displaying the wiring harness high temperature fault information.

[0074] It should be noted that the determination of the second current threshold and the second time threshold is based on the ambient temperature T31 of the hydrogen fuel cell engine's environmental conductors in different hydrogen fuel cell engine systems. Different types and materials of conductors are selected to ensure that, under the maximum permissible current, the following high-temperature conditions do not occur at the connection between the terminal and the conductor. Experiments have shown that when the current in the selected conductor exceeds the safe current n1 times, the conductor core temperature can reach T41, the local insulation layer bubbles and separates from the conductor core, and local smoke appears; when the conductor carries a current n2 times the safe current, the conductor core temperature can reach T51, the conductor core turns red, and the insulation layer ignites. On the other hand, because the insulation layer is exposed to high temperatures for a long time, its organic components gradually carbonize. The carbonized parts may form semiconductors, reducing the conductor's insulation level. This may cause short circuits to ground or between lines, or leakage, further increasing the load and generating even higher temperatures. This creates a vicious cycle, which in turn leads to a fire. According to Joule's law Q=I 2Rt, the relevant temperature rise change value is calculated based on the maximum allowable current, time, and wire diameter. Then, based on the detected ambient temperature of the hydrogen fuel engine, the maximum allowable current value of the wire when it is subjected to the maximum temperature is calculated to determine the second current threshold A21 and the second time threshold T21.

[0075] In a preferred embodiment, the system further includes: a collision sensor; the collision sensor is used to collect collision signals from the hydrogen fuel cell engine; the central processing unit is also used to acquire the collision signals in real time; and when the collision signal is detected to be greater than a preset collision threshold, the power supply to the hydrogen fuel cell engine is cut off.

[0076] Specifically, the present invention also performs collision monitoring on the hydrogen fuel engine by acquiring collision signals of the hydrogen fuel engine through collision sensors installed on the hydrogen fuel engine; the central processing unit determines whether to control the hydrogen fuel engine to shut down based on the acquired collision signals.

[0077] In a preferred embodiment, there are multiple collision sensors; each collision sensor is disposed around the hydrogen fuel cell engine.

[0078] Specifically, to comprehensively monitor collisions to the hydrogen fuel cell engine, a collision sensor can be installed in each of the four directions (front, rear, left, and right) to monitor collision signals from all directions. It should be noted that the number of collision sensors and their placement on the hydrogen fuel cell engine can be adjusted according to actual needs. This embodiment only illustrates one feasible scenario; other deployment scenarios will not be elaborated upon here.

[0079] In a preferred embodiment, the step of cutting off the drive power supply of the hydrogen fuel cell engine when the collision signal is detected to be greater than a preset collision threshold includes: if the hydrogen fuel cell engine is found to be fault-free, then after the hydrogen fuel cell engine has completed shutdown purging, sequentially cutting off the high-voltage drive power supply and the low-voltage drive power supply of the hydrogen fuel cell engine; if the hydrogen fuel cell engine is found to be faulty, then cutting off the high-voltage drive power supply and the low-voltage drive power supply of the hydrogen fuel cell engine.

[0080] Specifically, the hydrogen fuel cell engine has a built-in detection unit to check for malfunctions. When a collision signal transmitted by any collision sensor exceeds a set collision threshold, the system acquires the collision state of the hydrogen fuel cell engine under the current collision. If no malfunction is detected, after the engine completes shutdown and purging, the high-voltage drive power is first cut off, followed by the low-voltage drive power. If a malfunction is detected, all hydrogen valves (including the hydrogen proportioning valve, hydrogen on / off valve, and hydrogen exhaust valve) are directly shut off, along with both the high-voltage and low-voltage drive power supplies.

[0081] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Furthermore, in the accompanying drawings of the device embodiments provided by this invention, the connection relationships between modules indicate that they have communication connections, which can be specifically implemented as one or more communication buses or signal lines. Those skilled in the art can understand and implement this without any creative effort.

[0082] Those skilled in the art will clearly understand that, for convenience and brevity, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0083] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A safety monitoring device for a hydrogen fuel cell engine, characterized in that, include: The system includes a central processing unit, hydrogen concentration sensors located in different areas of the hydrogen fuel cell engine, a first data acquisition unit, and a second data acquisition unit. Several hydrogen concentration sensors are used to collect the first hydrogen concentration in the exhaust gas, the second hydrogen concentration generated by the box purging, and the third hydrogen concentration inside the chamber, respectively. The first data acquisition unit is used to acquire the first current generated by the low-voltage drive power supply; The second data acquisition unit is used to acquire the second current generated by the high-voltage drive power supply and the temperature of the high-voltage drive power supply; The central processing unit is used to acquire the first hydrogen concentration, the second hydrogen concentration, the third hydrogen concentration, the first current, the second current, and the temperature of the high-voltage drive power supply in real time; when any hydrogen concentration is detected to be greater than the corresponding preset hydrogen concentration threshold, the unit controls the hydrogen fuel engine to shut down; when the first current is detected to be not less than the first current threshold, the unit acquires the first duration for which the first current is not less than the first current threshold, and if the first duration is not less than the first time threshold, the unit cuts off the low-voltage drive power supply of the hydrogen fuel engine; when the second current is detected to be not less than the second current threshold, the unit acquires the second duration for which the second current is not less than the second current threshold, and if the second duration is not less than the second time threshold, the unit cuts off the high-voltage drive power supply of the hydrogen fuel engine. When the temperature of the high-voltage drive power supply is detected to be not less than a preset temperature threshold, a third duration for which the temperature of the high-voltage drive power supply is not less than the preset temperature threshold is obtained. If the third duration is not less than a third time threshold, the high-voltage drive power supply of the hydrogen fuel cell engine is cut off.

2. The safety monitoring device for a hydrogen fuel cell engine as described in claim 1, characterized in that, The step of controlling the hydrogen fuel engine to shut down when any hydrogen concentration is detected to be greater than a corresponding preset hydrogen concentration threshold includes: When the first hydrogen concentration is detected to be greater than the first threshold, the hydrogen fuel engine is shut down. When the second hydrogen concentration is detected to be greater than the second threshold, the hydrogen fuel engine is shut down. When the third hydrogen concentration is detected to be greater than the third threshold, the hydrogen fuel engine is shut down. Wherein, the first threshold is a hydrogen concentration threshold corresponding to the hydrogen concentration in the exhaust gas, the second threshold is a hydrogen concentration threshold corresponding to the hydrogen concentration in the chamber purge, and the third threshold is a hydrogen concentration threshold corresponding to the hydrogen concentration inside the chamber.

3. The safety monitoring device for a hydrogen fuel cell engine as described in claim 2, characterized in that, Also includes: Hydrogen proportional valve and hydrogen tail exhaust valve; The central processing unit is connected to the hydrogen proportional valve and the hydrogen tail exhaust valve, respectively. The central processing unit is further configured to, when detecting that the first hydrogen concentration reaches a fourth threshold, control the opening degree of the hydrogen proportional valve to decrease and control the switching frequency of the hydrogen exhaust valve to decrease; when detecting that the first hydrogen concentration reaches a fifth threshold, control the opening degree of the hydrogen proportional valve to decrease and control the switching frequency of the hydrogen exhaust valve to decrease within a first preset time period, and obtain the first hydrogen concentration within the first preset time period; if the first hydrogen concentration within the first preset time period is greater than the fifth threshold, control the hydrogen fuel engine to shut down; wherein, the first threshold is greater than the fifth threshold, and the fifth threshold is greater than the fourth threshold. The central processing unit, upon detecting that the first hydrogen concentration is greater than a first threshold, controls the hydrogen fuel cell engine to shut down, including: When the first hydrogen concentration is detected to be greater than the first threshold, the hydrogen proportioning valve and the hydrogen exhaust valve are closed, and the hydrogen fuel engine is shut down.

4. The safety monitoring device for a hydrogen fuel cell engine as described in claim 3, characterized in that, The central processing unit is also used for: When the second hydrogen concentration is detected to reach the sixth threshold, within a second preset time, the opening degree of the hydrogen proportional valve is reduced, the switching frequency of the hydrogen tail gas valve is reduced, and the second hydrogen concentration within the second preset time is obtained. If the second hydrogen concentration is greater than the sixth threshold within the second preset time period, the hydrogen fuel engine is controlled to shut down; wherein the second threshold is greater than the sixth threshold.

5. A safety monitoring device for a hydrogen fuel cell engine as described in claim 3, characterized in that, The central processing unit is also used for: When the third hydrogen concentration is detected to reach the seventh threshold, within a second preset time period, the opening degree of the hydrogen proportional valve is reduced, the switching frequency of the hydrogen tail gas valve is reduced, and the third hydrogen concentration within a third preset time period is obtained. If the third hydrogen concentration is greater than the seventh threshold within a third preset time period, the hydrogen fuel engine is shut down; wherein the third threshold is greater than the seventh threshold.

6. The safety monitoring device for a hydrogen fuel cell engine as described in claim 1, characterized in that, Also includes: Collision sensor; The collision sensor is used to collect collision signals from the hydrogen fuel cell engine. The central processing unit is also used to acquire collision signals in real time; when the collision signal is detected to be greater than a preset collision threshold, the drive power of the hydrogen fuel cell engine is cut off.

7. A safety monitoring device for a hydrogen fuel cell engine as described in claim 6, characterized in that, The number of collision sensors is multiple; Each of the aforementioned collision sensors is positioned around the hydrogen fuel cell engine.

8. A safety monitoring device for a hydrogen fuel cell engine as described in claim 6, characterized in that, The step of cutting off the drive power to the hydrogen fuel cell engine when the detected collision signal exceeds a preset collision threshold includes: If the collision signal is detected to be greater than the preset collision threshold, and if the hydrogen fuel engine is found to be fault-free, the high-voltage drive power supply and low-voltage drive power supply of the hydrogen fuel engine will be cut off sequentially after the hydrogen fuel engine has completed the shutdown purging. If a fault is detected in the hydrogen fuel cell engine, the high-voltage drive power and low-voltage drive power of the hydrogen fuel cell engine will be cut off.

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