A control method for adaptive engine stall delay for a construction machine

Abstract

The application discloses a kind of control methods of engineering machinery engine self-adapting flameout delay, it is related to engine automatic control technical field, it includes when detecting flameout signal, obtains turbine actual speed and turbine side temperature;According to turbine side temperature, engine flameout is divided into multiple engineering grades;Set the basic delay time of each engineering grade, and it is dynamically corrected according to turbine actual speed to obtain actual delay flameout time;According to actual delay flameout time, delay, and in the process of delay, according to the real-time turbine actual speed and turbine side temperature, delay dynamic adjustment is carried out until the end of delay.The application is classified according to temperature as core, speed as dynamic correction basis, combined with special condition adaptation, finally realizes the accurate control of engine flameout delay time.

Description

Technical Field

[0001] This invention relates to a control method for adaptive shutdown delay of an engineering machinery engine, belonging to the field of engine automatic control technology. Background Technology

[0002] Most diesel engines in construction machinery are currently equipped with turbochargers. When the engine is running, some engine oil is used to lubricate and cool the turbocharger rotor bearings. When the engine is immediately shut off, oil lubrication is interrupted, and the turbocharger rotor continues to rotate at high speed due to inertia. The heat inside the turbocharger cannot dissipate in time, causing the turbocharger shaft and bushing to seize, damaging the bearings and shaft. Simultaneously, the undissipated heat will turn the oil remaining inside the turbocharger into carbon deposits, clogging the oil inlet and causing insufficient lubrication of the bushings, accelerating wear between the turbine shaft and bushings. Furthermore, after the engine is shut off, the fan and water pump also stop working, and the engine compartment has poor heat dissipation conditions. The turbocharger forms a high-temperature heat source within its concave cavity, which can ignite oil residue splashed onto the engine block under high temperatures through heat conduction and radiation.

[0003] After an excavator has been running under heavy load for an extended period, it is recommended to idle for 3-5 minutes before shutting it off to extend the life of the turbocharger. Currently, most excavators use an additional engine shutdown delay controller to achieve delayed engine shutdown, which is costly and cannot determine whether a shutdown delay is needed based on the actual operating conditions of the engine. The duration of the shutdown delay needs to be manually set, which places high demands on the operator.

[0004] In existing technologies, engine shutdown delay control strategies typically rely solely on a single parameter—engine speed—and employ fixed delays or delays subjectively set by the operator. This method has significant shortcomings: First, relying solely on engine speed cannot fully reflect the engine's actual operating state, resulting in limited control accuracy. Second, the fixed or manually set shutdown delay time fails to correlate with the actual operating state of the engine and turbocharger, leading to inaccurate control timing. Furthermore, even if the system provides options for immediate shutdown or a configurable delayed shutdown, its effectiveness still heavily depends on the user's experience and operational compliance. For example, if the user chooses to immediately shut down the engine after prolonged high-load operation, it may affect the turbocharger's lifespan; conversely, in scenarios where the engine can be shut down after a short period of idling, setting a long shutdown delay can lead to unnecessary energy waste. Therefore, existing technologies for engine shutdown delay control suffer from insufficient control accuracy and poor energy economy.

[0005] Construction machinery often operates continuously in open-air, dusty, high-temperature, and high-vibration environments. Turbochargers operate at temperatures ranging from 300 to 850°C for extended periods, accompanied by intense vibrations. Ordinary sensors quickly drift, fail, or detach from solder joints, making maintenance extremely difficult. Strong interference from engine ignition, fuel injection, and electric motors can easily lead to signal distortion, pulse loss, and speed fluctuations. High-temperature and vibration-resistant turbine speed and temperature sensors are expensive and do not meet the low-cost, high-reliability requirements of construction machinery. Impeller speeds can reach over 200,000 revolutions per minute, and high-frequency vibrations can easily cause sensor loosening and wiring fatigue. Turbochargers have limited space, and sensor installation is constrained by space and structure. Therefore, most construction machinery does not directly install temperature and speed sensors on the turbochargers. Furthermore, indirectly estimating turbine-side temperature based on the temperature sensor in the compressor outlet side of the boost air pipe has certain limitations: it is greatly affected by ambient temperature, intake air humidity, and altitude; the same post-compressor temperature corresponds to different turbine temperatures in different environments; transient operating conditions have large deviations, with thermal hysteresis during rapid loading and unloading, causing compressor temperature changes to lag behind turbine temperature changes. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a control method for adaptive engine shutdown delay of engineering machinery. The method calculates the turbine speed based on the actual absolute pressure, actual absolute temperature, actual air mass flow rate, actual absolute pressure at the compressor inlet, and compressor characteristic diagram of the turbocharger collected by the engine ECM. The turbine temperature is calculated based on the exhaust manifold temperature. Temperature is used as the core classification basis and speed is used as the dynamic correction basis. Combined with special working condition adaptation, the method finally achieves precise control of engine shutdown delay time.

[0007] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0008] This invention provides a control method for adaptive shutdown delay of an engineering machinery engine, comprising:

[0009] When a shutdown signal is detected, the actual turbine speed and turbine-side temperature are obtained;

[0010] Engine shutdown is classified into several operating condition levels based on turbine side temperature.

[0011] Set the base delay time for each engineering level, and dynamically adjust it according to the actual turbine speed to obtain the actual delay shutdown time.

[0012] Furthermore, the method for obtaining the actual turbine speed includes:

[0013] Real-time acquisition of the compressor's inlet actual absolute pressure, inlet actual absolute temperature, outlet actual absolute pressure, and actual air mass flow rate;

[0014] The actual turbine speed is calculated based on the actual absolute pressure at the compressor inlet, the actual absolute temperature at the inlet, the actual absolute pressure at the outlet, and the actual air mass flow rate.

[0015] Furthermore, the calculation of the actual turbine speed based on the compressor's actual inlet absolute pressure, actual inlet absolute temperature, actual outlet absolute pressure, and actual air mass flow rate includes:

[0016] The compressor boost ratio is calculated based on the actual absolute pressure at the compressor inlet and outlet, and its expression is as follows:

[0017] ;

[0018] in, Indicates the compressor boost ratio. This indicates the actual absolute pressure at the compressor outlet. This indicates the actual absolute pressure at the compressor inlet;

[0019] The corrected air mass flow rate is obtained by correcting the actual air mass flow rate based on the actual absolute temperature at the compressor inlet. Its expression is:

[0020] ;

[0021] in, Indicates the corrected mass flow rate for air. This represents the actual air mass flow rate. Indicates atmospheric pressure. This indicates the actual absolute temperature at the compressor inlet. Indicates ambient temperature;

[0022] Based on the compressor boost ratio and the corrected air mass flow rate, locate the corresponding operating point on the compressor characteristic diagram to obtain the compressor corrected speed under that operating condition.

[0023] The actual turbine speed is calculated based on the compressor corrected speed under this operating condition, and its expression is as follows:

[0024] ;

[0025] in, Indicates the actual turbine speed. This indicates the compressor corrected speed under the corresponding operating condition.

[0026] Furthermore, the method for obtaining the turbine-side temperature includes:

[0027] Real-time acquisition of engine exhaust manifold temperature;

[0028] The turbine-side temperature is calculated based on the engine exhaust manifold temperature, and its expression is:

[0029] ;

[0030] in, Indicates turbine-side temperature. Indicates the engine exhaust manifold temperature. This represents the temperature correction factor.

[0031] Furthermore, the engine shutdown is categorized into multiple operating condition levels based on turbine-side temperature, including:

[0032] To determine whether the turbine-side temperature and actual turbine speed are within safe thresholds, the turbine-side temperature and actual turbine speed are both within safe temperature thresholds. Safe speed threshold If the engine is inside the range, it is determined that it can be shut off directly without delay;

[0033] when If so, the corresponding operating condition is determined to be a low-load operating condition;

[0034] when If so, the corresponding operating condition is determined to be a medium load condition;

[0035] when If so, the corresponding working condition is determined to be a high-load working condition;

[0036] when If the condition is such that the corresponding operating condition is determined to be an extreme load condition;

[0037] in, Indicates turbine-side temperature. This indicates the upper limit threshold temperature for low-load operating conditions. This indicates the upper limit temperature threshold for medium load conditions. This indicates the upper limit threshold temperature for high-load operating conditions.

[0038] Furthermore, the safe temperature threshold The value range is 250~350℃, and the safe speed threshold is... The value range is 30,000~50,000 rpm, and the upper limit temperature threshold for the low load condition is... The value range is 550~650℃, and the corresponding basic delay time is 20~40s;

[0039] The upper temperature threshold for medium load conditions The value range is 650~750℃, and the corresponding basic delay time is 70~110s;

[0040] The upper temperature threshold for high-load operating conditions The value range is 800~900℃, and the corresponding basic delay time is 120~180s;

[0041] The basic delay time corresponding to the extreme load condition is 250~350s.

[0042] Furthermore, before classifying engine shutdown into multiple operating condition levels based on turbine side temperature, the method also includes using the base delay time corresponding to the extreme load condition as the actual delayed shutdown time when turbine side temperature acquisition is abnormal.

[0043] Furthermore, the step of dynamically correcting the actual turbine speed to obtain the actual delayed shutdown time includes:

[0044] When the actual turbine speed exceeds the upper temperature limit threshold for the corresponding operating condition, for every additional step beyond that threshold... The actual engine shutdown delay time is the base delay time plus an additional time. ;

[0045] When the actual turbine speed is lower than the lower limit threshold of the corresponding operating condition, the actual turbine speed is lower than the lower limit threshold. The actual engine shutdown delay time is the base delay time reduced by [the amount of time needed]. .

[0046] Furthermore, the aforementioned The value range is 15000~25000 rpm. The value range is 20~40s, the The value range is 15~25s; the value range of the actual delay shutdown time is 20~350s;

[0047] The upper limit threshold value for the speed under low load conditions is 80,000 to 100,000 rpm, the upper limit threshold value for the speed under medium load conditions is 140,000 to 160,000 rpm, and the upper limit threshold value for the speed under high load conditions is 170,000 to 190,000 rpm.

[0048] Furthermore, the dynamic adjustment of the delay based on the actual turbine speed and turbine-side temperature during the delay process until the delay ends includes:

[0049] S1. During the delay process, obtain the real-time actual turbine speed and turbine side temperature;

[0050] S2. Determine whether the real-time turbine speed and turbine side temperature are within the safety threshold. If both are within the safety threshold, terminate the delay and shut down the engine immediately; otherwise, continue the delay.

[0051] S3. After the actual delayed shutdown time ends, determine whether the real-time turbine speed and turbine side temperature are within the safe threshold. If they are still outside the safe threshold, the actual delayed shutdown time is increased by 30 seconds and the delay continues.

[0052] S4. Repeat S3 until the real-time turbine speed and turbine side temperature are both within the safety threshold or the actual delayed shutdown time is extended twice. If the real-time turbine speed and turbine side temperature are both within the safety threshold, the delay is terminated and the turbine is shut down immediately. If the actual delayed shutdown time is extended twice, the turbine protection alarm is triggered.

[0053] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0054] This invention can realize intelligent engine shutdown delay of excavators according to the actual working conditions of the engine, and achieve precise control of the delay time. It avoids the energy waste caused by too long a fixed delay, and also avoids the problem of the turbine not being protected if the delay is too short. At the same time, it reduces the operation requirements of the driver.

[0055] This invention solves the technical pain points of poor universality and insufficient accuracy of existing judgment logic without increasing costs. It has higher practicality and adaptability, and can effectively reduce the wear rate of turbochargers and extend the service life of turbochargers. Attached Figure Description

[0056] Figure 1 This is a flowchart illustrating a control method for adaptive engine shutdown delay in engineering machinery according to one embodiment of the present invention.

[0057] Figure 2 This is a schematic diagram illustrating the method for obtaining the actual turbine speed in the adaptive shutdown delay control method for an engineering machinery engine, as described in one embodiment of the present invention. Detailed Implementation

[0058] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0059] like Figure 1 As shown, this embodiment of the invention provides a control method for adaptive shutdown delay of an engineering machinery engine, including the following steps:

[0060] When an engine shutdown signal is detected, in this embodiment, the engine shutdown signal can be obtained from the key switch or the one-button start / stop control module, which can characterize the system's power-on start and engine shutdown functions.

[0061] Obtain real-time turbine speed and turbine-side temperature.

[0062] Combination Figure 2The specific methods for obtaining the actual turbine speed include:

[0063] Real-time acquisition of the actual absolute pressure at the compressor inlet Imported actual absolute temperature Actual absolute pressure on exports and actual air mass flow rate ;

[0064] The compressor boost ratio is calculated based on the actual absolute pressure at the compressor inlet and outlet, and its expression is as follows:

[0065] ;

[0066] in, Indicates the compressor boost ratio. This indicates the actual absolute pressure at the compressor outlet. This indicates the actual absolute pressure at the compressor inlet;

[0067] The corrected air mass flow rate is obtained by correcting the actual air mass flow rate based on the actual absolute temperature at the compressor inlet. Its expression is:

[0068] ;

[0069] in, Indicates the corrected mass flow rate for air. This represents the actual air mass flow rate. Indicates atmospheric pressure. This indicates the actual absolute temperature at the compressor inlet. Indicates ambient temperature;

[0070] Based on the compressor boost ratio and the corrected air mass flow rate, locate the corresponding operating point on the compressor characteristic diagram to obtain the compressor corrected speed under that operating condition.

[0071] The actual turbine speed is calculated based on the compressor corrected speed under this operating condition, and its expression is as follows:

[0072] ;

[0073] in, Indicates the actual turbine speed. This indicates the compressor corrected speed under the corresponding operating condition.

[0074] Methods for obtaining turbine-side temperature include: real-time acquisition of engine exhaust manifold temperature. (°C);

[0075] The turbine-side temperature is linearly positively correlated with the exhaust manifold temperature (turbine inlet exhaust gas temperature). After the exhaust gas passes through the turbine and performs work, its temperature decreases. Therefore, the turbine-side temperature can be calculated from the exhaust manifold temperature using a correction factor. The expression is as follows:

[0076] ;

[0077] in, Indicates turbine-side temperature. Indicates the engine exhaust manifold temperature. This represents the temperature correction factor, which is determined empirically based on parameters such as engine torque percentage, fuel injection quantity, and intake air volume.

[0078] The system determines whether the exhaust manifold temperature sensor signal installed on the exhaust manifold main pipe is abnormal. When the sensor fails (i.e., the turbine side temperature is abnormally acquired), the basic delay time corresponding to the extreme load condition is used as the actual delay shutdown time. The delay ends when the time expires (no subsequent steps are performed). This can protect the turbine to the maximum extent and avoid turbine damage caused by unknown parameters. The fault code can be stored in the ECU for easy traceability during subsequent maintenance.

[0079] Next, based on the turbine side temperature, the engine shutdown is divided into several operating condition levels, specifically:

[0080] To determine whether the turbine-side temperature and actual turbine speed are within safe thresholds, the turbine-side temperature and actual turbine speed are both within safe temperature thresholds. Safe speed threshold If the engine is inside the range, it is determined that it can be shut off directly without delay.

[0081] The setting of the safe temperature threshold, combined with the characteristics of the turbine bearing cavity oil and the high-temperature resistance limit of the oil seal, can effectively avoid problems such as oil coking and clogging of the oil passages, and oil seal aging and leakage. It also matches the basic high-temperature resistance requirements of the alloy turbine blades, being set below their ultimate high-temperature resistance value to provide a safety margin. Safe speed threshold. Setting the temperature threshold based on the turbine journal lubrication limits and inertial decay characteristics can prevent accelerated bearing wear caused by excessively high speeds. The value range is 250~350℃, and the safe speed threshold is... The value range is 30,000~50,000 rpm. In this embodiment, the safe temperature threshold is 350℃, and the safe speed threshold is... Get 30000 rpm.

[0082] when When the turbine load is low, the exhaust temperature and speed are at low levels, the turbine temperature rise is low, and the inertia is small. The temperature can drop to the safe threshold in a short time. Therefore, the upper limit of the temperature for low-load conditions is... The value range is 550~650℃, and the corresponding basic delay time is 20~40s. In this embodiment, ℃, corresponding to a base delay time of 30s.

[0083] when When the time is too short, the corresponding operating condition is determined to be a medium load condition. Under this condition, the turbocharger is continuously under medium load, and the exhaust temperature gradually accumulates. If the time delay is too short, it may cause slight coking of the engine oil; if the time delay is too long, it will cause unnecessary energy waste. Therefore, the upper limit threshold temperature for medium load operating conditions is set. The value range is 650~750℃, and the corresponding basic delay time is 70~110s. In this embodiment, ℃, corresponding to a base delay time of 90s.

[0084] when When the timeout occurs, the corresponding operating condition is determined to be a high-load condition. Under this condition, the exhaust temperature is high, and the engine speed is also in the high-load range. Extending the timeout can effectively reduce the turbine temperature, prevent blade creep and oil coking, and avoid the impact of boost pressure fluctuations on turbine components. Therefore, the upper limit threshold temperature for high-load operating conditions is set. The value range is 800~900℃, and the corresponding basic delay time is 120~180s. In this embodiment, ℃, corresponding to a base delay time of 150s.

[0085] when When the corresponding operating condition is determined to be the extreme load condition, the turbine temperature is close to or reaches the high temperature resistance limit of conventional turbine blades, and the speed is also at its peak. The longest delay can avoid serious failures such as turbine blade melting and bearing damage. Therefore, the basic delay time corresponding to the high load condition is 250~350s. In this embodiment, the basic delay time corresponding to the extreme load condition is 300s.

[0086] Then, the base delay time is dynamically corrected based on the actual turbine speed to obtain the actual delay shutdown time. This aims to overcome the limitations of simple temperature grading and, combined with speed deviation, achieve fine-grained control of the delay time. The specific correction rules are as follows:

[0087] When the actual turbine speed exceeds the upper limit threshold for the corresponding operating condition, for every additional step above the threshold... The actual engine shutdown delay time is increased by adding to the base delay time. This is because the higher the speed, the greater the turbine inertia, and the slower the heat dissipation. Increasing the delay can ensure that the turbine is sufficiently cooled and its speed reduced, thus avoiding bearing wear caused by high-speed inertia. The value range is 15000~25000rpm. The value range is 20~40s. In this embodiment, when the turbine speed is higher than the upper limit of the corresponding operating speed, for every 20,000 rpm higher, the actual delay shutdown time is increased by 30s on the basis of the basic delay time.

[0088] Among them, the upper limit threshold of speed under low load conditions The value range is 80,000~100,000 rpm, which is the upper limit threshold speed under medium load conditions. The value range is 140,000~160,000 rpm, which is the upper limit threshold speed under high load conditions. The value range is 170,000 to 190,000 rpm. In this embodiment, rpm rpm rpm.

[0089] When the actual turbine speed is lower than the lower speed limit threshold of the corresponding operating condition (i.e., the upper speed limit threshold of the previous operating condition), for every time it is lower than the threshold threshold... The actual engine shutdown delay time is the base delay time reduced by [the amount of time needed]. When the speed is below the lower limit, it means that the turbine load is low and there is less heat accumulation. Reducing the delay can avoid energy waste and does not affect the turbine protection effect. The value range is 15~25s. In this embodiment, when the actual turbine speed is lower than the lower limit threshold of the corresponding operating condition, the actual delay shutdown time is reduced by 20s based on the basic delay time for every 20,000 rpm below the threshold.

[0090] It should be noted that the lower limit of the dynamically corrected delay time is... To avoid insufficient delay for effective protection, the maximum delay is [value missing]. To avoid energy waste caused by excessive delay (the upper and lower limits here do not include subsequent extension time), in this embodiment the lower limit is 30s and the upper limit is 300s.

[0091] In some embodiments, special adaptation criteria are added for turbochargers with different configurations and under different environments to compensate for the limitations of general-purpose criteria logic, ensuring the universality and adaptability of the logic, and taking into account different vehicle models and usage environments. For example:

[0092] If the vehicle is an old mechanical turbocharger without an independent cooling cycle, the base delay time for all operating conditions is set according to the upper limit of the corresponding operating condition, and the speed correction rule remains unchanged. Such vehicles have low cooling efficiency and slow turbo heat dissipation. Setting the delay according to the upper limit of the operating condition can ensure that the turbocharger is sufficiently cooled and avoid turbocharger damage caused by insufficient cooling.

[0093] If the ambient temperature is ≥40℃ (such as high-temperature environments like tunnels and deserts), the base delay time for all operating conditions will be increased by 30 seconds, while the speed correction rule will remain unchanged. High-temperature environments will reduce turbine cooling efficiency, and increasing the delay can offset the effect of ambient temperature on turbine cooling, thus avoiding component damage caused by excessive turbine temperature in high-temperature environments.

[0094] In this embodiment, after the delay timer is started, the turbine side temperature and the actual turbine speed are continuously calculated in real time. A safety threshold is determined every 100ms. Once the turbine side temperature and the actual turbine speed both reach within the safety threshold, the delay is terminated in advance and the engine is immediately shut down.

[0095] If, after the base delay time, the turbine side temperature and the actual turbine speed fail to reach the safety threshold, the actual delay shutdown time is increased by 30 seconds. The above operation is repeated until both the turbine side temperature and the actual turbine speed reach within the safety threshold or the actual delay shutdown time is increased twice.

[0096] If both the turbine-side temperature and the actual turbine speed are within the safe threshold, the delay is terminated and the engine is immediately shut down. If, after two additional delays in the shutdown time, the turbine-side temperature and the actual turbine speed are still outside the safe threshold, a turbine protection alarm is triggered, forcibly restricting the internal combustion engine from starting to prevent turbine damage. Forcibly restricting starting further mitigates severe turbine damage in extreme situations, while the fault alarm signal facilitates fault tracing and repair.

[0097] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A control method for adaptive shutdown delay of an engineering machinery engine, characterized in that, include: When a shutdown signal is detected, the actual turbine speed and turbine-side temperature are obtained; Engine shutdown is classified into several operating condition levels based on turbine side temperature. Set the base delay time for each engineering level, and dynamically adjust it according to the actual turbine speed to obtain the actual delay shutdown time; The delay is based on the actual engine shutdown time, and the delay is dynamically adjusted according to the real-time actual turbine speed and turbine side temperature during the delay until the delay ends.

2. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 1, characterized in that, The method for obtaining the actual turbine speed includes: Real-time acquisition of the compressor's inlet actual absolute pressure, inlet actual absolute temperature, outlet actual absolute pressure, and actual air mass flow rate; The actual turbine speed is calculated based on the actual absolute pressure at the compressor inlet, the actual absolute temperature at the inlet, the actual absolute pressure at the outlet, and the actual air mass flow rate.

3. The control method for adaptive shutdown delay of engineering machinery engine according to claim 2, characterized in that, The calculation of the actual turbine speed based on the compressor's inlet absolute pressure, inlet absolute temperature, outlet absolute pressure, and actual air mass flow rate includes: The compressor boost ratio is calculated based on the actual absolute pressure at the compressor inlet and outlet, and its expression is as follows: ； in, Indicates the compressor boost ratio. This indicates the actual absolute pressure at the compressor outlet. This indicates the actual absolute pressure at the compressor inlet; The corrected air mass flow rate is obtained by correcting the actual air mass flow rate based on the actual absolute temperature at the compressor inlet. Its expression is: ； in, Indicates the corrected mass flow rate for air. This represents the actual air mass flow rate. Indicates atmospheric pressure. This indicates the actual absolute temperature at the compressor inlet. Indicates ambient temperature; Based on the compressor boost ratio and the corrected air mass flow rate, locate the corresponding operating point on the compressor characteristic diagram to obtain the compressor corrected speed under that operating condition. The actual turbine speed is calculated based on the compressor corrected speed under this operating condition, and its expression is as follows: ； in, Indicates the actual turbine speed. This indicates the compressor corrected speed under the corresponding operating condition.

4. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 1, characterized in that, The method for obtaining the turbine-side temperature includes: Real-time acquisition of engine exhaust manifold temperature; The turbine-side temperature is calculated based on the engine exhaust manifold temperature, and its expression is: ； in, Indicates turbine-side temperature. Indicates the engine exhaust manifold temperature. This represents the temperature correction factor.

5. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 1, characterized in that, The engine shutdown is categorized into multiple operating condition levels based on turbine-side temperature, including: To determine whether the turbine-side temperature and actual turbine speed are within safe thresholds, the turbine-side temperature and actual turbine speed are both within safe temperature thresholds. Safe speed threshold If the engine is inside the range, it is determined that it can be shut off directly without delay; when If so, the corresponding operating condition is determined to be a low-load operating condition; when If so, the corresponding operating condition is determined to be a medium load condition; when If so, the corresponding working condition is determined to be a high-load working condition; when If the condition is such that the corresponding operating condition is determined to be an extreme load condition; in, Indicates turbine-side temperature. This indicates the upper limit threshold temperature for low-load operating conditions. This indicates the upper limit temperature threshold for medium load conditions. This indicates the upper limit threshold temperature for high-load operating conditions.

6. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 5, characterized in that, The safe temperature threshold The value range is 250~350℃, and the safe speed threshold is... The value range is 30000~50000rpm; The upper temperature threshold for low-load operating conditions The value range is 550~650℃, and the corresponding basic delay time is 20~40s; The upper temperature threshold for medium load conditions The value range is 650~750℃, and the corresponding basic delay time is 70~110s; The upper temperature threshold for high-load operating conditions The value range is 800~900℃, and the corresponding basic delay time is 120~180s; The basic delay time corresponding to the extreme load condition is 250~350s.

7. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 1, characterized in that, Before classifying engine shutdown into multiple operating condition levels based on turbine side temperature, the method also includes using the base delay time corresponding to the extreme load condition as the actual delayed shutdown time when turbine side temperature acquisition is abnormal.

8. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 5, characterized in that, The process of dynamically correcting the actual turbine speed to obtain the actual delayed shutdown time includes: When the actual turbine speed exceeds the upper limit threshold for the corresponding operating condition, for every additional step beyond that threshold, the actual turbine speed... The actual engine shutdown delay time is the base delay time plus an additional time. ; When the actual turbine speed is lower than the lower limit threshold of the corresponding operating condition, the actual turbine speed is lower than the threshold value. The actual engine shutdown delay time is the base delay time reduced by [the amount of time needed]. .

9. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 8, characterized in that, The The value range is 15000~25000 rpm. The value range is 20~40s, the The value range is 15~25s; the value range of the actual delay shutdown time is 20~350s; The upper limit threshold value for the speed under low load conditions is 80,000 to 100,000 rpm, the upper limit threshold value for the speed under medium load conditions is 140,000 to 160,000 rpm, and the upper limit threshold value for the speed under high load conditions is 170,000 to 190,000 rpm.

10. The control method for adaptive shutdown delay of an engineering machinery engine according to claim 1, characterized in that, The process of dynamically adjusting the delay based on the actual turbine speed and turbine-side temperature until the delay ends includes: S1. During the delay process, obtain the real-time actual turbine speed and turbine side temperature; S2. Determine whether the real-time turbine speed and turbine side temperature are within the safety threshold. If both are within the safety threshold, terminate the delay and shut down the engine immediately; otherwise, continue the delay. S3. After the actual delayed shutdown time ends, determine whether the real-time turbine speed and turbine side temperature are within the safe threshold. If they are still outside the safe threshold, the actual delayed shutdown time is increased by 30 seconds and the delay continues. S4. Repeat S3 until the real-time turbine speed and turbine side temperature are both within the safety threshold or the actual delayed shutdown time is extended twice. If the real-time turbine speed and turbine side temperature are both within the safety threshold, the delay is terminated and the turbine is shut down immediately. If the actual delayed shutdown time is extended twice, the turbine protection alarm is triggered.

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