Engine start control method and system

Abstract

This invention discloses an engine start-up control method and system. The method acquires engine oil temperature and speed information, identifies the engine's operating stage, and adjusts engine parameters and heats the engine in stages to initiate engine start-up based on the engine's operating stage and the oil temperature and speed information. The engine start-up control method and system of this invention perform stage-differentiated control during the engine start-up process, adjusting and using optimal engine parameters in stages, and ensuring rapid engine warm-up, effectively improving the cold start success rate and shortening the engine cold start time.

Description

Technical Field

[0001] This invention relates to the field of engine control technology, and in particular to an engine start control method and system. Background Technology

[0002] Due to the large molecular weight, high kinematic viscosity, high flash point, and low volatility of fuel, heavy oil engines for drones are difficult to ignite directly using traditional fuel-air premixing methods. Currently, most engines employ preheating or high-pressure injection to address this issue. However, current heavy oil engines for drones suffer from low cold-start success rates and inaccurate engine load control. Furthermore, existing preheating methods typically involve preheating the fuel outside the intake manifold. Because of the characteristics of heavy oil, even when atomized into tiny droplets during injection, these droplets must pass through the intake manifold and combustion chamber sequentially after entering the engine. During this process, the fuel temperature decreases, causing the droplets to re-condense and making it difficult to form a proper air-fuel mixture. This can lead to cylinder flooding after repeated starts, resulting in difficulty starting the engine in cold conditions. It also causes carbon buildup on the spark plugs, shortens the mean occupancy time (MAG) interval, affects the drone's environmental adaptability and operational efficiency, and reduces engine lifespan. Summary of the Invention

[0003] The technical problem to be solved and the technical task proposed by this invention is to improve the existing technology and provide an engine start control method to solve the problems of difficult cold start of the engine, which leads to carbon buildup on the spark plugs, shortened mean maintenance interval, and reduced service life.

[0004] To solve the above technical problems, the technical solution of the present invention is as follows:

[0005] An engine starting control method, comprising:

[0006] It acquires engine oil temperature and speed information to identify the engine's operating stage;

[0007] Based on the engine's operating stage and information on engine oil temperature and speed, the engine parameters are adjusted in stages, and the engine is heated in stages to start the engine.

[0008] Furthermore, the engine's operating time is obtained, and the engine's operating stage is identified based on the engine's operating time and engine speed information.

[0009] Furthermore, the engine's operating phases include a towing phase, a stable starting phase, and a warm-up phase;

[0010] When the drive motor starts to drive the engine and the running time is less than or equal to the preset running time, the engine is identified as being in the driving phase.

[0011] When the running time is greater than the preset running time and the engine speed is greater than zero, the engine is identified as being in a stable starting phase.

[0012] When the running time is greater than the preset running time and the engine speed fluctuation is less than the speed fluctuation tolerance value, the engine is identified as being in the warm-up stage.

[0013] Furthermore, the engine parameters include injection advance angle, ignition advance angle, injection pulse width, and throttle position angle. When the engine is in the drag phase, the injection advance angle is calculated according to a preset interpolation table one of injection advance angle with respect to oil temperature, the injection pulse width is calculated according to a preset interpolation table two of injection pulse width with respect to oil temperature, the ignition advance angle is set to a calibrated fixed value, and the throttle position angle is set to a preset fixed value.

[0014] Furthermore, the engine parameters include injection advance angle, ignition advance angle, injection pulse width, and throttle position angle. When the engine is in a stable starting phase, the injection advance angle is calculated according to a preset interpolation table of injection advance angle with respect to oil temperature, the injection pulse width is calculated according to a preset interpolation table of injection pulse width with respect to oil temperature, the ignition advance angle is adjusted according to the engine calibration data table, and the throttle position angle is maintained at a preset fixed value.

[0015] Furthermore, the engine parameters include injection advance angle, ignition advance angle, injection pulse width, and throttle position angle. When the engine is in the warm-up stage, the injection advance angle is calculated and weighted by a first interpolation table of injection advance angle with respect to oil temperature. The injection pulse width is calculated and weighted by a second interpolation table of injection pulse width with respect to oil temperature. The ignition advance angle is adjusted according to the engine calibration data table. The throttle position angle is adjusted to the idle speed target position.

[0016] Furthermore, when the engine is in the dragging phase, engine heating begins when the engine oil temperature is lower than a preset oil temperature value or the engine speed is lower than a preset speed value.

[0017] Maintain engine heating while the engine is in a stable starting phase;

[0018] When the engine is in the warm-up phase, the engine heating will stop when the engine oil temperature is higher than the preset oil temperature value and the engine speed is higher than the preset speed value.

[0019] Furthermore, the engine heating includes heating the engine combustion chamber and preheating the fuel and air injected into the engine.

[0020] An engine start control system, comprising:

[0021] A heating device is installed on the engine;

[0022] The data acquisition unit collects engine oil temperature and speed information;

[0023] The control unit receives engine oil temperature and speed information, identifies the engine's operating stage, processes the engine parameters and heating commands based on the engine's operating stage and oil temperature and speed information, controls the heating device to work through the heating commands, and sends the engine parameters to the engine to control engine start.

[0024] Furthermore, the acquisition unit includes an oil temperature sensor and a crankshaft position sensor. The oil temperature sensor is installed in the crankcase to acquire the oil temperature, and the crankshaft position sensor acquires the crankshaft speed to obtain the engine speed.

[0025] Furthermore, the control unit sends a heating command to the heating control module, which drives the heating device to work. The heating control module has at least two parallel connections between the control unit and the heating device.

[0026] Furthermore, it also includes a host computer connected to the control unit, which displays the engine's operating stage, engine parameters, and heating status.

[0027] Furthermore, the heating device is installed in the engine's air intake manifold.

[0028] Compared with the prior art, the advantages of this invention are:

[0029] The engine start control method and system described in this invention perform phase-differentiated control during the engine start process, adjusting and using the optimal engine parameters in stages during the start process, effectively improving the cold start success rate, shortening the engine cold start time, and ensuring rapid engine warm-up and stable operation.

[0030] It can reduce carbon buildup and wear, and extend engine life;

[0031] Heating is automatically controlled based on oil temperature and engine speed, and the heating control adopts a redundant configuration to avoid engine heating failure. The heating reliability is high, ensuring reliable engine start and also providing the possibility of engine restart in the air.

[0032] It has good human-machine interaction, which allows users to intuitively grasp the engine's operating stage, engine parameters, and heating status, making it convenient for personnel to operate and maintain. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating the process of identifying the engine operation stage in the engine start-up control method of the present invention.

[0034] Figure 2This is a schematic diagram of the engine start control method of the present invention;

[0035] Figure 3 This is a schematic diagram of the engine start control system of the present invention.

[0036] In the picture:

[0037] T is the engine running time, T L1 The preset running time is 1, where n is the engine speed and T is the time. L2 For the preset running time two, σ L2 For engine speed fluctuations, σ pre This is the tolerance value for speed fluctuation. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] The present invention discloses an engine start control method and system that performs phase-differentiated parameter control during the engine cold start process, thereby improving the cold start success rate, shortening the cold start time, reducing engine carbon buildup and wear, ensuring engine life, and exhibiting good environmental adaptability.

[0040] like Figure 1 and Figure 2 As shown, an engine start-up control method, particularly a cold start control method for a heavy oil engine of an unmanned aerial vehicle (UAV), includes the following steps:

[0041] It acquires engine oil temperature and speed information to identify the engine's operating stage;

[0042] Based on the engine's operating stage and information on engine oil temperature and speed, the engine parameters are adjusted in stages and the engine is heated in stages to start the engine.

[0043] Differentiated control is implemented during engine startup, setting optimal engine parameters according to different operating stages of the engine. Furthermore, the engine is heated in stages based on its operating stage, oil temperature, and RPM information, effectively improving the success rate of cold starts and shortening the cold start time.

[0044] Specifically, an oil temperature sensor is installed on the engine crankcase to monitor the oil temperature (i.e., the engine oil temperature), and a crankshaft position sensor is installed to monitor the crankshaft speed, which is the engine speed. Engine oil temperature and engine speed are important factors for stage-differentiated control. When the oil temperature is too low, the oil viscosity is high, which can easily lead to difficulty in starting the engine. Furthermore, UAVs using heavy oil engines have long ranges and fly at high altitudes, usually in lower temperature environments, which can further lead to low oil temperatures, making engine starting and operation even more difficult. Therefore, by monitoring engine oil temperature and engine speed, stage-differentiated control of the engine can be implemented, and the optimal engine parameters can be adjusted and used at each stage of the engine start-up process, thereby improving the success rate of cold starts and also making it possible to restart the engine in mid-air.

[0045] Furthermore, a heating device is installed on the engine to heat the engine, keeping the engine oil at a suitable temperature, reducing its viscosity, and ensuring smooth and reliable engine starting. Specifically, engine heating includes heating the engine combustion chamber and preheating the fuel-air mixture injected into the engine. Heating the engine combustion chamber improves combustion completeness, which is beneficial for rapid engine starting. Preheating the fuel-air mixture injected into the engine helps to form a mixture more quickly, which is beneficial for complete combustion, reduces carbon deposits, improves the success rate of engine cold starts, and shortens engine cold start time.

[0046] Typically, heavy-duty oil engines are started by first being driven by a motor. Once the engine ignites successfully and its speed increases, the motor disengages. Finally, the engine starts successfully when its speed stabilizes. In this embodiment, the engine's running time is acquired, and the engine's operating stages are identified and divided based on the running time and monitored engine speed information. Specifically, the process for identifying the engine's operating stages is as follows: Figure 1 As shown, the engine's operating phases include a towing phase, a stable starting phase, and a warm-up phase;

[0047] Upon receiving an engine start request signal, the drive motor activates to start the engine, and timing begins from this point. The engine running time T is less than or equal to a preset running time - T. L1 At that time, it can be identified that the engine is currently in the towing phase;

[0048] When the engine running time is greater than the preset running time by 1T L1 Furthermore, when the engine speed n is greater than zero, it is recognized that the engine is currently in the stable starting stage. During the stable starting stage, the drive motor and the engine are still in a state of not being disengaged. At this time, the engine has not been fully started, and the engine speed is lower than the stable speed after the engine has started.

[0049] When the running time is greater than the preset running time by 2T L2 And the engine speed fluctuation σ L2 Less than the speed fluctuation tolerance value σ pre When the engine is identified as being in the warm-up phase, the drive motor is disengaged from the engine, and the engine speed gradually decreases from its highest point to a stable state. The fluctuation in engine speed gradually decreases, and when the engine speed fluctuation σ... L2 Less than the speed fluctuation tolerance value σ pre This indicates that the engine speed has stabilized, meaning the engine has successfully started and reached a stable state.

[0050] The optimal engine parameters are adjusted according to the identified engine operating stage, including the injection advance angle, ignition advance angle, injection pulse width, and throttle position angle.

[0051] The angle of crankshaft rotation from top dead center when the engine injectors begin injecting fuel is called the injection advance angle. The size of the injection advance angle significantly affects the operation of heavy-duty fuel engines. An excessively large injection advance angle results in a longer combustion period, causing rough engine operation. Conversely, an excessively small injection advance angle leads to excessively delayed combustion, a decrease in maximum pressure, and a significant reduction in the thermal efficiency of the heavy-duty fuel engine. Therefore, to ensure good performance of a heavy-duty fuel engine, the optimal injection advance angle must be selected. The injection pulse width refers to the duration of each fuel injection controlled by the engine control unit (ECU). Since the fuel pressure in the engine's fuel system is constant, the fuel flow rate during injection is also constant. The injection quantity can only be controlled by the injection duration. Because electronic fuel injectors in electronic fuel injection engines are controlled by solenoid valves, and the engine speed is high with a very short injection time, the injection signal given by the ECU is a very brief pulse signal. The duration of this signal is the injection pulse width. The unit of measurement for fuel injection pulse width is milliseconds (ms). A larger value indicates a longer time for the injector to open and inject fuel, resulting in a richer air-fuel mixture. A smaller value indicates a shorter time for the injector to open and inject fuel, resulting in a leaner air-fuel mixture. There is no fixed standard for fuel injection pulse width; it generally varies with engine speed, load, and intake air volume. During engine operation, the ignition timing has a significant impact on engine performance. Advanced ignition means that the spark plug ignites the combustible mixture in the combustion chamber before the piston reaches top dead center of the compression stroke. The angle through which the crankshaft rotates from the ignition timing to the piston reaching top dead center is called the ignition advance angle. While the combustion of the air-fuel mixture in the cylinder has a certain speed—meaning it takes time for the combustible mixture to be completely burned from the spark plug ignition—the crankshaft can rotate a large angle in such a short time due to the high engine speed. If ignition occurs precisely when the piston reaches top dead center, the piston will have already begun to move downwards by the time the air-fuel mixture starts to burn, resulting in a decrease in engine power. Therefore, it is necessary to advance the ignition to ensure that the energy generated by the combustible mixture can be effectively utilized and to improve the engine's output power. Throttle position angle refers to the opening angle of the engine throttle. Different throttle position angles can change the engine's intake air volume, thereby controlling the engine's operation.

[0052] In this embodiment, the engine operation stages are identified and divided based on the engine's running time and engine speed. Optimized engine parameters are set and the engine is heated in different operation stages to improve engine starting efficiency and success rate, and shorten starting time. Specifically, the optimization settings for each engine operation stage are as follows:

[0053] 1) When the engine is identified as being in the driven phase, that is, from the start of the engine being driven by the drive motor until the engine running time is less than or equal to the preset running time:

[0054] The injection advance angle is calculated based on the preset injection advance angle interpolation table 1 with respect to oil temperature, and the injection pulse width is calculated based on the preset injection pulse width interpolation table 2 with respect to oil temperature. The ignition advance angle is set to a fixed calibration value, and the throttle position angle is set to a preset fixed value. Both the injection advance angle and the injection pulse width are adjusted in real time according to the oil temperature. The optimal setting parameters are selected to obtain the maximum output power and the minimum fuel consumption rate, improve combustion completeness, reduce carbon deposit production, promote stable engine speed increase, and shorten engine start time. The ignition advance angle and the throttle position angle adopt fixed optimal values ​​and do not need to be adjusted in real time with oil temperature or engine speed.

[0055] Furthermore, during engine operation, engine heating begins when the engine oil temperature is lower than a preset value or the engine speed is lower than a preset value. At lower oil temperatures, the oil viscosity is high, affecting engine starting efficiency. Heating the engine with a heating device allows it to heat up rapidly, thereby increasing the oil temperature quickly, reducing oil viscosity, and enabling smoother engine operation. This facilitates a rapid increase in engine speed, allowing the engine to reach a stable state more quickly and shortening engine start-up time. Specifically, engine heating includes heating the engine combustion chamber and preheating the fuel-air mixture injected into the engine. Heating the combustion chamber helps increase oil temperature and reduce viscosity, and also improves the completeness of fuel combustion in the combustion chamber, contributing to maximum power output. Preheating the fuel-air mixture injected into the engine allows for faster formation of the air-fuel mixture, improving combustion efficiency and completeness, increasing output power, and reducing fuel consumption.

[0056] 2) When the engine is identified as being in a stable starting phase, i.e., when the engine running time is greater than the preset running time and the engine speed is greater than zero:

[0057] The injection advance angle is calculated based on the preset injection advance angle interpolation table with respect to oil temperature (Table 1), and the injection pulse width is calculated based on the preset injection pulse width interpolation table with respect to oil temperature (Table 2). The ignition advance angle is adjusted according to the engine calibration data table. The throttle position angle is kept at a preset fixed value. The injection advance angle and injection pulse width are still adjusted in real time according to the oil temperature. The optimal setting parameters are selected to promote reliable engine starting. The throttle position angle is kept in the same state as in the drag phase and does not need to be adjusted to ensure sufficient intake air for complete combustion. When the gasoline engine maintains a constant throttle opening, speed, and air-fuel mixture concentration, the engine power and fuel consumption rate change with the ignition advance angle. There is an optimal ignition advance angle for each engine operating condition. The engine calibration data table on which the ignition advance angle is adjusted is an interpolation table of the ignition advance angle with respect to engine operating conditions. The ignition advance angle is adjusted to the optimal value in real time according to the engine operating conditions to improve engine output power and reduce fuel consumption rate.

[0058] Maintaining engine heating during the stable start-up phase involves keeping the heating device on the engine to heat the combustion chamber and preheat the fuel injected into the engine, thereby improving combustion completeness, increasing output power, reducing fuel consumption, and facilitating faster and more stable engine speed.

[0059] 3) When the engine is identified as being in the warm-up phase, i.e., the engine running time is greater than the preset running time and the engine speed fluctuation is less than the speed fluctuation tolerance value:

[0060] The injection advance angle is calculated and adjusted based on a preset interpolation table of injection advance angle with respect to oil temperature, and a weighted compensation value is applied. The injection pulse width is calculated and adjusted based on a preset interpolation table of injection pulse width with respect to oil temperature, and a weighted compensation value is applied. The ignition advance angle is adjusted according to the engine calibration data table. The throttle position angle is adjusted to the target idle speed position. The injection advance angle and injection pulse width are still adjusted in real time according to the oil temperature, but further precise corrections are made by weighting the compensation value during the warm-up phase to ensure that the injection advance angle and injection pulse width are set to the optimal parameter values, thereby ensuring engine performance. To maintain a stable condition, obtain maximum output power and minimum fuel consumption, the optimal value of the ignition advance angle is set in the same way as during the stable starting stage. Both are adjusted and set according to the engine calibration data table so that the ignition advance angle matches the real-time operating conditions of the engine. This allows the engine to do the most mechanical work per cycle. There is a time process from ignition and combustion of the air-fuel mixture to its complete combustion. The role of the optimal ignition advance angle is to ensure that the gas expansion tendency is at its maximum during the piston's downward stroke under various operating conditions. This results in the highest efficiency, the least vibration, the lowest temperature rise, and increases engine output power while reducing fuel consumption.

[0061] During the warm-up phase, when the engine oil temperature is higher than the preset oil temperature value and the engine speed is higher than the preset speed value, it means that the engine has been successfully started and reached a stable state. At this time, there is no need to heat the engine anymore. Turn off the heating device to stop engine heating. That is, stop heating the engine combustion chamber and stop preheating the fuel-air mixture injected into the engine. At this time, the engine oil temperature has risen to a stable state, the oil film in the cylinder-piston ring area is well covered, the engine runs well, and the temperature of the combustion chamber is also at a high level, which can ensure complete combustion of the air-fuel mixture. Therefore, there is no need to use the heating device to heat the engine anymore. Turning off the heating device can extend the service life of the heating device, improve its durability, and also reduce overall energy consumption.

[0062] like Figure 3 As shown, the starting control system based on the above engine starting control method mainly includes:

[0063] A heating device is installed on the engine to heat the engine;

[0064] The data acquisition unit collects engine oil temperature and speed information. Specifically, the data acquisition unit includes an oil temperature sensor and a crankshaft position sensor. The oil temperature sensor is installed in the crankcase to collect the oil temperature, and the crankshaft position sensor collects the crankshaft speed to obtain the engine speed.

[0065] The control unit receives engine oil temperature and speed information collected by the acquisition unit, identifies the engine's operating stage, and processes the engine parameters and heating commands based on the engine's operating stage, oil temperature, and speed information. The heating commands are then used to control the heating device to operate, and the engine parameters are sent to the engine to control engine startup.

[0066] The heating command issued by the control unit is processed by the signal amplification module and then sent to the heating control module. The heating control module drives the heating device to work. The heating control module has two parallel circuits between the control unit and the heating device, which adopts a redundant configuration and dual signal control of the heating device. If one heating control module fails, the other heating control module can still drive the heating device to work normally, ensuring that the engine heating does not fail and that the engine can heat up quickly, thereby improving the engine start success rate.

[0067] Specifically, the heating device is installed on the engine's intake manifold to heat the engine and preheat the fuel-air mixture injected into the engine. When the heating device is turned on, it keeps the engine intake manifold heated and the combustion chamber heated simultaneously. This preheats the fuel-air mixture injected into the engine, allowing for faster formation of the air-fuel mixture. The mixture burns more completely in the higher-temperature combustion chamber, thereby increasing power output and fuel efficiency. The heating device also rapidly raises the overall engine temperature, preventing the engine oil from remaining in a low-temperature, high-viscosity state. This facilitates the rapid formation of a well-covered oil film in the cylinder-piston ring area, enabling the engine to reach a stable operating state more quickly and improving engine start-up speed and success rate.

[0068] The engine start control system also includes a host computer connected to the control unit. The host computer communicates with the control unit via a CAN bus. The host computer displays the engine's operating stage, engine parameters, and heating status, providing good human-machine interaction. During the start-up process, it can intuitively display in real time the specific operating stage of the engine, as well as the engine parameters and heating status at that specific operating stage, facilitating personnel operation and maintenance.

[0069] The specific working process of the engine start control system described above is as follows: the control unit identifies and divides the engine's operating stage based on the engine's running time and the engine speed status collected by the crankshaft position sensor.

[0070] 1) Upon receiving an engine start request signal, the drive motor is turned on to drive the engine to start running, and timing begins. When the engine running time is less than or equal to the preset running time, the control unit recognizes that the engine is currently in the driving stage. Then, the control unit adjusts and sets the optimal engine parameters based on the current driving stage of the engine and the oil temperature collected by the oil temperature sensor at this time. The engine parameters include the injection advance angle, ignition advance angle, injection pulse width, and throttle position angle.

[0071] Specifically, the control unit calculates the real-time injection advance angle during the dragging phase based on a preset interpolation table of injection advance angle with respect to oil temperature (Table 1), and calculates the real-time injection pulse width during the dragging phase based on a preset interpolation table of injection pulse width with respect to oil temperature (Table 2). The ignition advance angle is set to a calibrated fixed value, and the throttle position angle is set to a preset fixed value. The control unit processes the optimal engine parameters and controls the engine operation during the dragging phase based on these optimal parameters to achieve maximum output power and minimum fuel consumption rate, improve combustion completeness, reduce carbon deposit formation, promote stable engine speed increase, and shorten engine start-up time. Simultaneously... The control unit processes the engine oil temperature and speed information to obtain a heating command. Specifically, when the engine oil temperature is lower than a preset oil temperature value or the engine speed is lower than a preset speed value, the control unit issues a heating command to start the heating. The heating command is sent to the heating control module, which drives the heating device to start to heat the engine, heating both the combustion chamber and the intake manifold. This preheats the fuel-air mixture injected into the engine, allowing for faster formation of the air-fuel mixture, improving combustion completeness, increasing output power, reducing fuel consumption, and enabling the engine to warm up quickly. This is especially effective for cold starts and when the ambient temperature is low, as it can shorten the start-up time.

[0072] 2) When the engine running time is greater than the preset running time and the engine speed is greater than zero, the control unit recognizes that the engine is currently in a stable starting stage. Then, the control unit adjusts and sets the optimal engine parameters according to the current stable starting stage of the engine and the oil temperature collected by the oil temperature sensor at this time.

[0073] Specifically, the control unit calculates the real-time injection advance angle during the stable starting phase based on the preset injection advance angle interpolation table 1 with respect to oil temperature. The control unit also calculates the real-time injection pulse width during the stable starting phase based on the preset injection pulse width interpolation table 2 with respect to oil temperature. The control unit sets the ignition advance angle according to the engine calibration data table, while maintaining the throttle position angle at a preset fixed value. These optimal engine parameters processed by the control unit are sent to the engine to ensure it operates according to the set parameters during the stable starting phase, guaranteeing maximum output power and minimum fuel consumption, improving starting success rate, and shortening engine start time. Simultaneously, the control unit processes the engine's oil temperature and engine speed information to obtain a heating command. Specifically, during the stable starting phase, the control unit issues a heating command to maintain heating. This command is sent to the heating control module, which drives the heating device to maintain engine heating, ensuring improved combustion completeness, increasing output power, reducing fuel consumption, improving engine start efficiency, and shortening start time.

[0074] 3) When the running time is greater than the preset running time and the engine speed fluctuation is less than the speed fluctuation tolerance value, the control unit recognizes that the engine is currently in the warm-up stage and controls the drive motor to disengage from the engine, and the engine starts successfully and reaches a stable idling speed.

[0075] Specifically, the control unit calculates and adds a weighted compensation value 1 based on a preset interpolation table 1 of the injection advance angle with respect to oil temperature to obtain the real-time injection advance angle during the stable start-up phase. The control unit also calculates and adds a weighted compensation value 2 based on a preset interpolation table 2 of the injection pulse width with respect to oil temperature to obtain the real-time injection pulse width during the stable start-up phase. The control unit sets the ignition advance angle according to the engine calibration data table, and adjusts the throttle position angle to the target idle speed position. The control unit sends the above optimal engine parameters to the engine so that the engine operates according to the set engine parameters during the warm-up phase. The injection advance angle and injection pulse width are adjusted in real-time according to the oil temperature, and further weighted compensation values ​​are added during the warm-up phase for further optimization. The system performs precise adjustments to ensure maximum output power and minimum fuel consumption. Simultaneously, the control unit processes engine oil temperature and RPM information to obtain heating commands. Specifically, during the warm-up phase, when the engine oil temperature exceeds a preset oil temperature value and the engine RPM exceeds a preset RPM value, the control unit issues a heating command to stop heating. This command is sent to the heating control module, which then drives the heating device to shut down, stopping the heating of the engine. At this point, the engine has reached a stable state, and the heat generated during its operation is sufficient to maintain efficient and stable engine operation. Therefore, shutting down the heating device will not affect engine operation and can extend the lifespan and durability of the heating device.

[0076] After identifying the engine's operating stage, the control unit combines this information with engine oil temperature and RPM data to obtain optimal engine parameters for each stage. These parameters are then sent to the engine to ensure optimal operation, improving start-up success rate, increasing output power, and reducing fuel consumption. Furthermore, the control unit generates heating commands for each operating stage, enabling the heating device to open and close according to these commands. This allows for rapid engine warm-up, shortens start-up time, and increases start-up success rate, making in-flight restart of UAV heavy-fuel engines possible. After successful engine start-up, the heating device is automatically shut off to reduce energy consumption and extend its lifespan.

[0077] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be considered as limitations on the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. For those skilled in the art, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An engine starting control method, characterized in that, include: The engine's oil temperature and speed information are obtained, the engine's operating stage is identified, the engine's operating time is obtained, and the engine's operating stage is identified based on the engine's operating time and speed information. Based on the engine's operating stage and information on engine oil temperature and speed, the engine parameters are adjusted in stages and the engine is heated in stages to start the engine. The engine's operating phases include the towing phase, the stable start-up phase, and the warm-up phase; When the drive motor starts to drive the engine and the running time is less than or equal to the preset running time, the engine is identified as being in the driving phase. When the running time is greater than the preset running time and the engine speed is greater than zero, the engine is identified as being in a stable starting phase. When the running time is greater than the preset running time and the engine speed fluctuation is less than the speed fluctuation tolerance value, the engine is identified as being in the warm-up stage. The engine parameters include injection advance angle, ignition advance angle, injection pulse width, and throttle position angle; When the engine is in the dragging phase, the injection advance angle is calculated according to the preset injection advance angle interpolation table one with respect to oil temperature, the injection pulse width is calculated according to the preset injection pulse width interpolation table two with respect to oil temperature, the ignition advance angle is set to a calibrated fixed value, and the throttle position angle is set to a preset fixed value. When the engine is in a stable starting phase, the injection advance angle is calculated according to the preset injection advance angle interpolation table with respect to oil temperature, the injection pulse width is calculated according to the preset injection pulse width interpolation table with respect to oil temperature, the ignition advance angle is adjusted according to the engine calibration data table, and the throttle position angle is maintained at a preset fixed value. When the engine is in the warm-up stage, the injection advance angle is calculated and weighted according to the preset injection advance angle interpolation table 1 with respect to oil temperature and adjusted by a weighted compensation value 1. The injection pulse width is calculated and weighted according to the preset injection pulse width interpolation table 2 with respect to oil temperature and adjusted by a weighted compensation value 2. The ignition advance angle is adjusted according to the engine calibration data table. The throttle position angle is adjusted to the idle speed target position.

2. The engine start control method according to claim 1, characterized in that, When the engine is in the dragging stage, engine heating begins when the engine oil temperature is lower than the preset oil temperature value or the engine speed is lower than the preset speed value. Maintain engine heating while the engine is in a stable starting phase; When the engine is in the warm-up phase, the engine heating will stop when the engine oil temperature is higher than the preset oil temperature value and the engine speed is higher than the preset speed value.

3. The engine start control method according to claim 1, characterized in that, The engine heating includes heating the engine combustion chamber and preheating the fuel and air injected into the engine.

4. An engine starting control system, characterized in that, include: A heating device is installed on the engine; The data acquisition unit collects engine oil temperature and speed information; The control unit receives engine oil temperature and speed information, identifies the engine's operating stage, obtains the engine's operating time, identifies the engine's operating stage based on the engine's operating time and speed information, processes the engine parameters and heating commands based on the engine's operating stage and engine oil temperature and speed information, controls the heating device to work through the heating commands, and sends the engine parameters to the engine to control engine start. The engine's operating phases include the towing phase, the stable start-up phase, and the warm-up phase; When the drive motor starts to drive the engine and the running time is less than or equal to the preset running time, the engine is identified as being in the driving phase. When the running time is greater than the preset running time and the engine speed is greater than zero, the engine is identified as being in a stable starting phase. When the running time is greater than the preset running time and the engine speed fluctuation is less than the speed fluctuation tolerance value, the engine is identified as being in the warm-up stage. The engine parameters include injection advance angle, ignition advance angle, injection pulse width, and throttle position angle; When the engine is in the dragging phase, the injection advance angle is calculated according to the preset injection advance angle interpolation table one with respect to oil temperature, the injection pulse width is calculated according to the preset injection pulse width interpolation table two with respect to oil temperature, the ignition advance angle is set to a calibrated fixed value, and the throttle position angle is set to a preset fixed value. When the engine is in a stable starting phase, the injection advance angle is calculated according to the preset injection advance angle interpolation table with respect to oil temperature, the injection pulse width is calculated according to the preset injection pulse width interpolation table with respect to oil temperature, the ignition advance angle is adjusted according to the engine calibration data table, and the throttle position angle is maintained at a preset fixed value. When the engine is in the warm-up stage, the injection advance angle is calculated and weighted according to the preset injection advance angle interpolation table 1 with respect to oil temperature and adjusted by a weighted compensation value 1. The injection pulse width is calculated and weighted according to the preset injection pulse width interpolation table 2 with respect to oil temperature and adjusted by a weighted compensation value 2. The ignition advance angle is adjusted according to the engine calibration data table. The throttle position angle is adjusted to the idle speed target position.

5. The engine start control system according to claim 4, characterized in that, The acquisition unit includes an oil temperature sensor and a crankshaft position sensor. The oil temperature sensor is installed in the crankcase to collect the oil temperature, and the crankshaft position sensor collects the crankshaft speed to obtain the engine speed.

6. The engine start control system according to claim 4, characterized in that, The control unit sends a heating command to the heating control module, which drives the heating device to work. The heating control module has at least two parallel connections between the control unit and the heating device.

7. The engine start control system according to claim 4, characterized in that, It also includes a host computer connected to the control unit, which displays the engine's operating stage, engine parameters, and heating status.

8. The engine start control system according to claim 4, characterized in that, The heating device is installed in the engine's air intake.

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