Engine detection system

Abstract

The invention discloses an engine detection system which comprises a fuel stop valve, a nitrogen stop valve, a nitrogen ventilation valve, a deflation electromagnetic valve, a discharge electromagnetic valve and a controller. The fuel stop valve is used for on-off control of a fuel supply pipeline, the nitrogen stop valve is used for on-off control of a nitrogen pipeline, the nitrogen breather valve is used for on-off control of a nitrogen discharge pipeline, the deflation electromagnetic valve is used for on-off control of a gas fuel discharge pipeline, and the release electromagnetic valve is used for on-off control of a liquid fuel discharge pipeline. The controller is configured to obtain a detection instruction, and the detection instruction is used for controlling the fuel stop valve, the nitrogen stop valve, the nitrogen ventilation valve, the deflation electromagnetic valve and the discharge electromagnetic valve to be in designated on-off states; the specified on-off state corresponds to one of a pressure maintaining mode, a pressure relief mode, a dual-fuel entering mode, a dual-fuel exiting mode, a purging mode and a reset mode.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of automatic control technology, and in particular to an engine detection system. Background Art

[0002] Against the backdrop of the booming new energy industry, alternative fuels such as green hydrogen, methanol, and ammonia have been increasingly widely used in the field of engine research and development due to their environmental protection and abundant resources.

[0003] When a dual-fuel engine operates in dual-fuel mode, the valve unit is crucial for controlling the supply of alternative fuels. However, alternative fuels such as methanol and ammonia are toxic, posing a safety hazard during engine development testing on the test bench. Improper control of the valve unit during testing can lead to fuel leaks, threatening the lives and health of test personnel.

[0004] Traditional valve block control methods have numerous shortcomings. They lack automated process control, resulting in low efficiency. Furthermore, test personnel frequently operate in close proximity, making it difficult to ensure precise timing control of the valve block. Furthermore, manual operation is unable to promptly address potential solenoid valve failures, such as sticking, severely impacting the smooth progress of engine R&D testing. Summary of the Invention

[0005] The present invention provides an engine detection system to achieve the purpose of solving at least one defect existing in the prior art.

[0006] An embodiment of the present invention provides an engine detection system, comprising: a fuel shut-off valve, a nitrogen shut-off valve, a nitrogen breather valve, a vent solenoid valve, a discharge solenoid valve, and a controller;

[0007] The fuel shut-off valve is used for on-off control of the fuel supply pipeline, the nitrogen shut-off valve is used for on-off control of the nitrogen pipeline, the nitrogen breather valve is used for on-off control of the nitrogen discharge pipeline, the purge solenoid valve is used for on-off control of the gas fuel discharge pipeline, and the discharge solenoid valve is used for on-off control of the liquid fuel discharge pipeline;

[0008] The controller is configured to obtain a detection instruction, wherein the detection instruction is used to control the fuel shut-off valve, the nitrogen shut-off valve, the nitrogen breather valve, the purge solenoid valve, and the discharge solenoid valve to be placed in a specified on-off state respectively;

[0009] The designated on-off state corresponds to one of a pressure maintaining mode, a pressure relief mode, entering a dual fuel mode, exiting a dual fuel mode, a purge mode, and a reset mode.

[0010] Optionally, a spare fuel shut-off valve is further included, and the spare shut-off valve is used for on-off control of the fuel supply pipeline;

[0011] The controller is further configured to obtain a detection current of the fuel cut-off valve, and control the backup cut-off valve to open when the detection current is abnormal.

[0012] Optionally, the nitrogen stop valve includes a first nitrogen stop valve and a second nitrogen stop valve;

[0013] The first nitrogen shut-off valve and the second nitrogen shut-off valve are arranged in series, and the nitrogen breathable valve is arranged on the pipeline between the first nitrogen shut-off valve and the second nitrogen shut-off valve;

[0014] The on-off states of the first nitrogen shut-off valve and the second nitrogen shut-off valve are the same.

[0015] Optionally, the controller is further configured to obtain detection currents of the nitrogen shut-off valve, nitrogen breather valve, vent solenoid valve, and discharge solenoid valve, and generate an alarm prompt message when any of the detection currents is abnormal.

[0016] Optionally, the initial states of the fuel shut-off valve, the nitrogen shut-off valve, the purge solenoid valve, and the discharge solenoid valve are set to be closed, and the initial state of the nitrogen breathable valve is set to be open.

[0017] Optionally, when entering the dual fuel mode, the air release solenoid valve, fuel shut-off valve, and nitrogen breather valve are controlled to open, and the discharge solenoid valve and nitrogen shut-off valve are controlled to close.

[0018] After entering the dual fuel mode, it is determined whether the difference between the fuel filter pressure and the fuel supply pressure is less than a preset threshold. If so, the air release solenoid valve is controlled to close.

[0019] Optionally, when exiting the dual fuel mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to be open, and the nitrogen breather valve, the fuel shut-off valve, and the air release solenoid valve are controlled to be closed;

[0020] 20 seconds after exiting the dual fuel mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to close, and the vent solenoid valve and the nitrogen breather valve are controlled to open;

[0021] 25 seconds after exiting the dual fuel mode, the purge solenoid valve is controlled to close.

[0022] Optionally, when entering the pressure maintaining mode, the nitrogen shut-off valve is controlled to open and the other valves are closed.

[0023] Optionally, when entering the pressure relief mode, the air release solenoid valve and the nitrogen breather valve are controlled to open, and the other valves are closed;

[0024] After entering the pressure relief mode for 20 seconds, the air release solenoid valve is controlled to close.

[0025] Optionally, when entering the purge mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to open, and the air release solenoid valve, the nitrogen breathable valve, and the fuel shut-off valve are controlled to close.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention proposes an engine detection system that can realize automatic valve control, thereby reducing the need for manual operation. The system can automatically complete valve movements, reducing the labor intensity of frequent manual valve operation, avoiding the risks brought by manual operation errors, and ensuring the safety of operators. The system can be placed in different modes by controlling the on and off of the solenoid valve, and the controller can control the on and off of the valve according to the detection instructions to achieve smooth switching of different modes. In different modes, each valve can accurately control the flow and discharge of gas fuel, maintain the stability of fuel supply and discharge, and make the engine operating state transition smoothly, avoiding engine operation abnormalities caused by mode switching, and ensuring the stable and reliable operation of the entire detection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 1 is a schematic structural diagram of an engine detection system in an embodiment;

[0028] Figure 2 is a schematic structural diagram of another engine detection system in an embodiment;

[0029] Figure 3 is a schematic diagram of the detection logic in the embodiment;

[0030] Figure 4 Schematic diagram of the valve assembly circuit in the embodiment. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0032] Figure 1 This is a schematic diagram of the engine detection system structure in the embodiment, refer to Figure 1 The engine detection system includes a fuel cut-off valve 11, a nitrogen cut-off valve 12, a nitrogen breather valve 13, a purge solenoid valve 14, a discharge solenoid valve 15 and a controller.

[0033] In this solution, the fuel shut-off valve 11 is used for on-off control of the fuel supply pipeline, the nitrogen shut-off valve 12 is used for on-off control of the nitrogen pipeline, the nitrogen breather valve 13 is used for on-off control of the nitrogen discharge pipeline, the vent solenoid valve 14 is used for on-off control of the gas fuel discharge pipeline, and the discharge solenoid valve 15 is used for on-off control of the liquid fuel discharge pipeline.

[0034] In this solution, the fuel shut-off valve 11 and the nitrogen shut-off valve 12 are arranged at the fuel inlet end of the engine 1, the bleed solenoid valve 14 and the discharge solenoid valve 15 are arranged at the fuel outlet end of the engine 1, and the nitrogen breather valve 13 is arranged on the pipeline between the nitrogen shut-off valve 12 and the engine 1.

[0035] In this solution, fuel shutoff valve 11 is primarily responsible for on-off control of the fuel supply line. When the engine is running, the fuel shutoff valve opens, allowing fuel to flow smoothly through the supply line, providing the energy required for engine combustion. When the engine no longer needs fuel or a malfunction requires shutting off the fuel supply, the fuel shutoff valve closes, preventing further fuel from flowing into the engine and ensuring the safety of equipment and personnel.

[0036] In this solution, nitrogen shutoff valve 12 is used to control the nitrogen pipeline. During certain engine operating phases, nitrogen is required for specific operations, such as pressure maintenance testing and nitrogen purging. When the nitrogen shutoff valve is open, nitrogen can flow through the nitrogen pipeline, achieving the corresponding function; when closed, it shuts off the nitrogen pipeline, controlling nitrogen delivery.

[0037] In this solution, nitrogen vent valve 13 is responsible for on-off control of the nitrogen exhaust line. During engine operation, when nitrogen is not needed or when nitrogen in the line needs to be exhausted, the nitrogen vent valve opens to allow nitrogen to be discharged to the atmosphere. Otherwise, when nitrogen pressure in the line needs to be maintained, the nitrogen vent valve closes.

[0038] In this solution, the purge solenoid valve 14 is used to control the on / off status of the gas fuel discharge line. During engine operation, some unburned gas fuel is produced. When the purge solenoid valve is open, this unburned gas fuel can be discharged through the discharge line; when closed, it prevents gas fuel from being discharged. During the phases of entering and exiting dual-fuel mode, the purge solenoid valve opens to discharge unburned gas fuel from the line, ensuring line safety and normal engine operation.

[0039] In this solution, the drain solenoid valve 15 is used to control the on / off status of the liquid fuel discharge line. Similar to the bleed solenoid valve, when unburned liquid fuel in the engine needs to be discharged, the drain solenoid valve opens, allowing the liquid fuel to be discharged through the discharge line; when closed, it blocks the liquid fuel discharge line. After exiting dual-fuel mode and performing a nitrogen purge, the drain solenoid valve opens to discharge any remaining liquid fuel, preventing damage to the equipment.

[0040] In this solution, the controller is configured to obtain a detection instruction, which is used to control the fuel shut-off valve, nitrogen shut-off valve, nitrogen breather valve, vent solenoid valve, and discharge solenoid valve to be placed in a specified on-off state respectively.

[0041] For example, in this solution, there is no limitation on the format of the detection instruction, which can be in digital format or text format, etc.

[0042] The detection instruction can use different bits of a byte to indicate different operating modes, and use several other bytes to indicate the valve status. For example, the first byte 0x01 indicates the pressure holding mode, and the following bytes indicate the valve status in binary or hexadecimal.

[0043] In this solution, the designated on / off state corresponds to one of a pressure maintaining mode, a pressure relief mode, entering a dual fuel mode, exiting a dual fuel mode, a purge mode, and a reset mode.

[0044] In this solution, the pressure-maintaining mode is mainly used to detect the sealing of engine-related pipelines and systems, ensuring that the system will not leak under a certain pressure, and ensuring the safety and stability of the subsequent operation of the engine.

[0045] For example, in this solution, when entering pressure-maintaining mode, the nitrogen shutoff valve can be opened to inject nitrogen into the system to achieve and maintain a specific pressure. The fuel shutoff valve is closed to prevent fuel from entering the system and affecting pressure test results. The nitrogen vent valve, bleed solenoid valve, and drain solenoid valve are closed to prevent gas leakage and maintain stable system pressure.

[0046] For example, the controller monitors the pressure of the corresponding pipeline in the system in real time. If the pressure drops, it may indicate that there is a leak in the system and further investigation is required.

[0047] For example, in this solution, the pressure relief mode is mainly used when the system pressure is too high or it is necessary to stop detection, maintenance and other operations, and the pressure in the system needs to be released to a safe range to avoid harm to equipment and personnel.

[0048] For example, in this solution, when pressure relief mode is entered, the nitrogen vent valve can be controlled to open, releasing nitrogen from the system to the atmosphere and reducing system pressure. The purge and drain solenoid valves can be opened to remove any remaining gaseous and liquid fuel from the system. The nitrogen shutoff valve can be closed to stop nitrogen injection into the system.

[0049] The controller continuously monitors the system pressure until the pressure drops to a safe level.

[0050] For example, in this solution, the engine can operate simultaneously using two different fuels (such as gas fuel and liquid fuel) in dual-fuel mode to improve the adaptability and performance of the engine. For example, under different working conditions, a suitable fuel combination can be selected according to the fuel supply and economy.

[0051] For example, in this solution, when dual-fuel mode is entered, the fuel shutoff valve can be controlled to open, allowing gaseous and liquid fuels to enter the engine's combustion system. The purge and bleed solenoid valves are closed to prevent fuel leakage and ensure full fuel utilization. The nitrogen shutoff valve is closed to maintain stable pressure in the system, ensuring a normal fuel supply.

[0052] Illustratively, in this solution, when exiting the dual fuel mode, the fuel shut-off valve may be controlled to close.

[0053] For example, in this solution, the purge mode is used to purge the pipes and components in the system with nitrogen after the engine stops running, to remove residual fuel and impurities, prevent fuel residue from causing safety hazards, and also help protect the equipment and extend its service life.

[0054] For example, in this embodiment, when entering the purge mode, the nitrogen shutoff valve can be controlled to open to inject nitrogen into the system. The nitrogen breather valve, the bleed solenoid valve, and the fuel shutoff valve can be closed to allow nitrogen to flow through the system and discharge the remaining fuel and impurities through the exhaust line.

[0055] Exemplarily, in this solution, the reset mode is used to restore the various valves and components of the engine detection system to their initial states, preparing for the next detection or operation, and ensuring the consistency and reliability of the system.

[0056] For example, in this solution, upon entering reset mode, the fuel shutoff valve, nitrogen shutoff valve, purge solenoid valve, and bleed solenoid valve are closed, and the nitrogen breather valve is opened. The controller's relevant data and status information are cleared, returning it to its initial settings. System parameters and indicators are checked to ensure the system is in a normal standby state.

[0057] For example, in this solution, the fuel shut-off valve, nitrogen shut-off valve, purge solenoid valve, and discharge solenoid valve are normally closed control valves, and the nitrogen breather valve is a normally open control valve.

[0058] For example, in this embodiment, the control terminal of a normally closed control valve can be connected to an output pin of a controller via a drive circuit. The drive circuit can be composed of a relay, with one end of the relay coil connected to a power source and the other end connected to an output pin of the controller. The normally open contact of the relay is connected to the power supply terminal of the valve.

[0059] Under normal conditions, the controller's output pin outputs a low level, no current flows through the relay coil, the normally open contact opens, and the valve is closed. When the controller receives a detection instruction to open the valve, the output pin outputs a high level, current flows through the relay coil, the normally open contact closes, and the valve opens.

[0060] Exemplarily, in this solution, the control end of the normally open control valve is connected to the output pin of the controller through a drive circuit.

[0061] Under normal conditions, the controller's output pin outputs a low level, and the valve is open. When the controller receives a detection instruction to close the valve, the output pin outputs a high level, and the valve is closed through the drive circuit.

[0062] This embodiment proposes an engine detection system that can realize automatic valve control, thereby reducing the need for manual operation. The system can automatically complete the valve movement, reducing the labor intensity of frequent manual valve operation, avoiding the risks brought by manual operation errors, and ensuring the safety of operators. The system can be placed in different modes by controlling the on and off of the solenoid valve, and the controller can control the valve on and off according to the detection instructions to achieve smooth switching between different modes. In different modes, each valve can accurately control the flow and discharge of gas and fuel, maintain the stability of fuel supply and discharge, and make the engine operating state transition smoothly, avoiding engine operation abnormalities caused by mode switching, and ensuring the stable and reliable operation of the entire detection system.

[0063] Based on any of the aforementioned solutions, in one possible implementation, the system further includes a backup fuel shut-off valve, which is used for on-off control of the fuel supply pipeline.

[0064] In this solution, the standby fuel shut-off valve serves as a backup for the main fuel shut-off valve. When the main valve fails, it can take over its work in time to ensure normal on-off control of the fuel supply pipeline, so that the engine can continue to operate stably, reduce the risk of test interruption, and improve test efficiency and safety.

[0065] In this solution, the spare shut-off valve can have the same specifications and performance parameters as the fuel shut-off valve to ensure that it can provide the same flow control and sealing performance when replacing the main valve.

[0066] The backup fuel shutoff valve should be connected in parallel with the main fuel shutoff valve on the fuel supply line. In this way, under normal circumstances, only the main valve is working and the backup valve is closed; when the main valve fails, the backup valve can be quickly opened to take over the work of the main valve.

[0067] In this solution, the drive circuit for the backup fuel shutoff valve should be independent of the drive circuit for the main valve, but both should be connected to the output port of the controller. This way, the controller can control the opening and closing of the main valve and the backup valve separately.

[0068] In this solution, when a fault is detected in the main fuel shut-off valve, the main fuel shut-off valve is controlled to be closed, and then the backup fuel shut-off valve is opened to ensure normal on-off of the fuel supply pipeline.

[0069] In this solution, by setting up a backup fuel shut-off valve, the problem of abnormal fuel supply caused by a fault during engine operation (such as solenoid valve sticking, damage, etc.) can be avoided, and the normal operation of the engine can be ensured.

[0070] The controller is further configured to obtain a detection current of the fuel cut-off valve, and control the backup cut-off valve to open when the detection current is abnormal.

[0071] In this solution, a current detection circuit may be configured in the detection system, and the current detection circuit is used to detect the current value of the fuel cut-off valve in real time.

[0072] In this solution, a reasonable threshold can be set based on the fuel shutoff valve current range under normal operating conditions. When the detected current value exceeds this threshold, the solenoid valve is considered abnormal. For example, for a solenoid valve with a normal operating current range of 1 to 2A, a current value less than 1A or greater than 2A is considered abnormal.

[0073] The configuration controller receives the current signal of the current detection circuit by means of the communication interface, and immediately generates an instruction to open the standby fuel shut-off valve when it finds that the current of the coil of the currently used fuel shut-off valve is abnormal.

[0074] This solution uses real-time fuel shutoff valve detection current to identify faults and automatically open the backup shutoff valve. This process is rapid and requires minimal human intervention. Compared to manual valve switching after a fault is discovered during a manual inspection, this solution significantly shortens fault response time, enabling immediate resolution of fuel shutoff valve failures, minimizing the impact of the fault on engine operation, improving system troubleshooting efficiency, and reducing downtime and maintenance costs associated with the fault.

[0075] Based on any of the foregoing schemes, in one feasible implementation scheme, the controller is further configured to obtain the detection current of the nitrogen shut-off valve, the nitrogen breather valve, the vent solenoid valve, and the discharge solenoid valve, and generate an alarm prompt message when any detection current is abnormal.

[0076] In this solution, in addition to current monitoring of the fuel shut-off valve and backup valve switching control, it is equally important to monitor the working status of the nitrogen shut-off valve, nitrogen breather valve, bleed solenoid valve, and discharge solenoid valve in real time.

[0077] By acquiring the test currents of these valves and generating an alarm when any valve current anomaly is detected, the system can promptly identify potential valve faults (such as solenoid valve sticking, coil damage, etc.). This timely alarm allows operators to take prompt action to avoid problems such as engine malfunction, fuel leakage, and pressure loss caused by valve failure, thereby ensuring safe engine operation and improving system reliability and maintainability.

[0078] In this solution, each nitrogen shut-off valve, nitrogen breather valve, purge solenoid valve, and discharge solenoid valve can be equipped with an independent current detection sensor. The current detection sensor can be a Hall effect current sensor or a resistive current sensor.

[0079] In this solution, when the controller detects an abnormal current flow in a valve, it triggers an alarm handler. This handler generates appropriate alarm information, such as the valve number and fault type (excessive or insufficient current), and displays the alarm on the display or activates an audible or visual alarm. The alarm information is also recorded in a log file for subsequent fault analysis and troubleshooting.

[0080] exist Figure 1 On the basis of the illustrated solution, in one possible implementation scheme, the nitrogen shut-off valve includes a first nitrogen shut-off valve and a second nitrogen shut-off valve.

[0081] The first nitrogen stop valve and the second nitrogen stop valve are arranged in series, and the nitrogen breathable valve is arranged on the pipeline between the first nitrogen stop valve and the second nitrogen stop valve; the first nitrogen stop valve and the second nitrogen stop valve have the same on-off state.

[0082] In this solution, the detection system is equipped with two nitrogen shut-off valves to avoid the risk of nitrogen leakage due to the degradation of sealing performance of a single valve after long-term use due to wear, aging, etc.

[0083] The first nitrogen shut-off valve and the second nitrogen shut-off valve are set in series. When one of the valves leaks slightly, the other valve can still effectively prevent further leakage of nitrogen, greatly reducing the safety hazards caused by nitrogen leakage and ensuring the safety of the test environment and the stable operation of the engine system.

[0084] The nitrogen vent valve is installed in the pipeline between the first and second nitrogen shut-off valves, working in conjunction with the two shut-off valves to effectively manage nitrogen within the system. To release nitrogen from the pipeline, close both nitrogen shut-off valves and then open the nitrogen vent valve to expel any remaining nitrogen between the two shut-off valves, preventing it from impacting subsequent operations. During the pressure maintenance phase, the nitrogen vent valve remains closed to prevent nitrogen from leaking through the vent valves and maintain stable system pressure.

[0085] Based on any of the above schemes, in one possible implementation scheme, the initial states of the fuel shut-off valve, the nitrogen shut-off valve, the purge solenoid valve, and the discharge solenoid valve are set to be closed, and the initial state of the nitrogen breather valve is set to be open.

[0086] In this solution, when entering the dual-fuel mode, the air bleed solenoid valve and the fuel shut-off valve are controlled to open; after entering the dual-fuel mode, it is determined whether the difference between the fuel filter pressure and the fuel supply pressure is less than a preset threshold. If so, the air bleed solenoid valve is controlled to close.

[0087] In this solution, the fuel post-filter pressure refers to the pressure of the fuel after it passes through the filter in the supply tank and before it enters the fuel shut-off valve.

[0088] In this embodiment, the fuel supply pressure refers to the pressure of the fuel immediately before it enters the engine after passing through the fuel shut-off valve.

[0089] In this solution, the purpose of judging the pressure difference between the fuel filter pressure and the fuel supply pressure is to see whether there is still nitrogen in the supply pipeline. The nitrogen in the pipeline is discharged through the fuel supply. After confirming that it is completely discharged, the bleed solenoid valve is closed.

[0090] For example, in this solution, a pressure sensor can be installed on the fuel supply line near the engine's air intake to measure the fuel supply pressure; a pressure sensor can be installed at the fuel filter outlet to measure the fuel pressure after filtration. These two sensors should be selected with appropriate range and accuracy based on the engine's operating pressure range to ensure reliable measurement data.

[0091] In this solution, the outputs of the two pressure sensors are connected to the analog input port of the controller via shielded cables. The analog input channel of the controller reads the voltage signal output by the pressure sensors, converts it into the actual pressure value, and stores it in the controller's memory.

[0092] In this solution, a preset threshold is set in the controller program based on the engine's technical specifications and experimental data. This threshold can be a fixed value.

[0093] In this solution, the controller can be configured to first send an open signal to the output ports corresponding to the air bleed solenoid valve and the fuel shut-off valve when receiving the instruction to enter the dual-fuel mode, and last for a certain period of time (such as 5 to 10 seconds) to ensure that the pipeline cleaning and fuel preparation work are completed.

[0094] In addition, sensor data is used to monitor pipeline pressure and gas emissions. If the expected status is not reached within the specified time, an alarm will be issued to prompt the operator to check the system.

[0095] In this solution, during operation in dual-fuel mode, the engine operating parameters (such as speed, power, etc.) and fuel supply parameters (such as pressure, flow, etc.) are continuously monitored, and the opening of the fuel shut-off valve (if the valve has an opening adjustment function) is fine-tuned according to actual conditions to ensure stable engine operation.

[0096] In this scheme, when exiting the dual-fuel mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to open, and the nitrogen breather valve, the fuel shut-off valve, and the bleed solenoid valve are controlled to close; 20 seconds after exiting the dual-fuel mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to close, and the bleed solenoid valve and the nitrogen breather valve are controlled to open; 25 seconds after exiting the dual-fuel mode, the bleed solenoid valve is controlled to close.

[0097] In this solution, upon receiving a command to exit dual-fuel mode, the controller sends control signals to the corresponding output ports of the bleed solenoid valve, nitrogen shutoff valve, nitrogen vent valve, fuel shutoff valve, and bleed solenoid valve. Control is performed in a specific time sequence.

[0098] For example, first open the nitrogen shut-off valve and the discharge solenoid valve, and close the other valves for a period of time (such as 10 to 20 seconds) to discharge the residual liquid fuel; then, control the discharge solenoid valve and the nitrogen shut-off valve to close, and control the bleed solenoid valve and the nitrogen breather valve to open for a period of time (such as 5 seconds) to allow the gas in the system to circulate further, ensuring that the nitrogen fully replaces the residual fuel gas and ensuring the safety of the gas composition in the system; then, control the bleed solenoid valve to close. By controlling the bleed solenoid valve, the degree of gas emission can be accurately controlled to prevent excessive exhaust from causing the system pressure to be too low or introducing too much air, thereby ensuring that the system is in a safe and stable gas environment and pressure state.

[0099] Based on any of the foregoing schemes, in one feasible implementation scheme, when entering the pressure maintaining mode, the nitrogen shut-off valve is controlled to be open, the nitrogen breather valve is closed, and the remaining valves are kept consistent with their corresponding initial states (the initial states of the fuel shut-off valve, nitrogen shut-off valve, purge solenoid valve, and bleed solenoid valve are set to be closed, and the initial state of the nitrogen breather valve is set to be open).

[0100] In this solution, the purpose of controlling the operation of the nitrogen shutoff valve and nitrogen breather valve during pressure-maintaining mode is to establish and maintain a stable pressure environment for system leak testing. Closing the fuel shutoff valve prevents fuel from entering the system and interfering with pressure testing. Opening the nitrogen shutoff valve injects nitrogen into the system, raising the system pressure to a predetermined value. Closing the nitrogen breather valve prevents nitrogen leakage, ensuring stable system pressure and enabling accurate determination of leaks.

[0101] Based on any of the foregoing schemes, in one possible implementation scheme, when entering the pressure relief mode, the air release solenoid valve and the nitrogen breather valve are controlled to open, and the other valves are closed; 20 seconds after entering the pressure relief mode, the air release solenoid valve is controlled to close.

[0102] When in pressure relief mode, the bleed solenoid valve is controlled to open, primarily to safely reduce system pressure. Closing the fuel shutoff valve prevents accidental fuel leaks during the pressure relief process. Opening the bleed solenoid valve provides a discharge path for nitrogen in the system, gradually reducing pressure to a safe level and preventing damage to equipment or accidents caused by excessive pressure.

[0103] In this solution, connect the control terminals of the fuel shutoff valve, nitrogen shutoff valve, nitrogen vent valve, and bleed solenoid valve to the controller's output ports. Ensure that the connections are secure and free of shorts or breaks. Install a pressure sensor at a suitable location in the system piping to monitor system pressure in real time. Connect the pressure sensor's output to the controller's analog input port.

[0104] When the system receives the instruction to enter the pressure maintaining mode, the controller performs the following operations according to the preset program: sends a closing signal to the control ports of the fuel shut-off valve, nitrogen breather valve, bleed solenoid valve and discharge solenoid valve, and sends an opening signal to the control port of the nitrogen shut-off valve.

[0105] When in pressure-holding mode, the pressure monitoring program is activated, and the pressure sensor acquires real-time system pressure data. If the pressure reaches the predetermined holding value and remains stable for a period of time (pressure fluctuations within the allowable range within 1 minute), the pressure-holding test is considered passed. If the pressure continues to drop and exceeds the allowable fluctuation range, a leak alarm is issued, prompting the operator to check the system.

[0106] When the system needs to enter pressure relief mode, the controller sends a closing signal to the nitrogen shutoff valve and an opening signal to the bleed solenoid valve and nitrogen breather valve. During the pressure relief process, the controller continuously monitors the pressure sensor data and adjusts the opening of the bleed solenoid valve (if the valve has an opening adjustment function) according to the pressure drop to ensure a steady pressure drop. When the pressure drops to a safe value, the bleed solenoid valve closes, completing the pressure relief operation.

[0107] Based on any of the aforementioned solutions, in one possible implementation, when entering the purge mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to open, and the remaining valves are controlled to close.

[0108] In this solution, when entering purge mode, the drain solenoid valve opens to discharge residual liquid fuel, ensuring that liquid fuel does not accumulate in the pipeline. After the nitrogen shut-off valve is opened, nitrogen is introduced to purge the pipeline using its inert and clean properties.

[0109] Nitrogen can remove residual fuel and impurities in the pipeline, playing a cleaning role. The nitrogen breather valve and bleed solenoid valve are closed to ensure pressure balance in the pipeline, allowing the purge process to proceed smoothly, effectively removing residual substances in the pipeline and ensuring the safety and normal operation of the engine system.

[0110] When the system receives the instruction to enter the purge mode, it simultaneously sends an open signal to the nitrogen shut-off valve and the bleed solenoid valve, and a close signal to the fuel shut-off valve, the nitrogen breather valve and the bleed solenoid valve. In the purge mode, the liquid fuel in the engine and the pipeline is purged to a designated location (such as a liquid fuel storage tank).

[0111] During the purge process, the controller uses a pressure sensor to monitor pressure changes in the pipeline in real time. Based on these pressure changes, the controller adjusts the opening of the nitrogen shutoff valve (if the valve has an opening adjustment function) to maintain the appropriate purge pressure. If the pressure is too high, the nitrogen shutoff valve opening is appropriately reduced; if the pressure is too low, the opening is appropriately increased.

[0112] The purge process is complete when the purge time reaches the preset value, or when the pressure sensor detects that the pressure in the pipeline is stable within a safe range. Upon completion, the nitrogen shutoff valve is closed, and the nitrogen vent valve and bleed solenoid valve are opened. This releases nitrogen from the pipeline to the atmosphere. After 30 seconds, the controller automatically sends a command to close the bleed solenoid valve. Figure 2 is another schematic diagram of the structure of an engine detection system in an embodiment, Figure 3 is a schematic diagram of the detection logic in the embodiment, Figure 4 This is a schematic diagram of the valve assembly circuit in the embodiment, refer to Figures 2 to 4 Based on any of the above solutions, in one possible implementation scheme, the engine detection system includes:

[0113] The fuel cut-off valve 11 , the backup fuel cut-off valve 111 , the first nitrogen cut-off valve 121 , the second nitrogen cut-off valve 122 , the nitrogen breather valve 13 , the purge solenoid valve 14 , the drain solenoid valve 15 and the controller 1000 .

[0114] The fuel cut-off valve 11, the backup fuel cut-off valve 111, the first nitrogen cut-off valve 121, and the second nitrogen cut-off valve 122 are provided at the fuel inlet of the engine 1. The purge solenoid valve 14 and the drain solenoid valve 15 are provided at the fuel outlet of the engine 1.

[0115] The first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122 are arranged in series. The nitrogen permeation valve 13 is arranged on the pipeline between the first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122.

[0116] The fuel shutoff valve 11 and the backup fuel shutoff valve 111 are provided in parallel.

[0117] In this solution, the fuel shut-off valve 11, the backup fuel shut-off valve 111, the first nitrogen shut-off valve 121, the second nitrogen shut-off valve 122, the purge solenoid valve 14, and the discharge solenoid valve 15 are of the normally closed type, and the nitrogen breather valve 13 is of the normally open type.

[0118] Specifically, in this solution, the fuel cut-off valve 11 is connected to the fuel supply pipeline to control the supply of fuel and is connected to the normally open contact of the KA1 relay. When the coil is not powered, the valve is closed.

[0119] The standby fuel shut-off valve 111 is connected to the fuel supply line to control the fuel supply and is connected to the normally open contact of the KA11 relay. When the coil is not powered, the valve is closed.

[0120] One end of the first nitrogen cut-off valve 121 is connected to the nitrogen supply pipeline, and the other end is connected to the second nitrogen cut-off valve 122; one end of the second nitrogen cut-off valve 122 is connected to the first nitrogen cut-off valve 121, and the other end is connected to the engine fuel inlet pipeline.

[0121] The first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122 control the nitrogen supply. The first nitrogen shut-off valve 121 is connected to the normally open contact of the KA2 relay. When the coil is not powered, the valve is closed. The second nitrogen shut-off valve 122 is connected to the normally open contact of the KA3 relay. When the coil is not powered, the valve is closed.

[0122] One end of the nitrogen permeation valve 13 is connected between the first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122. The other end is connected to the atmosphere outside the factory through a pipeline to control the nitrogen in the exhaust pipeline. It is connected to the normally open contact of the KA4 relay. When the coil is not powered, the valve is open.

[0123] The bleed solenoid valve 14 is connected to the engine at one end and to the fuel recovery line at the other end to control the discharge of unburned gas fuel. It is connected to the normally open contact of the KA5 relay. When the coil is not powered, the valve is closed.

[0124] The discharge solenoid valve 15 is connected to the engine at one end and to the fuel recovery line at the other end, controlling the discharge of unburned liquid fuel. It is connected to the normally open contact of the KA6 relay. When the coil is not powered, the valve is closed.

[0125] In this solution, the controller places the fuel shut-off valve, nitrogen shut-off valve, nitrogen breather valve, vent solenoid valve, and discharge solenoid valve into designated on-off states, so that the detection system is placed in pressure maintaining mode, pressure relief mode, dual fuel mode, purge mode, and reset mode in sequence.

[0126] When the controller controls the solenoid valve to put the detection system into a certain mode, the switch status of each solenoid valve will change after a period of time. The controller can start timing after sending the command, and when the timing reaches the specified time, send the changed detection instruction to control the switch of each solenoid valve in the valve group unit.

[0127] In this solution, before the engine enters the dual-fuel mode, first check whether the pipeline can maintain pressure, control the opening of the first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122, close the nitrogen breather valve 13, and close the other valves to check whether there is any leakage and whether the pressure can be maintained.

[0128] After checking that the pressure is normal, start to release the pressure, close the first nitrogen stop valve 121 and the second nitrogen stop valve 122, open the nitrogen breather valve 13 and the vent solenoid valve 14, and release the nitrogen in the pipeline. After 30 seconds of pressure relief, close the vent solenoid valve 14.

[0129] In this solution, the engine starts to enter the dual fuel mode, and the fuel (formaldehyde) cut-off valve 11 and the air release solenoid valve 14 are opened to supply fuel to the engine.

[0130] When exiting the dual fuel mode, close the fuel shut-off valve 11, open the first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122, close the nitrogen breather valve 13, open the discharge solenoid valve 15, and deliver nitrogen to the pipeline.

[0131] 20 seconds after exiting dual fuel mode, close the first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122, open the nitrogen vent valve 13, open the vent solenoid valve 14, and close the bleed solenoid valve 15. 50 seconds after exiting dual fuel mode, return all valves to their initial states.

[0132] In this solution, the detection information is a hexadecimal value, and the controller determines which mode to enter and how to control the corresponding solenoid valve based on the value of the received detection information.

[0133] For example, corresponding to the pressure relief mode, the detection information is 0x10. After the controller receives this information, the DO5 channel outputs a low-level signal, and the DO1, DO2, DO3, DO4, and DO6 channels output high-level signals. After the relay group receives the signal, the relay coil KA5 is energized, thereby opening the air release solenoid valve.

[0134] After 20 seconds, the detection information changes to 0x00. After the controller receives this information, all digital output channels output high-level signals, all relay coils are closed, nitrogen permeability valve 13 is opened, and the other solenoid valves are closed.

[0135] Corresponding to the pressure holding mode, the detection information is 0x0E. After receiving this information, the controller controls the on / off status of each coil of the relay group, and then controls the on / off status of each solenoid valve of the solenoid valve group.

[0136] Corresponding to exiting the dual-fuel mode, the detection information is 0x2E. After the controller receives this information, the DO2, DO3, DO4, and DO6 channels output low levels, and DO1 and DO5 output high-level signals, thereby energizing the relay coils KA2, KA3, KA4, and KA6, and de-energizing KA1 and KA5, thereby controlling the valve group unit fuel cut-off valve 11 to close, the first nitrogen cut-off valve 121 and the second nitrogen cut-off valve 122 to open, the nitrogen breathable valve 13 to close, and the discharge solenoid valve 14 to open, to purge and discharge the fuel in the engine supply pipeline with nitrogen for 20 seconds.

[0137] 20 seconds later, the detection information is 0x10. After the controller receives this information, DO5 outputs a low-level signal, other channels output high-level signals, relay coil KA5 is powered on, and other relay coils are powered off, thereby controlling the first nitrogen shut-off valve 121 and the second nitrogen shut-off valve 122 to close, the nitrogen breathable valve 13 to open, the discharge solenoid valve 15 to close, and the vent solenoid valve 14 to open.

[0138] After 5 seconds, the detection information is 0x00. After the controller receives this information, all output channels output high level, all relay coils are de-energized, and the deflation solenoid valve 14 is controlled to be closed.

[0139] In this solution, for each mode, the solenoid valve state and the corresponding detection instructions for each control process can be shown in Table 1.

[0140] Table 1

[0141]

[0142]

[0143] In this solution, the detection system is further configured with a backup fuel cut-off valve 111 and a current detection circuit, which can detect the coil current value of each solenoid valve.

[0144] The controller can receive the coil current value and analyze the coil current value to determine whether each solenoid valve has an abnormality. If the coil current of the currently used fuel cut-off valve is found to be abnormal, the backup fuel cut-off valve 111 is immediately opened to supply fuel to the engine to ensure normal operation of the engine.

[0145] When the controller detects that the coil current values of several other solenoid valves are abnormal, it generates corresponding fault reminder information.

[0146] In this solution, the detection system can not only accurately control the switches of each solenoid valve in the valve group unit, but also accurately control the on and off of the solenoid valve in time, and automatically control the change of the switch state of the solenoid valve in the valve group unit without human operation in a certain process.

[0147] The detection system is capable of detecting and handling solenoid valve failures. It can determine given parameter conditions and, accordingly, determine and control the on / off switching of the solenoid valves. Once a solenoid valve failure is detected, the system will issue an alarm. Especially when a critical solenoid valve (such as the fuel shutoff valve) fails, the software automatically switches to the backup solenoid valve without engine shutdown or manual intervention, ensuring the normal fuel supply and maintaining normal engine operation.

[0148] The use of this detection system can greatly ensure the smooth progress of alternative fuel engine research and development tests, effectively save manpower and material resources, and at the same time avoid the safety risks faced by test personnel due to exposure to toxic alternative fuels, effectively ensuring the personal safety of test personnel.

[0149] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. An engine detection system, characterized in that: include: Fuel shut-off valve, nitrogen shut-off valve, nitrogen breather valve, bleed solenoid valve, discharge solenoid valve and controller; The fuel shut-off valve is used for on-off control of the fuel supply pipeline, the nitrogen shut-off valve is used for on-off control of the nitrogen pipeline, the nitrogen breather valve is used for on-off control of the nitrogen discharge pipeline, the purge solenoid valve is used for on-off control of the gas fuel discharge pipeline, and the discharge solenoid valve is used for on-off control of the liquid fuel discharge pipeline; The controller is configured to obtain a detection instruction, wherein the detection instruction is used to control the fuel shut-off valve, the nitrogen shut-off valve, the nitrogen breather valve, the purge solenoid valve, and the discharge solenoid valve to be placed in a specified on-off state respectively; The designated on-off state corresponds to one of a pressure maintaining mode, a pressure relief mode, entering a dual fuel mode, exiting a dual fuel mode, a purge mode, and a reset mode.

2. The engine detection system according to claim 1, wherein: It also includes a spare fuel shut-off valve, which is used for on-off control of the fuel supply pipeline; The controller is further configured to obtain a detection current of the fuel cut-off valve, and control the backup cut-off valve to open when the detection current is abnormal.

3. The engine detection system according to claim 1, wherein: The nitrogen stop valve includes a first nitrogen stop valve and a second nitrogen stop valve; The first nitrogen shut-off valve and the second nitrogen shut-off valve are arranged in series, and the nitrogen breathable valve is arranged on the pipeline between the first nitrogen shut-off valve and the second nitrogen shut-off valve; The on-off states of the first nitrogen shut-off valve and the second nitrogen shut-off valve are the same.

4. The engine detection system according to claim 2, wherein: The controller is further configured to obtain detection currents of the nitrogen shut-off valve, nitrogen breather valve, deflation solenoid valve, and discharge solenoid valve, and generate an alarm prompt message when any of the detection currents is abnormal.

5. The engine detection system according to claim 1, wherein: The initial states of the fuel shut-off valve, nitrogen shut-off valve, purge solenoid valve, and discharge solenoid valve are set to be closed, and the initial state of the nitrogen breathable valve is set to be open.

6. The engine detection system according to claim 5, characterized in that: When entering the dual fuel mode, the air release solenoid valve, the fuel shut-off valve, and the nitrogen breather valve are controlled to open, and the discharge solenoid valve and the nitrogen shut-off valve are controlled to close; After entering the dual fuel mode, it is determined whether the difference between the fuel filter pressure and the fuel supply pressure is less than a preset threshold. If so, the air release solenoid valve is controlled to close.

7. The engine detection system according to claim 5, characterized in that: When exiting the dual fuel mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to open, and the nitrogen breather valve, the fuel shut-off valve, and the bleed solenoid valve are controlled to close; 20 seconds after exiting the dual fuel mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to close, and the vent solenoid valve and the nitrogen breather valve are controlled to open; 25 seconds after exiting the dual fuel mode, the purge solenoid valve is controlled to close.

8. The engine detection system according to claim 5, wherein: When entering the pressure maintaining mode, the nitrogen shut-off valve is controlled to open and the other valves are closed.

9. The engine detection system according to claim 5, wherein: When entering the pressure relief mode, the air release solenoid valve and the nitrogen breather valve are controlled to open, and the other valves are closed; After entering the pressure relief mode for 20 seconds, the air release solenoid valve is controlled to close.

10. The engine detection system according to claim 5, characterized in that: When entering the purge mode, the discharge solenoid valve and the nitrogen shut-off valve are controlled to open, and the air release solenoid valve, the nitrogen breathable valve, and the fuel shut-off valve are controlled to close.

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