Ignition method and device for pure ammonia engine of vehicle

Abstract

The ignition method and device are applied to a vehicle, the vehicle comprises the pure ammonia engine and a motor, the pure ammonia engine comprises a variable valve timing device, and the method comprises the steps that if a pure ammonia engine starting instruction is received, the motor is controlled to drive the pure ammonia engine to the preset rotating speed, and the rotating speed is maintained for the first preset time; after the first preset time is maintained, the variable valve timing device is controlled to enter a preset control state; ammonia injection control and ignition control are executed at the later stage of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine. According to the method, rapid and reliable starting of the pure ammonia engine in the hybrid power vehicle is achieved, meanwhile, the combustion process is optimized, and the energy efficiency and starting smoothness of the whole vehicle are improved.

Description

Technical Field

[0001] This invention relates to the field of hybrid vehicle and engine control technology, and in particular to a method and apparatus for igniting a pure ammonia engine in a vehicle. Background Technology

[0002] Currently, ammonia, as a clean fuel with the potential for zero carbon emissions, has significant application prospects in the field of internal combustion engines. Pure ammonia engines use ammonia as the sole fuel, and their combustion products are mainly nitrogen and water, which is considered one of the important technological pathways to achieve carbon neutrality in the transportation sector.

[0003] However, ammonia fuel itself presents inherent challenges in terms of combustion characteristics, such as its high auto-ignition temperature and slow flame propagation speed, making it difficult to reliably ignite and stably burn under engine cold start or low-load conditions. Current technologies for ignition control in ammonia engines are still in the exploratory stage, especially in hybrid vehicle applications. How to combine vehicle energy management with electric motor assistance capabilities to achieve rapid and reliable ignition of pure ammonia engines under complex operating conditions remains a pressing technical problem to be solved.

[0004] Some existing solutions attempt to improve ammonia ignition performance by modifying the ignition system or adding combustion improvers, but these methods often suffer from problems such as system complexity, increased costs, or worsened emissions. Furthermore, in hybrid power configurations, a systematic and mature control method has yet to be developed for how to coordinate the use of electric motor and engine control strategies to achieve an efficient and smooth start-up process for a pure ammonia engine. Summary of the Invention

[0005] In order to achieve rapid and reliable starting of the pure ammonia engine in hybrid vehicles, while optimizing the combustion process and improving the overall vehicle energy efficiency and starting smoothness, this invention provides a method and apparatus for igniting a pure ammonia engine in a vehicle.

[0006] In a first aspect, embodiments of the present invention provide a method for igniting a pure ammonia engine in a vehicle, applicable to a vehicle including a pure ammonia engine and an electric motor, the pure ammonia engine including a variable valve timing device, the method including: If a start command for the pure ammonia engine is received, the motor is controlled to drive the pure ammonia engine to a preset speed and maintain it for a first preset time. After maintaining the first preset time, the variable valve timing device is controlled to enter a preset control state; Ammonia injection control and ignition control are performed in the later stage of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine.

[0007] In one or more optional embodiments of this application, the variable valve timing device includes an intake variable valve timing device and an exhaust variable valve timing device. The control of the variable valve timing device to enter a preset control state includes: The advance angle of the intake variable valve timing device is controlled to be the maximum advance angle; The exhaust variable valve timing device is locked.

[0008] In one or more optional embodiments of this application, controlling the variable valve timing device to enter a preset control state further includes: The throttle valve of the variable valve timing device is controlled to open to its maximum opening.

[0009] In one or more optional embodiments of this application, the vehicle further includes an ammonia injection system and an ignition system. The step of performing ammonia injection control and ignition control during the later stages of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine includes: The ammonia injection system is controlled to inject ammonia gas during the later stage of the compression stroke of the pure ammonia engine. Control the ignition system to perform the ignition operation.

[0010] In one or more optional embodiments of this application, controlling the ammonia injection system to inject ammonia gas during the later stage of the compression stroke of the pure ammonia engine includes: If the pure ammonia engine is in the later stage of the compression stroke and the piston of the pure ammonia engine is within a preset angle range before top dead center, then the ammonia injection system is controlled to inject ammonia.

[0011] In one or more optional embodiments of this application, controlling the ignition system to perform an ignition operation includes: Based on the preset initial ignition advance angle, the ignition system is controlled to perform the ignition operation.

[0012] In one or more optional embodiments of this application, after igniting the pure ammonia engine, the following steps are further included: Use the preset initial ignition advance angle as the current ignition advance angle; The combustion performance data of the pure ammonia engine is obtained and used as the combustion performance data corresponding to the current ignition advance angle; Based on the current ignition advance angle and the preset learning step size, determine the next ignition advance angle; Ignition is performed based on the next ignition advance angle to obtain the combustion performance data corresponding to the next ignition advance angle; The optimal ignition advance angle is determined based on the combustion performance data corresponding to the current ignition advance angle and the combustion performance data corresponding to the next ignition advance angle. The optimized ignition advance angle is used as the current ignition advance angle. The process of determining the next ignition advance angle based on the current ignition advance angle and the preset learning step size is repeated until the optimal ignition advance angle is determined.

[0013] Secondly, embodiments of the present invention provide an ignition device for a vehicle's pure ammonia engine, which may include: The first control module is used to control the motor to drive the pure ammonia engine to a preset speed and maintain it for a first preset time if a pure ammonia engine start command is received. The second control module is used to control the variable valve timing device to enter a preset control state after the first preset time is maintained. The third control module is used to perform ammonia injection control and ignition control in the later stage of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine.

[0014] Thirdly, embodiments of the present invention provide a computer-readable storage medium having a computer program / instructions stored thereon, which, when executed by a processor, implements the above-described method for igniting a pure ammonia engine in a vehicle.

[0015] Fourthly, embodiments of the present invention provide a computer program product, including a computer program / instructions, which, when executed by a processor, implement the above-described method for igniting a pure ammonia engine in a vehicle.

[0016] Fifthly, embodiments of the present invention provide a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the above-described method for igniting a pure ammonia engine in a vehicle.

[0017] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following: This invention provides a method for igniting a pure ammonia engine in a vehicle. The method involves controlling an electric motor to drive the engine to a preset speed and maintain it for a first preset time. After maintaining this speed for the first preset time, a variable valve timing device is controlled in conjunction with the engine to optimize in-cylinder airflow and dynamic compression ratio, improving the stability of the air-fuel mixture. This provides a stable initial operating foundation for the pure ammonia engine, achieving optimal combustion conditions and effectively overcoming the cold-start difficulties caused by the high auto-ignition temperature and slow combustion speed of ammonia. Subsequently, ammonia injection and ignition control performed in the later stages of the compression stroke precisely match the combustion characteristics of ammonia, ultimately achieving reliable and stable ignition of the pure ammonia engine in a hybrid vehicle, significantly improving overall vehicle starting performance and energy efficiency.

[0018] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0019] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 A schematic flowchart of the ignition method for a pure ammonia engine in a vehicle provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the ignition device for a pure ammonia engine in a vehicle, provided in an embodiment of the present invention. Detailed Implementation

[0021] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0022] The inventors discovered that while some existing technologies attempt to improve ammonia ignition performance by modifying the ignition system or adding combustion improvers, these methods often suffer from system complexity, increased costs, or worsened emissions. Furthermore, in hybrid powertrain configurations, a systematic and mature control method has yet to be developed for the coordinated use of motor and engine control strategies to achieve an efficient and smooth start-up process for a pure ammonia engine. Based on this, the inventors, through further research and development, created this invention, providing a method and apparatus for igniting a pure ammonia engine in a vehicle.

[0023] Example 1 Embodiment 1 of the present invention provides a method for igniting a pure ammonia engine in a vehicle, applicable to a vehicle including a pure ammonia engine and an electric motor. The pure ammonia engine includes a variable valve timing device, as described above. Figure 1 As shown, the method may include the following steps S101-S103: S101: If a start command for the pure ammonia engine is received, control the motor to drive the pure ammonia engine to a preset speed and maintain it for a first preset time.

[0024] S102: After maintaining the first preset time, control the variable valve timing device to enter the preset control state.

[0025] S103: Performs ammonia injection control and ignition control in the later stage of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine.

[0026] This invention provides a method for igniting a pure ammonia engine in a vehicle. The method involves controlling an electric motor to drive the engine to a preset speed and maintain it for a first preset time. After maintaining this speed for the first preset time, a variable valve timing device is controlled in conjunction with the engine to optimize in-cylinder airflow and dynamic compression ratio, improving the stability of the air-fuel mixture. This provides a stable initial operating foundation for the pure ammonia engine, achieving optimal combustion conditions and effectively overcoming the cold-start difficulties caused by the high auto-ignition temperature and slow combustion speed of ammonia. Subsequently, ammonia injection and ignition control performed in the later stages of the compression stroke precisely match the combustion characteristics of ammonia, ultimately achieving reliable and stable ignition of the pure ammonia engine in a hybrid vehicle, significantly improving overall vehicle starting performance and energy efficiency.

[0027] To facilitate understanding by those skilled in the art, the hybrid power system comprising a pure ammonia engine described in this method is hereby fully described: To achieve stable application of ammonia fuel in hybrid vehicles, the hybrid system requires several dedicated or enhanced devices. The core feature of this system is the integration of a pure ammonia engine and an electric motor as two power sources, along with a matching dedicated fuel supply and control system. Specifically, the fuel supply typically employs an ammonia injection system, usually a port injection method. This allows ammonia to premix with fresh air in the intake manifold before entering the cylinder, contributing to the formation of a homogeneous mixture and laying the foundation for reliable ignition.

[0028] For ignition, a dedicated ignition system is configured. To meet the high ignition energy requirements of ammonia, this system is typically matched with a high-energy ignition coil, with an ignition energy usually designed to be above 120 millijoules, ensuring a strong spark sufficient to ignite the ammonia mixture under various operating conditions. Furthermore, the physical properties of ammonia fuel require the ammonia supply system to have a heating function. A dedicated ammonia heating device is generally configured to stably maintain the ammonia temperature within a suitable range of approximately 50 degrees Celsius. This helps improve the atomization and evaporation characteristics of ammonia, thereby enhancing the quality of the mixture.

[0029] At the control level of the pure ammonia engine itself, in order to optimize intake efficiency and in-cylinder airflow, the pure ammonia engine needs to be matched with a variable valve timing device, including an intake variable valve timing device and an exhaust variable valve timing device. This device can dynamically adjust the opening and closing times of the intake and exhaust variable valve timing devices, thereby achieving flexible control of charging efficiency, internal residual exhaust gas volume, and valve overlap angle under different engine operating conditions. This is particularly crucial for improving the combustion process of ammonia, a fuel with a relatively slow combustion speed.

[0030] As one of the core features of a hybrid powertrain, the vehicle's drive motor has the ability to tow the pure ammonia engine. This means that the motor can output torque under specific control commands, actively dragging the crankshaft of the pure ammonia engine to the required speed. This capability is crucial in the starting process described in this method, allowing the engine to be boosted to a high initial speed (e.g., above 2000 rpm) before ignition attempts begin. This not only enhances the intensity of airflow turbulence within the cylinder, facilitating the formation and propagation of the air-fuel mixture, but also creates conditions for establishing sufficient compression final temperature and pressure, thereby significantly improving the ignition success rate and initial combustion stability of the pure ammonia engine.

[0031] In step S101 above, if a start command for the pure ammonia engine is received, the motor is controlled to drive the pure ammonia engine to a preset speed and maintain it for a first preset time.

[0032] Specifically, when the vehicle's controller receives a start command for the ammonia engine from the vehicle or driver, the controller sends a control signal to the motor connected to the ammonia engine, instructing the motor to output drive torque. This torque is transmitted to the crankshaft of the ammonia engine through the transmission system, thereby overcoming the engine's static resistance and causing it to rotate. The control objective is to increase and stabilize the speed of the ammonia engine at a preset speed. The preset speed can be set, for example, to 1200 revolutions per minute.

[0033] Once the preset speed is reached, control of the motor will be maintained, allowing the ammonia engine to continue operating at this constant speed for a first preset time. This continuous operation for the first preset time aims to establish a stable thermodynamic and mechanical state for subsequent combustion control steps, such as stabilizing engine coolant and oil temperatures and ensuring adequate lubrication of all moving parts of the ammonia engine. By actively dragging and maintaining the speed with the motor, starting failures caused by unstable combustion at extremely low speeds in the ammonia engine are effectively avoided, creating the necessary conditions for reliable ignition of ammonia fuel. The first preset time can be set, for example, to 30 seconds.

[0034] In step S102 above, after maintaining the first preset time, the variable valve timing device is controlled to enter a preset control state. The variable valve timing device includes an intake variable valve timing device and an exhaust variable valve timing device. Specifically, it includes the following steps S1021-S1023: S1021: Control the advance angle of the intake variable valve timing device to the maximum advance angle.

[0035] Specifically, after the first preset time has elapsed, the pure ammonia engine controller sends a command to the phase controller of the intake variable valve timing device to adjust it to the design- or calibrated limit of advance, i.e., the maximum advance angle. For example, the phase of the intake camshaft is advanced by approximately 50 degrees of crankshaft rotation relative to the crankshaft position. This operation substantially increases the dynamic compression ratio of the pure ammonia engine while maintaining the geometric compression ratio unchanged. An earlier closing time of the intake variable valve timing device helps retain more air-fuel mixture in the cylinder at the beginning of the compression stroke, thereby increasing the in-cylinder temperature and pressure at the end of compression, which is crucial for improving the ignition reliability of ammonia, a fuel with a high auto-ignition temperature.

[0036] S1022: Controls the locking of the exhaust variable valve timing device.

[0037] Specifically, after the first preset time has elapsed, the pure ammonia engine controller simultaneously instructs the exhaust variable valve timing device to enter a locked state, i.e., to fix the phase of the exhaust camshaft, typically locking it at a reference position or minimum overlap angle position. The purpose of locking the exhaust variable valve timing device is to eliminate or significantly reduce the valve overlap angle when the intake and exhaust variable valve timing devices open simultaneously. Reducing the valve overlap angle effectively reduces short-circuit losses of fresh charge during scavenging, while also reducing the heating of the intake air by high-temperature residual exhaust gas, thereby increasing the actual amount of fresh air entering the cylinder. More importantly, the reduced tendency for the exhaust valve to open earlier results in a relatively longer residence time of the mixture in the cylinder during the compression stroke. This provides more time for further mixing of ammonia and air and subsequent flame propagation, helping to stabilize and improve the ammonia combustion process.

[0038] S1023: Controls the throttle valve of the intake variable valve timing device to open to its maximum opening.

[0039] Specifically, after the first preset time has elapsed, the pure ammonia engine controller simultaneously drives the throttle actuator associated with the variable valve timing device to rotate the throttle plate to the fully open position, achieving 100% opening. A fully open throttle minimizes flow resistance in the intake system, allowing air to enter the intake manifold more smoothly. In a pure ammonia engine driven by an electric motor with reciprocating piston motion, a fully open throttle helps utilize pressure fluctuations within the intake manifold to create an inertial boost effect, thereby increasing the instantaneous pressure within the intake manifold and improving its charging efficiency. Higher intake pressure and flow not only increase the oxygen content in the cylinder but also provide more favorable conditions for ammonia injection and premixing, ensuring a suitable and uniformly distributed combustible mixture is formed at ignition, thus improving ignition success rate and initial combustion stability.

[0040] In step S103 above, ammonia injection control and ignition control are performed in the later stage of the compression stroke of the pure ammonia engine to ignite the engine. The vehicle also includes an ammonia injection system and an ignition system. Specifically, this includes the following steps S1031-S1032: S1031: Controls the ammonia injection system to inject ammonia gas during the later stages of the compression stroke of a pure ammonia engine.

[0041] Specifically, if the pure ammonia engine is in the later stage of the compression stroke and the piston of the pure ammonia engine is within a preset angle range before top dead center, then the ammonia injection system is controlled to inject ammonia.

[0042] Specifically, the pure ammonia engine controller continuously monitors the crankshaft position sensor signal to accurately determine the real-time position of the piston in the cylinder. When it is determined that the engine is currently in the late stage of the compression stroke and the piston has moved to a preset angle range before the top dead center of the compression stroke, an opening command is sent to the ammonia injector of the ammonia injection system. The preset angle range can be set, for example, to 30±5 degrees, 30±2 degrees, etc.

[0043] Ammonia injection is performed within this preset angle range. After the ammonia enters the cylinder, it has enough time to mix with the high-temperature, high-pressure air that has already been compressed in the cylinder. At the same time, it avoids the risk of unwanted spontaneous combustion or incomplete chemical reaction of fuel during the compression process due to premature injection.

[0044] S1032: Controls the ignition system to perform ignition operations.

[0045] Specifically, it can be that the ignition system is controlled to perform ignition operations based on a preset initial ignition advance angle.

[0046] Specifically, after the ammonia injection is completed in step S1031 above, the pure ammonia engine controller triggers ignition according to a preset initial ignition advance angle. This preset initial ignition advance angle can be a calibration value, such as 20 degrees of crankshaft rotation before top dead center.

[0047] The crankshaft angle is continuously monitored. When the piston position is determined to reach the moment corresponding to the preset initial ignition advance angle, an ignition command is sent to the high-energy ignition coil of the ignition system. The ignition coil then generates a high-voltage arc on the spark plug of the corresponding cylinder, igniting the already formed ammonia-air mixture.

[0048] By controlling the ignition timing, the location of the combustion pressure peak can be optimized, placing it within the crankshaft angle range most favorable for the pure ammonia engine to perform its work. This ensures a smooth start-up transition and efficient initial combustion while igniting the pure ammonia engine. When the vehicle is used for the first time or if the optimal value has not been learned, this preset initial ignition advance angle will be used as the default value.

[0049] In this embodiment of the application, after performing the above step S103 to ignite the pure ammonia engine, step S104 may also be included, specifically including the following steps S1041-S1046: S1041: Use the preset initial ignition advance angle as the current ignition advance angle.

[0050] Specifically, the preset initial ignition advance angle in step S103 above can be used as the current ignition advance angle, serving as a reference value for ignition control and subsequent learning processes. The preset initial ignition advance angle can be exemplarily set to 20 degrees before top dead center.

[0051] S1042: Obtain the combustion performance data of the pure ammonia engine as the combustion performance data corresponding to the current ignition advance angle.

[0052] Specifically, after completing steps S101-S103 above to achieve ignition and combustion based on the current ignition advance angle, combustion performance data characterizing the combustion effect is collected and calculated in real time using an oxygen sensor or in-cylinder pressure sensor installed in the exhaust system of the pure ammonia engine. The combustion performance data specifically refers to the ratio of the actual air-fuel ratio to the stoichiometric air-fuel ratio. This ratio is usually represented by λ (lambda). A λ value of 1 represents the stoichiometric air-fuel ratio, a λ value greater than 1 indicates a lean mixture, and a λ value less than 1 indicates a rich mixture. By monitoring the λ value and its changing trend, it is possible to accurately assess whether the combustion of the mixture is complete, stable, and close to the theoretically optimal combustion state under the current ignition advance angle, thus providing a precise data foundation for optimizing the ignition advance angle.

[0053] S1043: Determine the next ignition advance angle based on the current ignition advance angle and the preset learning step size.

[0054] Specifically, one or two tentative angles adjacent to the current ignition advance angle can be generated based on a preset learning step size. For example, the preset learning step size can be set to 5 degrees. If the current ignition advance angle is 20 degrees before top dead center (TDC), then 25 degrees or 15 degrees before TDC may be determined as the next ignition advance angle for verification during the next startup.

[0055] S1044: Perform the ignition operation of steps S101-S103 above based on the next ignition advance angle to obtain the combustion performance data corresponding to the next ignition advance angle.

[0056] Specifically, when the vehicle receives the pure ammonia engine start command again, steps S101-S103 above, including controlling the motor to drive the pure ammonia engine, controlling the variable valve timing device to enter the preset control state, controlling ammonia injection, and controlling ignition, are executed. In step S1032, the next ignition advance angle determined in step S1043 (e.g., 15 degrees before top dead center) is used to perform the ignition operation. Similarly to step S1042, after the ignition operation based on the next ignition advance angle is completed, the combustion performance data corresponding to that next ignition advance angle is acquired and recorded.

[0057] S1045: Determine the optimal ignition advance angle based on the combustion performance data corresponding to the current ignition advance angle and the combustion performance data corresponding to the next ignition advance angle.

[0058] Specifically, this can involve comparing and analyzing two sets of data: the combustion performance data corresponding to the current ignition advance angle and the combustion performance data corresponding to the next ignition advance angle. That is, comparing the ratio of the actual air-fuel ratio to the theoretical air-fuel ratio corresponding to the current ignition advance angle and the next ignition advance angle, and selecting the ignition advance angle corresponding to the ratio closer to 1, which is then determined as the optimized ignition advance angle for the current learning cycle.

[0059] S1046: Using the optimized ignition advance angle as the current ignition advance angle, return to step S1043 above to determine the next ignition advance angle based on the current ignition advance angle and the preset learning step size, until the optimal ignition advance angle is determined through convergence.

[0060] Specifically, the optimized ignition advance angle determined in step S1045 can be updated to a new current ignition advance angle. Then, based on this new current ignition advance angle and the preset learning step size, a new next ignition advance angle can be determined for trial purposes, but previously tested ignition advance angles should be avoided.

[0061] For example, if the new current ignition advance angle is 20 degrees before top dead center (TDC), then the next ignition advance angle should be 25 degrees or 15 degrees before TDC. However, if an ignition operation has already been performed based on 15 degrees before TDC, and the determined optimized ignition advance angle is 20 degrees before TDC, then 25 degrees before TDC is selected as the new next ignition advance angle. Similarly, if the new current ignition advance angle is 15 degrees before TDC, then the next ignition advance angle should be 20 degrees or 10 degrees before TDC. However, if an ignition operation has already been performed based on 20 degrees before TDC, and the determined optimized ignition advance angle is 15 degrees before TDC, then 10 degrees before TDC is selected as the new next ignition advance angle.

[0062] By repeating this closed-loop process of "ignition-evaluation-optimization-retesting," after several startup cycles, the ignition advance angle that consistently optimizes combustion performance data can be identified. This angle is then converged and determined as the optimal ignition advance angle for the vehicle under current common operating conditions and stored in non-volatile memory for direct recall in subsequent startups. This self-learning process enables the vehicle control system to automatically adapt to engine wear, changes in fuel characteristics, and environmental differences, always maintaining optimal ignition timing.

[0063] In this embodiment of the application, in order to achieve adaptive and optimized control strategy and improve the convenience and consistency of repeated starts under different operating conditions, the method also includes a mechanism for storing and recalling combustion parameters. Specifically, a data processing and storage operation will be performed once before the vehicle finishes running and is ready to be powered off each time.

[0064] Data collected during this and previous startups and operations were analyzed and selected to identify a set of parameter combinations corresponding to the optimal combustion state. This set of parameters is defined as the optimal combustion parameter set, which comprehensively covers the key control variables affecting the ignition and combustion process. This set includes at least: the optimal ignition advance angle determined after convergence through the aforementioned ignition advance angle learning step; the throttle opening set during the startup phase to improve intake efficiency; the phase locked by the intake variable valve timing device and the exhaust variable valve timing device under preset control conditions; and the preset angle range used when performing injection in the later stages of the compression stroke.

[0065] This entire set of optimal combustion parameters is written into its internal non-volatile memory in the form of a data packet. When the vehicle receives the pure ammonia engine start command again, the controller will first read the previously saved optimal combustion parameter set from this non-volatile memory before or simultaneously with executing step S101. Subsequently, in the corresponding steps S102-S103, these stored parameter values ​​can be directly called to set the state of the variable valve timing device, throttle opening, preset angle range of ammonia injection, and optimal ignition advance angle, thereby skipping the initial exploration phase and directly applying the historically validated optimal control strategy. This mechanism not only ensures that a good combustion state can be quickly achieved with each cold start, improving the start success rate and consistency of driving experience, but also allows the control system to continuously accumulate operating experience, adapt to vehicle aging and environmental changes, and achieve long-term stable performance.

[0066] Example 2 Based on the same inventive concept, embodiments of the present invention also provide an ignition device for a vehicle pure ammonia engine, referring to... Figure 2 As shown, the device includes: The first control module 101 is used to control the motor to drive the pure ammonia engine to a preset speed and maintain it for a first preset time if a pure ammonia engine start command is received. The second control module 102 is used to control the variable valve timing device to enter a preset control state after the first preset time is maintained. The third control module 103 is used to perform ammonia injection control and ignition control in the later stage of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine.

[0067] Example 3 Based on the same inventive concept, embodiments of the present invention also provide a computer-readable storage medium storing a computer program / instructions thereon, which, when executed by a processor, implements the ignition method of a pure ammonia engine in a vehicle as described in Embodiment 1 above.

[0068] Example 4 Based on the same inventive concept, embodiments of the present invention also provide a computer program product, including a computer program / instruction, which, when executed by a processor, implements the ignition method of a pure ammonia engine in a vehicle as described in Embodiment 1 above.

[0069] Example 5 Based on the same inventive concept, this embodiment of the invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory. When the processor executes the computer program, it implements the ignition method of a pure ammonia engine in a vehicle as described in Embodiment 1 above.

[0070] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0071] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0072] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0073] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0074] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for igniting a pure ammonia engine in a vehicle, applied to a vehicle comprising a pure ammonia engine and an electric motor, the pure ammonia engine comprising a variable valve timing device, characterized in that, The method includes: If a start command for the pure ammonia engine is received, the motor is controlled to drive the pure ammonia engine to a preset speed and maintain it for a first preset time. After maintaining the first preset time, the variable valve timing device is controlled to enter a preset control state; Ammonia injection control and ignition control are performed in the later stage of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine.

2. The method according to claim 1, characterized in that, The variable valve timing device includes an intake variable valve timing device and an exhaust variable valve timing device; The control of the variable valve timing device to enter a preset control state includes: The advance angle of the intake variable valve timing device is controlled to be the maximum advance angle; The exhaust variable valve timing device is locked.

3. The method according to claim 2, characterized in that, The method of controlling the variable valve timing device to enter a preset control state further includes: The throttle valve of the variable valve timing device is controlled to open to its maximum opening.

4. The method according to claim 1, characterized in that, The vehicle also includes an ammonia injection system and an ignition system. The ammonia injection control and ignition control are performed during the later stages of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine, including: The ammonia injection system is controlled to inject ammonia gas during the later stage of the compression stroke of the pure ammonia engine. Control the ignition system to perform the ignition operation.

5. The method according to claim 4, characterized in that, The control of the ammonia injection system to inject ammonia gas during the later stage of the compression stroke of the pure ammonia engine includes: If the pure ammonia engine is in the later stage of the compression stroke and the piston of the pure ammonia engine is within a preset angle range before top dead center, then the ammonia injection system is controlled to inject ammonia.

6. The method according to claim 4, characterized in that, The control of the ignition system to perform the ignition operation includes: Based on the preset initial ignition advance angle, the ignition system is controlled to perform the ignition operation.

7. The method according to claim 6, characterized in that, After igniting the pure ammonia engine, the process also includes: Use the preset initial ignition advance angle as the current ignition advance angle; The combustion performance data of the pure ammonia engine is obtained and used as the combustion performance data corresponding to the current ignition advance angle; Based on the current ignition advance angle and the preset learning step size, determine the next ignition advance angle; Ignition is performed based on the next ignition advance angle to obtain the combustion performance data corresponding to the next ignition advance angle; The optimal ignition advance angle is determined based on the combustion performance data corresponding to the current ignition advance angle and the combustion performance data corresponding to the next ignition advance angle. The optimized ignition advance angle is used as the current ignition advance angle. The process of determining the next ignition advance angle based on the current ignition advance angle and the preset learning step size is repeated until the optimal ignition advance angle is determined.

8. An ignition device for a vehicle's pure ammonia engine, characterized in that, include: The first control module is used to control the motor to drive the pure ammonia engine to a preset speed and maintain it for a first preset time if a pure ammonia engine start command is received. The second control module is used to control the variable valve timing device to enter a preset control state after the first preset time is maintained. The third control module is used to perform ammonia injection control and ignition control in the later stage of the compression stroke of the pure ammonia engine to ignite the pure ammonia engine.

9. A computer-readable storage medium having a computer program / instructions stored thereon, characterized in that, When the computer program / instruction is executed by the processor, it implements the ignition method of the pure ammonia engine of the vehicle as described in any one of claims 1-7.

10. A computer device, comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the ignition method of the pure ammonia engine in a vehicle according to any one of claims 1-7.

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