One-key rotating speed increasing and idling control method based on torque control

Abstract

The invention relates to the field of vehicle control methods, in particular to a torque control-based one-key rotating speed increasing and idle speed control method, which comprises the following steps of: judging whether a vehicle meets a PTO (Power Take Off) starting control condition or not; performing PTO target rotating speed control of the engine according to whether the PTO is started or not; pTO rotating speed closed-loop control is carried out, and after the PTO is started, the maximum value of the PTO target rotating speed and the idling target rotating speed serves as the target idling speed of the engine for control; pTO torque control is carried out, a static torque value and a dynamic torque value are obtained, and when the request signal is started, the torque of the refrigeration compressor is the combined action of the static torque and the dynamic torque and is kept according to the keeping time; and the PTO starts idling torque control, in the PTO activation state, the idling torque is kept near 0, the idling torque learning value is kept within + / -2%, and meanwhile coordinated control is conducted in cooperation with the ignition angle and the fuel injection quantity. Stable operation of the engine can be maintained, oil consumption is reduced, driving safety risks caused by flameout of the vehicle are prevented, and more comfortable driving experience is achieved.

Description

Technical Field

[0001] This invention relates to the field of vehicle control methods, specifically to a one-button speed boost and idle speed control method based on torque control. Background Technology

[0002] Most refrigerated trucks use external air conditioning compressors for air conditioning. The power required for air conditioning comes from the generator on the refrigerated truck's engine. Therefore, a large amount of current is needed to supply the air conditioning compressor in the refrigerated compartment. As a result, the engine cannot maintain this current demand at its normal idle speed. Therefore, the vehicle will experience problems such as battery depletion, unstable engine idling, or even stalling during operation.

[0003] Currently, the issue of battery depletion in refrigerated trucks is addressed through battery testing and replacement, and troubleshooting the charging system. Engine idling instability / stalling issues are handled through carbon deposit cleaning, ignition system checks, fuel supply system maintenance, and environmental adaptation adjustments. However, current solutions are all reactive, failing to address the root causes and extend the continuous service life of refrigerated trucks. Summary of the Invention

[0004] The present invention aims to provide a one-button speed increase and idle speed control method based on torque control to solve the problems of battery depletion or unstable engine idling or even engine stalling.

[0005] This solution includes a one-button speed boost and idle speed control method based on torque control, comprising the following steps: Step 1: Determine whether the vehicle meets the PTO activation control conditions; Step 2, PTO target speed adjustment, the engine PTO target speed is controlled according to whether PTO is activated; Step 3, PTO speed closed-loop control: After PTO is activated, the maximum value of the PTO target speed and the idle target speed is used as the engine target idle speed for control. Step 4, PTO torque control, obtain static torque value and dynamic torque value. When the request signal is activated, the torque of the refrigeration compressor is the combined action of static torque and dynamic torque and is maintained according to the holding time. The holding time includes the holding time of the refrigeration compressor requesting torque in the up position and the holding time of the refrigeration compressor requesting torque in the off position. Step 5: PTO is activated to control idle torque. In the PTO activated state, the idle torque is kept near 0 and the idle torque learning value is kept within ±2%. At the same time, the fuel injection quantity is coordinated with the ignition timing.

[0006] The beneficial effects of this plan are: This solution introduces one-button power rev-boost (PTO) control, along with torque control and idle stability control for refrigerated trucks, to ensure greater engine current output and improved idle stability. The method involves adding an idle speed boost switch, increasing torque compensation for refrigerated trucks, and optimizing the maximum and minimum idle torque values ​​to achieve a stable and controllable idle range. This maintains stable engine operation, reduces fuel consumption, and prevents driving safety risks associated with vehicle stalling, resulting in a more comfortable driving experience.

[0007] Furthermore, in step 1, the PTO activation control condition is: (1) PTO calibration enable bit set; (2) Throttle position is normal; (3) Throttle control is normal; (4) The PTO switch is fault-free; (5) The engine has a rotational speed; (6) Vehicle speed is below the threshold; (7) The PTO function is enabled after all conditions (1)-(6) are met.

[0008] The beneficial effect is that setting the PTO start control conditions can ensure the effectiveness of the subsequent control process.

[0009] Furthermore, in step 2, when PTO is off, the engine's PTO target speed is 0; When PTO is enabled, the PTO target speed is obtained by adding the target speed without PTO enabled to the target speed increase. After PTO is activated, the target PTO speed is obtained by filtering the speed and increasing it at fixed intervals.

[0010] The beneficial effect is that the PTO speed control allows the refrigerated truck to run more continuously and stably.

[0011] Furthermore, in step 3, the PTO speed closed-loop control and the idle speed closed-loop control are shared.

[0012] The beneficial effect is that by sharing the two controls, the resource utilization of the engine control system is optimized.

[0013] Furthermore, in step 4, the static torque value of the refrigeration compressor of the refrigeration truck under the corresponding operating conditions is obtained based on the real-time engine speed and water temperature and used as the static torque value for control. The dynamic torque value is obtained based on the current speed, and the dynamic torque and static torque are corrected by atmospheric pressure. The correction coefficient is obtained by atmospheric pressure.

[0014] The beneficial effects are: by controlling and correcting static and dynamic torque based on the actual engine operation during driving, the accuracy of engine torque control during refrigerated truck operation is improved, making the refrigerated truck operation more stable.

[0015] Furthermore, in step 4, after the holding time ends, the torque attenuation stage is attenuated by the dynamic torque filtering coefficient of the refrigeration compressor according to the on and off states, so that the torque of the refrigeration compressor gradually transitions to the static torque.

[0016] The beneficial effects are: the torque change process is slow and uniformly reduced according to different gears, avoiding engine speed fluctuations caused by excessively rapid torque reduction, so as to maintain stable engine operation and avoid engine speed fluctuations or even stalling caused by sudden torque changes. Attached Figure Description

[0017] Figure 1 This is a flowchart of an embodiment of a one-key speed boost and idle speed control method based on torque control. Detailed Implementation

[0018] The following detailed description provides further details on specific implementation methods.

[0019] A one-button speed boost and idle speed control method based on torque control, such as Figure 1 As shown, it includes the following steps: Step 1: Determine whether the vehicle meets the PTO activation control conditions. The PTO activation control conditions are: (1) PTO enable calibration setting: PTO is allowed only when the calibration is set correctly through software settings. It is the primary condition for PTO to be enabled, similar to an electronic "key".

[0020] (2) Normal throttle position: The throttle position sensor monitors the throttle opening in real time. Only when the opening is within the normal operating range will the PTO function not be affected. For example, if the throttle is stuck in an abnormal position, it will affect the engine intake air volume and thus affect the power output. In this case, the PTO activation condition will not be met.

[0021] (3) Throttle control is normal: The engine control unit must control the throttle normally to ensure that the throttle can act accurately according to the command and ensure the stable operation of the engine before and after PTO is opened.

[0022] (4) No fault in PTO switch: This is a basic requirement at the hardware level. If the PTO switch itself is faulty, such as poor contact or internal short circuit, the ECU cannot accurately receive its signal and therefore cannot properly control the PTO function.

[0023] (5) The engine has a rotation speed: that is, the engine speed is not zero. The engine must be running to provide power output; otherwise, the PTO function is meaningless.

[0024] (6) Vehicle speed is below the threshold: generally 0. The PTO function is usually used to provide power to other equipment when the vehicle is stationary or at low speed. When the vehicle speed is above the threshold, turning on PTO may have an adverse effect on vehicle driving safety and engine operation.

[0025] (7) The PTO function is enabled after all conditions (1)-(6) are met, specifically: When the enabling conditions of (1)-(6) are met, in the PTO function off state, by acquiring the signal when the PTO on button is pressed, the engine ECU recognizes the button is valid by detecting the change in the button signal (e.g., the change in voltage), and then activates the PTO function.

[0026] Once the self-locking switch is pressed, it remains in the open position. At this time, the PTO function activation status is set to 1, indicating that PTO has been successfully activated. While the PTO function is activated, if the driver presses the PTO deactivation button, the engine ECU will recognize the button's validity and deactivate the PTO function, resetting the PTO status to 0. If any of the above PTO activation conditions are not met, the PTO function will be immediately deactivated to ensure the safe operation of the engine and vehicle.

[0027] Step 2, PTO target speed adjustment: The engine's PTO target speed is controlled based on whether PTO is engaged or not. Specifically: When PTO is off, the engine's PTO target speed is 0. Since PTO is not working, the engine does not need to output additional power to maintain its speed, and no adjustment is made. When PTO is activated, the target speed for PTO is obtained by adding the target speed increase to the target speed when PTO is not activated, in order to meet the power output requirements under different operating conditions. The target speed increase is obtained from a pre-calibrated table, which is a calibrated PTO activation speed increase, for example, 500 rpm / min. After PTO is activated, the target PTO speed is achieved through speed filtering and increased at fixed intervals. The fixed interval is determined through calibration, for example, 0.5s or 1s. The increase in speed within the fixed interval is also determined through calibration, for example, an increase of 200 revolutions per second. Speed ​​filtering removes noise interference from the speed signal, making the change in target speed smoother and more stable. Speed ​​filtering uses a low-pass filter. Engine speed filtering commonly uses low-pass filtering to suppress high-frequency noise (such as instantaneous jumps caused by electromagnetic interference). The low-pass filter transfer function (...) The core component of signal processing engineering, specifically discrete-time signals. "" indicates a "unit delay operator" (i.e., delaying the output of the signal by one time unit). Increasing the target speed at a fixed period is to avoid sudden speed changes from impacting the engine and related equipment, and to ensure the smooth operation of the entire system.

[0028] Step 3: PTO speed closed-loop control. After PTO is activated, the maximum value of the PTO target speed and the idle target speed is used as the engine target idle speed for control. The PTO speed closed-loop control and the idle speed closed-loop control are shared to optimize the resource utilization of the engine control system. Sharing the PTO speed closed-loop control and the idle speed closed-loop control means that the PID control used in the idle speed closed-loop control when PTO is activated is the same as the normal idle speed (without PTO) closed-loop control. The engine control unit adjusts parameters such as throttle opening and injection pulse width based on this engine target idle speed to make the actual engine speed as close as possible to the target speed, ensuring stable engine operation under PTO conditions.

[0029] Step 4, PTO torque control: Obtain static and dynamic torque values. When the request signal is activated, the refrigeration compressor torque is maintained by the combined action of static and dynamic torques for a specified holding time. This holding time includes the holding time of the refrigeration compressor requesting torque in gear and the holding time of the refrigeration compressor requesting torque in neutral. The holding time is determined by calibration, for example, calibrated to 2 seconds or other values. Maintaining both dynamic and static torques prevents torque decay from occurring too quickly, thus ensuring more stable speed when the PTO is activated.

[0030] The static torque value of the refrigeration compressor in the refrigerated truck is obtained by measuring the engine speed and water temperature under the corresponding operating conditions. This static torque value is used for control. The static torque value is obtained by looking up the static torque table of the refrigeration compressor based on the engine speed and water temperature. The internal mechanical resistance and thermal efficiency of the engine are different under different engine speeds and water temperatures. By consulting the pre-calibrated static torque table of the refrigeration compressor, the static torque value under the corresponding operating conditions can be quickly obtained, providing basic data for torque control.

[0031] The dynamic torque value is obtained based on the current speed. The dynamic torque mainly considers the torque demand of the engine during dynamic changes. The dynamic torque value is obtained by looking up the dynamic torque table of the refrigeration compressor from the speed.

[0032] Because atmospheric pressure affects the engine's intake air volume and combustion efficiency, which in turn affects torque output, dynamic torque and static torque are corrected using atmospheric pressure. The correction factor is obtained through atmospheric pressure calculation. The correction factor is obtained by referring to the table of atmospheric pressure correction factors for refrigeration compressor torque, so as to accurately correct static and dynamic torque.

[0033] Torque control process: When the request signal is activated, the refrigeration compressor torque is a combination of static and dynamic torque, maintained for a period of time. This maintenance time is divided into two periods: the torque maintenance time for the refrigeration compressor in gear and the torque maintenance time for the refrigeration compressor in neutral. This is to meet the torque requirements of the refrigeration compressor during startup and the initial stable operation, ensuring its normal operation. After the maintenance time ends, the torque decay phase is performed separately for gear and neutral using the dynamic torque filter coefficient of the refrigeration compressor, gradually transitioning the refrigeration compressor torque to static torque. At this point, the dynamic torque is 0 N·m, maintaining the current static torque. The dynamic torque filter coefficient of the refrigeration compressor is obtained through calibration; for example, 0.76 represents a torque of 10 N·m. Decaying with a coefficient of 0.76 results in a next torque of 7.6 N·m, and the next time it is 7.6 * 0.76, resulting in 5.776 N·m. This torque change process avoids sudden torque changes that could cause engine speed fluctuations or even stalling. When the PTO switch is closed, the refrigeration compressor is turned off. The static torque gradually decreases to 0 N·m through the torque reduction filter coefficient of the refrigeration compressor. The decrease should not be too fast. A low-pass filter is used to slow down the decrease rate to avoid the torque decreases too quickly, which would cause the engine speed to fluctuate, so as to maintain the stable operation of the engine.

[0034] Step 5: PTO is activated to control idle torque. When PTO is active, the idle torque is kept near 0, which is within ±2%. The idle torque learning value is kept within ±2%. At the same time, the ignition timing and fuel injection quantity are coordinated and controlled to reduce unnecessary power consumption of the engine when PTO is working. This also ensures the stability of the engine under idling conditions and prevents engine stalling or abnormal vibration caused by torque fluctuations.

[0035] The control method in this embodiment addresses the problems of existing refrigerated trucks, which rely primarily on engine idle speed regulation to maintain normal power generation during actual operation. These problems lead to frequent engine stalling and battery depletion after a period of operation. Furthermore, relying solely on engine speed regulation for stability control results in relatively high engine speeds and unstable torque compensation. This method addresses these issues by additionally increasing engine speed to meet the high current demands of the external air conditioning compressor, preventing battery depletion and resolving the battery depletion problem in existing external refrigerated trucks. This ensures that power generation and battery condition remain at a good level. Simultaneously, it enhances torque compensation in the refrigerated truck, optimizing the maximum and minimum idle torque values, keeping the idle torque near zero, and controlling the idle torque learning value within ±2%. By coordinating ignition timing and fuel injection quantity control, unnecessary engine power consumption is reduced, ensuring idling stability and preventing engine stalling or abnormal vibration due to torque fluctuations. During torque control, the synergistic effect of static and dynamic torque, along with reasonable holding and decay mechanisms, avoids engine speed fluctuations caused by sudden torque changes, maintaining stable engine operation and preventing driving safety risks due to unstable idling or stalling. Simultaneously, it reduces fuel consumption, providing a more comfortable driving experience. The shared PTO closed-loop control and idle closed-loop control optimize the resource utilization of the engine control system, improving system resource efficiency and resulting in more precise control. Ultimately, this achieves smooth idling, reduced stalling, and prevents battery drain, enhancing vehicle driving safety.

[0036] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A one-button speed boosting and idle speed control method based on torque control, characterized in that, Includes the following steps: Step 1: Determine whether the vehicle meets the PTO activation control conditions; Step 2, PTO target speed adjustment, the engine PTO target speed is controlled according to whether PTO is activated; Step 3, PTO speed closed-loop control: After PTO is activated, the maximum value of the PTO target speed and the idle target speed is used as the engine target idle speed for control. Step 4, PTO torque control, obtain static torque value and dynamic torque value. When the request signal is activated, the torque of the refrigeration compressor is the combined action of static torque and dynamic torque and is maintained according to the holding time. The holding time includes the holding time of the refrigeration compressor requesting torque in the up position and the holding time of the refrigeration compressor requesting torque in the off position. Step 5: PTO is activated to control idle torque. In the PTO activated state, the idle torque is kept near 0 and the idle torque learning value is kept within ±2%. At the same time, the fuel injection quantity is coordinated with the ignition timing.

2. The one-key speed increase and idle speed control method based on torque control according to claim 1, characterized in that: In step 1, the PTO activation control condition is: (1) PTO calibration enable bit set; (2) Throttle position is normal; (3) Throttle control is normal; (4) The PTO switch is fault-free; (5) The engine has a rotational speed; (6) Vehicle speed is below the threshold; (7) The PTO function is enabled after all conditions (1)-(6) are met.

3. The one-key speed increase and idle speed control method based on torque control according to claim 1, characterized in that: In step 2, when PTO is off, the target PTO speed of the engine is 0. When PTO is enabled, the PTO target speed is obtained by adding the target speed without PTO enabled to the target speed increase. After PTO is activated, the target PTO speed is obtained by filtering the speed and increasing it at fixed intervals.

4. The one-key speed increase and idle speed control method based on torque control according to claim 1, characterized in that: In step 3, the PTO speed closed-loop control and the idle speed closed-loop control are shared.

5. The one-key speed increase and idle speed control method based on torque control according to claim 1, characterized in that: In step 4, the static torque value of the refrigeration compressor of the refrigeration truck under the corresponding operating conditions is obtained based on the real-time speed and water temperature of the engine and used as the static torque value for control. The dynamic torque value is obtained based on the current speed, and the dynamic torque and static torque are corrected by atmospheric pressure. The correction coefficient is obtained by atmospheric pressure.

6. The one-key speed boost and idle speed control method based on torque control according to claim 5, characterized in that: In step 4, after the holding time ends, the torque decay stage is attenuated by the dynamic torque filtering coefficient of the refrigeration compressor according to the on and off states, so that the torque of the refrigeration compressor gradually transitions to the static torque.

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