Solenoid valve control method and device and vehicle clutch control system

Abstract

The invention provides an electromagnetic valve control method and device and a vehicle clutch control system, and belongs to the technical field of vehicle clutch control. The method comprises the steps that the target position, the actual position and the target position change rate of a clutch are obtained; based on the position deviation, the actual position, the target position change rate and a preset control strategy, at least two electromagnetic valves with different hole diameters are controlled to execute a first combination action so as to drive a clutch to execute combination or separation operation; the position deviation is equal to the difference value between the actual position and the target position; when it is determined that the position of the clutch is overshoot according to the position deviation, the maximum overshoot amount in the current overshoot event is obtained; determining a second combined action according to the threshold range of the maximum overshoot; and controlling at least two electromagnetic valves with different apertures to execute a second combined action. Overshoot is effectively relieved, and the clutch control precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle clutch control, and particularly relates to a solenoid control method and device and a vehicle clutch control system. BACKGROUND

[0002] At present, the clutch of a commercial vehicle equipped with an AMT (Automated Manual Transmission) is usually driven in a pneumatic form, because the pneumatic form has a large output force, a low cost and a high reliability. The engagement and disengagement of the clutch is realized by controlling the gas filled into or discharged from a pneumatic actuator (clutch pump) of the clutch, and the process is generally controlled by high-speed on-off solenoids (such as intake valves and exhaust valves). The accurate control of the clutch position is crucial to the smoothness of vehicle starting, the stability of creep control and the quality of gear shifting.

[0003] At present, the position control of the pneumatic clutch in the industry generally adopts a strategy based on PID (Proportion-Integral-Derivative) control or its improved type (such as feedforward-PID compound control). For example, the existing strategy is to use a high duty cycle signal to drive the solenoid to achieve a fast response when the position deviation is large, and to use a low duty cycle signal for fine adjustment to reduce the steady-state error when the position deviation is small.

[0004] However, due to the inherent characteristics of the pneumatic system, such as the compressibility of gas, the transmission delay of pipeline, the nonlinearity of friction and other factors, the system has problems such as response lag and obvious speed fluctuation. The above existing control scheme has the following significant defects: the control parameters (such as PID parameters or duty cycle switching threshold) are usually fixed by pre-calibration, and lack of adaptive ability. When the system dynamic characteristics change due to individual differences (such as clutch wear, gas path length change), environmental changes (such as temperature affecting air viscosity) or different driving conditions, it is difficult for the fixed control parameters to remain optimal in all cases. In particular, when the control process occurs "overrun" phenomenon (i.e. the actual position exceeds the target position), the existing strategy cannot adjust the control strategy in real time and adaptively according to the amount of overrun, but only relies on the preset and fixed feedback adjustment mechanism for lag correction. This will cause the consistency of clutch control accuracy to decrease, and further cause problems such as vehicle starting impact and gear shifting jerk, affecting the driving smoothness and comfort of the vehicle. SUMMARY

[0005] Therefore, it is necessary to provide a solenoid control method, device and vehicle clutch control system to solve the technical problems of control accuracy decrease and poor clutch control stability caused by the inability to adaptively adjust the solenoid when the overrun occurs in the prior art.

[0006] To solve the above technical problems, in a first aspect, the present application provides an electromagnetic valve control method, comprising: obtaining a target position, an actual position, and a target position change rate of a clutch; based on a position deviation, the actual position, the target position change rate, and a preset control strategy, controlling at least two electromagnetic valves with different aperture sizes to perform a first combined action to drive the clutch to perform a combination or separation operation; the position deviation is equal to the difference between the actual position and the target position; when it is determined according to the position deviation that the position of the clutch overshoots, obtaining a maximum overshoot amount in a current overshoot event; determining a second combined action according to a threshold range in which the maximum overshoot amount is located; the second combined action is different from the first combined action, and the first combined action and the second combined action control the same type of electromagnetic valve; controlling at least two electromagnetic valves with different aperture sizes to perform the second combined action.

[0007] In a possible implementation, the preset control strategy is determined by the following method: dividing a stroke of the clutch into a plurality of continuous position intervals; presetting a corresponding combined action for each position interval, the combined action being determined by the actual position of the clutch, the position deviation, and the target position change rate.

[0008] In a possible implementation, the obtaining of the maximum overshoot amount in the current overshoot event comprises: starting from the detection of the occurrence of overshoot in any one of the position intervals, continuously monitoring the position deviation; determining the maximum absolute value of the position deviation occurring during the overshoot duration as the maximum overshoot amount.

[0009] In a possible implementation, the determining of the second combined action according to the threshold range in which the maximum overshoot amount is located comprises: determining an overshoot position interval corresponding to the actual position of the clutch when the overshoot occurs; obtaining an original combined action corresponding to the overshoot position interval according to the preset control strategy; according to the maximum overshoot amount, offsetting the serial number of the original combined action by N positions to obtain the serial number of the second combined action according to a predefined offset rule, N being a positive integer.

[0010] In a possible implementation, the offset rule is: if 0<|E_max| ≤ e1, N=1; If e1<|E_max|≤e2, N=2; If e2<|E_max|≤e3, N=3; Wherein, e1, e2, e3 are preset clutch position deviation threshold values, and e1<e2<e3, and |E_max| is an absolute value of the maximum overshoot.

[0011] In a possible implementation, the combined action is defined by a solenoid control state matrix, a row of the solenoid control state matrix corresponds to a combined action sequence number of different solenoids, and a column corresponds to a switch state of different solenoids, and the switch state includes full opening, PWM control, and closing.

[0012] In a possible implementation, when the clutch performs a combination operation, the solenoid is an exhaust solenoid; and when the clutch performs a separation operation, the solenoid is an intake solenoid.

[0013] In a possible implementation, the position overshoot of the clutch is determined according to the position deviation, including: In the clutch combination process, it is determined that the overshoot occurs when the position deviation is greater than zero; In the clutch separation process, it is determined that the overshoot occurs when the position deviation is less than zero.

[0014] In a second aspect, the present application further provides an electronic control device, comprising a memory and a processor, wherein, The memory is configured to store a program. The processor is coupled to the memory and is configured to execute the program stored in the memory to implement the steps in the solenoid control method described in any of the above implementation manners.

[0015] In a third aspect, the present application further provides a vehicle clutch control system, comprising: A pneumatically driven clutch; At least two solenoids with different aperture sizes, used to control the gas flow into or out of the clutch; The electronic control device described in the second aspect is used to control the action of the solenoid.

[0016] The beneficial effects of the present application are: the electromagnetic valve control method provided by the present application can timely and accurately capture the overshoot event and quantify the maximum overshoot by monitoring the position deviation in real time during control, and then dynamically adjusts the control strategy of the electromagnetic valve (second combined action) according to the severity of the overshoot, realizes accurate correction of the current overshoot, significantly improves the accuracy of clutch position control, effectively suppresses overshoot, overcomes the lag and nonlinearity of the pneumatic system, and makes the clutch maintain high-precision position tracking under different vehicles and different working conditions. Further, the advantages of the double electromagnetic valve (large valve + small valve) are fully utilized, the large valve ensures the large flow output of the system, so that the clutch can respond quickly when it needs to be quickly combined or separated (such as starting, rapid acceleration); and the small valve provides fine adjustment capability, after detecting the overshoot, by immediately switching to the second combined action dominated by the small valve (such as small flow back suction or inching), it can quickly "brake" to suppress overshoot, and avoid system oscillation caused by violent action of the large valve, truly achieving "fast when needed, slow when needed", achieving the best balance between dynamic response and static stability, considering response speed and system stability, realizing fast and impact-free control, automatically adjusting control parameters when the clutch control system overshoots, eliminating overshoot, improving the consistency and stability of clutch control, realizing smoother starting, more stable peristalsis, more agile and impact-free gear shifting, and improving the driving comfort and reliability of commercial vehicles. Further, the control algorithm is optimized to completely rely on the existing double electromagnetic valve hardware architecture and sensors (position sensor), without the need to add expensive pressure sensors, flow sensors or more complex mechanical structures, so that the control performance can be greatly improved, thus improving the product competitiveness without increasing additional material costs, having high cost-effectiveness, and being very suitable for large-scale industrial application. BRIEF DESCRIPTION OF DRAWINGS In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0017] Figure 1 An embodiment flowchart of the electromagnetic valve control method provided by the present application is shown in the figure. Figure 2 An embodiment flowchart of setting a preset control strategy provided by the present application is shown in the figure. Figure 3 An embodiment flowchart of the present application Figure 1 An embodiment flowchart of S300 in the present application is shown in the figure. Figure 4 An embodiment flowchart of the present application Figure 1An embodiment flowchart of the clutch S400; Figure 5 A curve change schematic diagram of overshoot occurring in the clutch combination process provided by the present application; Figure 6 A curve change schematic diagram of overshoot elimination in the clutch combination process after the adaptive adjustment of the solenoid valve combination mode provided by the present application; Figure 7 An embodiment structure schematic diagram of the electronic control device provided by the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0019] In the description of the embodiments of the present application, unless otherwise specified, the meaning of “multiple” is two or more. The association relationship of the associated objects is described by “and / or”, which means that there can be three relationships, for example: A and / or B, which can represent the three cases of A alone, A and B together, and B alone.

[0020] The “first”, “second” and the like described in the embodiments of the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the technical features limited by “first” and “second” can explicitly or implicitly include at least one of the features.

[0021] In this document, the reference to “embodiments” means that the specific features, structures or properties described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily mean that the same embodiment is referred to, nor does it mean that the independent or alternative embodiments are mutually exclusive or alternative to each other. The skilled person in the art explicitly and implicitly understands that the embodiments described herein can be combined with other embodiments.

[0022] The present application provides a solenoid valve control method, device and vehicle clutch control system, which are described below respectively.

[0023] Figure 1 An embodiment flowchart of the solenoid valve control method provided by the present application is shown as follows, Figure 1 The solenoid valve control method comprises: S100, obtaining a target position, an actual position and a target position change rate of a clutch.

[0024] It should be noted that the vehicle clutch control system provided by the application comprises: a pneumatically driven clutch; at least two electromagnetic valves (for example, a first electromagnetic valve and a second electromagnetic valve) with different diameters for controlling the gas flow into or out of the clutch; and an ECU (Electronic Control Unit) for controlling the operation of the electromagnetic valves. The clutch has a movable actuator (such as a piston), and the position of the actuator represents the "actual position" of the clutch. Because the first electromagnetic valve and the second electromagnetic valve have different diameters, they can provide different gas flows under the same pressure difference. Generally, the electromagnetic valve with a larger diameter (which can be referred to as a "large valve") can provide a larger gas flow to achieve fast response, and the electromagnetic valve with a smaller diameter (which can be referred to as a "small valve") can provide more precise gas flow control to achieve high-precision positioning. The ECU, as the core control unit, is electrically connected with a position sensor (not shown) on the clutch and the first electromagnetic valve and the second electromagnetic valve. The ECU is configured to perform the steps corresponding to the electromagnetic valve control method shown in Figure 1 .

[0025] The ECU first receives a clutch target position instruction from an upper control algorithm (such as a transmission control unit TCU). At the same time, the ECU collects real-time actual position signals of the clutch through a position sensor (such as a displacement sensor or an angle sensor) installed on the clutch actuator 10. In addition, the ECU calculates the target position change rate (i.e., target speed) at the current time through a differential algorithm (for example, a first-order backward difference) based on the historical data of the target position instruction.

[0026] S200, based on the position deviation, the actual position, the target position change rate, and a preset control strategy, control at least two electromagnetic valves with different diameters to perform a first combined action to drive the clutch to perform a combination or separation operation; the position deviation is equal to the difference between the actual position and the target position.

[0027] It should be noted that the preset control strategy defines the optimal electromagnetic valve combination mode to be adopted under different (P, E, R) combination conditions, i.e., under different combinations of position deviation, actual position, and target position change rate. The electromagnetic valve combination mode defines the operation or state of different electromagnetic valves. After obtaining the three key parameters of target position, actual position, and target position change rate, the ECU enters the closed-loop control stage. First, the position deviation is calculated, wherein the position deviation is equal to the difference between the target position and the actual position. Then, based on the position deviation, the actual position, the target position change rate, and the preset control strategy, the corresponding driving signal is obtained to control at least two electromagnetic valves with different diameters to perform a first combined action.

[0028] S300, obtaining a maximum overshoot amount in the current overshoot event when it is determined according to the position deviation that the position of the clutch overshoots.

[0029] It should be noted that although there is a fine control mode, due to the nonlinearity of the hydraulic system, the change of oil temperature, the uncertainty of friction and other factors, the clutch may continue to move due to inertia or pressure fluctuation after the actual position reaches the target position, resulting in overshoot. In order to detect and quantify this overshoot event, the ECU continuously monitors the position deviation, and once it is determined that overshoot occurs according to the position deviation, the ECU records and tracks the maximum overshoot amount in this overshoot process.

[0030] S400, determining a second combined action according to the threshold range in which the maximum overshoot amount is located; the second combined action is different from the first combined action, and the first combined action and the second combined action control the same type of solenoid valve.

[0031] It should be noted that after obtaining the maximum overshoot amount, the ECU does not immediately end the control, but uses it as a key feedback information to optimize the subsequent control strategy. Specifically, according to the clutch performance and control system requirements, the ECU internally presets several overshoot amount threshold ranges, and for different threshold ranges, the ECU will determine a second combined action, which will be used to correct the current overshoot or prevent the same degree of overshoot in advance in the next similar working condition. Importantly, the second combined action is still achieved by controlling the same type of solenoid valve (such as the first solenoid valve and the second solenoid valve), but the specific control logic is different from the first combined action that led to the overshoot. In addition, the maximum overshoot amount can also be stored in the non-volatile memory as a learning value. The ECU can dynamically adjust the parameters of the first combined action in subsequent control according to the historical overshoot amount. For example, if the range C overshoot frequently occurs in a certain working condition, the ECU can directly reduce the opening PWM duty cycle of the large valve or exit the large valve in advance the next time the working condition is entered, thereby fundamentally reducing the occurrence of overshoot.

[0032] S500, controlling at least two solenoid valves with different hole diameters to execute the second combined action.

[0033] It should be noted that the ECU outputs corresponding control signals (such as high and low levels or PWM waves) to the drive circuits of at least two solenoid valves with different hole diameters according to the second combined action determined in step S400 to execute the second combined action, so as to correct the current overshoot and provide optimization basis for subsequent control.

[0034] In summary, firstly, by monitoring the position deviation in real time during control, the overshoot event can be captured in time and accurately, and the maximum overshoot amount can be quantified. Then, according to the severity of the overshoot amount, the control strategy of the electromagnetic valve is dynamically adjusted (the second combined action), the current overshoot is accurately corrected, the accuracy of the clutch position control is significantly improved, the overshoot is effectively suppressed, the hysteresis and nonlinearity of the pneumatic system are overcome, and the clutch can maintain high-precision position tracking under different vehicles and different working conditions. Further, the advantages of the double electromagnetic valve (large valve + small valve) are fully utilized. The large valve ensures the large flow output of the system, so that the clutch can respond quickly when it needs to be quickly combined or separated (such as starting and rapid acceleration). The small valve provides fine adjustment capability. After detecting the overshoot, the second combined action dominated by the small valve (such as small flow back suction or inching) is switched immediately, which can quickly "brake" to suppress overshoot and avoid system oscillation caused by the violent action of the large valve. It truly achieves "fast when needed, slow when needed", and achieves the best balance between dynamic response and static stability, taking into account response speed and system stability, achieving fast and impact-free control. When the clutch control system overshoots, the control parameters are automatically adjusted to eliminate overshoot, improve the consistency and stability of clutch control, achieve smoother starting, more stable peristalsis, more agile and impact-free gear shifting, and improve the driving comfort and reliability of commercial vehicles. Further, by optimizing the control algorithm, it completely relies on the existing double electromagnetic valve hardware architecture and sensors (position sensor), without the need to add expensive pressure sensors, flow sensors or more complex mechanical structures, so as to realize the leap in control performance. Therefore, it improves the product competitiveness without increasing additional material costs, has high cost-effectiveness, and is very suitable for large-scale industrial application.

[0035] In some embodiments of the present application, as shown in Figure 2 The preset control strategy is determined by the following method: S210, dividing the stroke of the clutch into a plurality of continuous position intervals; S220, presetting a corresponding combined action for each position interval, the combined action being determined by the actual position of the clutch, the position deviation and the target position change rate.

[0036] It should be noted that: the entire mechanical stroke of the clutch (for example, from 12mm of full disengagement to 0mm of full engagement) is divided into N continuous and non-overlapping position intervals. The division is usually based on a fixed distance threshold Thres1. For example, the stroke is 12mm, and Thres1 is set to 1mm, then the stroke can be divided into 12 continuous intervals: [12mm, 11mm), [11mm, 10mm), …, [1mm, 0mm]. The start and end points of each interval are the recording points P_i (i = 1 to 12). A corresponding combination action is preset for each position interval (equivalent to establishing a control mapping table), which is completed through the system's pre-calibration (bench test and real vehicle debugging). For each position interval [P_{i+1}, P_i), an optimal electromagnetic valve combination mode (i.e. combination action) is associated. The electromagnetic valve combination mode (i.e. combination action) comprehensively considers the actual position of the clutch, the position deviation and the target position change rate. After calibration, a preset control strategy is formed. In actual control, the system only needs to detect which position interval the current actual position P falls into, and then directly call the preset electromagnetic valve combination mode (i.e. combination action) for that position interval.

[0037] In this embodiment, the complex nonlinear control problem is decomposed into multiple relatively simple linear sub-problems (in each interval), and the entire action trajectory of the clutch is "optimized frame by frame" by independent optimization calibration of each interval, and the control accuracy is much higher than the traditional method of using a single or a few control strategies for the entire stroke. Further, the strategy is essentially a state (position) based feedforward control. Once the actual position of the clutch is identified to enter a certain position interval, the best combination "tailored" for that interval is immediately enabled, rather than being passively responsive after a large deviation occurs, which greatly reduces the control lag and makes the clutch action more accurate and smooth, thereby reducing the possibility of overshoot from the source.

[0038] Since overshoot can be an oscillation process, if only the first peak or a certain instantaneous value is taken, the severity of the overshoot may be underestimated, resulting in reduced clutch control accuracy. In order to solve this problem, in some embodiments of the present application, as shown in Figure 3 The maximum overshoot amount in the current overshoot event is obtained, including: S310, from any one of the position intervals, detecting the start of the occurrence of the overshoot, and continuously monitoring the position deviation; S320, determining that the maximum absolute value of the position deviation occurring during the overshoot duration is the maximum overshoot amount.

[0039] It should be noted that: the control system in the clutch engagement process (target position A is less than the actual position P), real-time calculation position deviation E=A-P. In the normal tracking stage, once the value of E is detected to reverse deviation (such as > 0 to < 0, < 0 to > 0) or zero, it is immediately determined that the overshoot event starts, and this detection is continuous, regardless of which preset position interval the clutch is in, ensuring the comprehensiveness and immediacy of the overshoot detection. Once the overshoot event is triggered, the system starts a special "overshoot monitoring period". In this period, the controller is no longer dominated by the regular control period, but by a higher frequency or priority, continuously reading and recording the value of position deviation E, until E returns to zero or the number of values reverses again (indicating the end of overshoot). The system sets a flag (such as Overshoot_Flag) and a set of cache in the memory. When the start of the overshoot is detected, the flag is set, and the subsequent E value is stored in the cache, ensuring reliable capture of transient overshoot phenomena and not missing critical data due to other tasks of the controller. In the continuous monitoring process of S310, the system records all position deviations E in the time window from the start of the overshoot to the end of the overshoot (E value reverses again or returns to zero), and the algorithm traverses all position deviations recorded during the overshoot to find the maximum value. Since the position deviation E is positive when the overshoot occurs during clutch engagement, the maximum value is the maximum overshoot E_max. Since the position deviation E is negative when the overshoot occurs during clutch disengagement, the minimum value is the maximum overshoot E_max. Using the maximum absolute value of the position deviation (|E|) to determine the maximum overshoot ensures that it is applicable to both disengagement and engagement processes, improving universality. In software implementation, a variable E_max=0 can be initialized. During the duration of the overshoot, whenever a new E value is read, it is compared with E_max: if |E_new|>E_max, then update E_max=|E_new|. At the end of the overshoot, the final E_max is the solution.

[0040] In this embodiment, the maximum overshoot is obtained by obtaining the maximum absolute value of the position deviation that occurs during the duration of the overshoot, avoiding one-sided judgment of the overshoot, ensuring that the obtained maximum overshoot can truly reflect the maximum impact of this overshoot event on the system, so that the subsequent compensation effort is sufficient to cover the worst case, thereby more effectively suppressing oscillation and improving the reliability of the correction effect. Further, using the maximum absolute value of the position deviation that occurs during the duration of the overshoot as the maximum overshoot does not depend on whether the overshoot occurs during engagement or disengagement, nor does it depend on the specific position interval. It is a unified and universal measurement method that simplifies the design of control logic, allows the same set of adaptive rules to be applied to different working stages of the clutch, and improves the reusability of the algorithm module and the robustness of the entire control system.

[0041] In some embodiments of the present application, as shown in Figure 4 Step S400 includes: S410, determining an overshoot position interval corresponding to the actual position of the clutch when the overshoot occurs; S420, querying an original combined action corresponding to the overshoot position interval according to the preset control strategy; S430, according to the maximum overshoot amount, offsetting the serial number of the original combined action by N bits according to a predefined offset rule to obtain the serial number of the second combined action, N being a positive integer.

[0042] It should be noted that when step S300 detects the occurrence of overshoot (i.e. at the moment when E>0), the system immediately latches the current actual position of the clutch, denoted as P_E (overshoot occurrence position). P_E is compared with each position interval divided in the preset control strategy. The specific method is to traverse all intervals [P_{i+1}, P_i), and find the specific interval that satisfies P_{i+1}≤P_E<P_i. This interval is the overshoot position interval. After determining the overshoot position interval, the preset control strategy is directly queried, which defines the optimal electromagnetic valve combination S_n to be adopted under the typical working condition (P_i, E_i, R_i) of each position interval i. At this time, the combination S_n1 queried according to the overshoot position interval corresponding to the actual position of the clutch when the overshoot occurs is the “original combined action” that the system was executing for this interval before the overshoot occurred. The serial number S_n1 of the original combined action is added by the offset amount N to obtain a new combined serial number S_n=S_{n1+N}, and the electromagnetic valve combination corresponding to this new combined serial number is the second combined action aimed at eliminating the overshoot. It should be noted that the total number of preset electromagnetic valve combinations is fixed (such as S1-S9), and the offset calculation needs to ensure that the new serial number is within the effective range (such as 1-9), and if it exceeds, the boundary value is taken.

[0043] In this embodiment, the corresponding original action combination is obtained by determining the over-adjustment position interval query, the second action combination aiming to eliminate the over-adjustment is obtained according to the offset rule and the original action combination, the one-size-fits-all global parameter adjustment is avoided, the subsequent correction measures can accurately act on the problem source, and the correction efficiency and the intelligent level of the controller are greatly improved. Moreover, the over-adjustment correction process is extremely simple and has extremely low calculation load, and is very suitable for a vehicle-mounted real-time control system. Further, the offset operation is switching between a group of predefined and fully verified 'effective combinations', the new combination (second combined action) and the original combination are 'adjacent' or 'close' in control characteristics (because the serial numbers are close), which means that the change of the control output is sequential and progressive, rather than random or jumping. This ordered switching avoids the dramatic change of the electromagnetic valve state, prevents the introduction of new shocks or oscillations due to the mutation of the control instruction, and ensures the stability of the adaptive adjustment process.

[0044] In some embodiments of the present application, the offset rule is: If 0<|E_max|≤e1, N=1; If e1<|E_max|≤e2, N=2; If e2<|E_max|≤e3, N=3; Wherein, e1, e2, e3 are preset clutch position deviation thresholds, and e1<e2<e3, and |E_max| is the absolute value of the maximum over-adjustment.

[0045] It should be noted that: in the development stage of the control system, three key over-adjustment thresholds: e1, e2, e3 are pre-calibrated through bench tests and real vehicle debugging. These thresholds are constant values with clear physical meaning (unit: millimeter), and satisfy e1<e2<e3. e1 (slight over-adjustment threshold) is set as the over-adjustment level that the system can tolerate, but needs to be optimized by fine tuning. It usually corresponds to the working condition that needs to be finely optimized for comfort. e2 (moderate over-adjustment threshold) is set as the over-adjustment level that indicates that the control strategy is obviously mismatched and needs to be adjusted significantly. It usually corresponds to the impact or jerk that can be obviously perceived. e3 (severe over-adjustment threshold) is set as the safety red line of system stability, and exceeding this value may mean that more extreme intervention or fault handling is needed. After each over-adjustment event is detected, the controller performs a simple conditional judgment process: reads the measured maximum over-adjustment absolute value |E_max|, sequentially compares |E_max| with the preset thresholds e1, e2, e3, and uniquely determines the value of the offset N according to the interval in which |E_max| falls.

[0046] In this embodiment, the offset rule has a hierarchical response characteristic, avoiding the rough way of using the same correction regardless of the size of the overshoot. A slight overshoot (such as 0.3mm) only needs to adjust the control combination to the conservative direction by one step (N = 1), avoiding "overcorrection"; while a serious overshoot (such as 1.0mm) needs to be adjusted by two or three steps (N = 2 or 3) to ensure that it can suppress the oscillation. This characteristic of the correction degree being proportional to the problem severity enables the system to eliminate the overshoot smoothly at the most appropriate response speed, greatly improving the control quality and efficiency. Further, the offset rule does not depend on the accurate mathematical model of the controlled object, nor does it need complex online optimization calculation. Its algorithm is extremely simple, and the computational overhead is minimal, making it very suitable for fast and reliable execution in vehicle-mounted microcontrollers (MCU) with limited computing resources. Further, the offset N is an integer, and usually takes a small value (1, 2, 3), which means that the new control combination (S_{n1+N}) and the original combination (S_{n1}) are adjacent or close in the pre-defined control strategy sequence, ensuring that the control command does not jump dramatically, but smoothly and orderly transitions to a more conservative strategy, which is crucial for avoiding secondary impact or oscillation caused by the sudden change of the solenoid state, and ensuring the stability of the adaptive adjustment process. Further, the three thresholds e1, e2, e3 have intuitive physical meaning (overshoot amount in millimeters), and engineers can directly set and adjust these parameters according to the actual performance of the vehicle (such as the smoothness requirement). For example, for a vehicle with high comfort requirements, e1 can be set smaller, making the system more sensitive to small overshoots. This design transparency greatly simplifies the matching and calibration process of the system, reducing development costs and cycles. Of course, four or five thresholds can also be set according to requirements.

[0047] In some embodiments of the present application, the combined action is defined by a solenoid control state matrix, wherein the rows correspond to different combined action numbers of the solenoids, and the columns correspond to different switch states of the solenoids, including full opening, PWM control, and closing.

[0048] Note that: solenoid control state matrix is a query table that accurately associates "control strategy" (combination action number) with "physical execution" (solenoid switch state). Each row represents a unique, pre-defined solenoid combination action, and is assigned a unique number (such as S1 to S9). These numbers correspond to different control strategies or "gears". Each column corresponds to a controlled solenoid. In the present application, at least two columns are included, representing the exhaust large valve (or intake large valve) and the exhaust small valve (or intake small valve). If the system is more complex, the number of columns can be expanded to include more solenoids. The numerical value (such as 0, 1) or symbol of each element in the solenoid control state matrix represents the switch state of the corresponding solenoid under a specific combination action. The state usually has three types, respectively, full open (usually represented by 1 or a specific code, indicating that the solenoid is fully open, providing maximum flow), PWM control (usually represented by a value between 0-1 or a specific symbol, indicating that the solenoid is switched at a specific duty ratio, providing adjustable intermediate flow), and closed (usually represented by 0, indicating that the solenoid is completely closed, with zero flow).

[0049] In this embodiment, the solenoid control state matrix pre-defines all possible and effective control outputs in a limited and discrete set, and each combination action is a functionally clear "function module", which makes the control logic no longer a fuzzy and continuous calculation result, but a clear and enumerable "strategy selection", which greatly simplifies the design and debugging process of the control system.

[0050] In some embodiments of the present application, when the clutch performs the engagement operation, the solenoid is an exhaust solenoid; when the clutch performs the disengagement operation, the solenoid is an intake solenoid.

[0051] It should be noted that: pneumatic clutch generally includes a cylinder, inside the piston, the piston side (or both sides) through the compressed air, and usually installed with return spring. In the process of engagement, the air pressure needs to overcome the spring force; in the process of separation, the gas pressure is usually released, relying on the spring force to return the piston. The clutch is pushed during the engagement process, so that the clutch friction plate is pressed tightly, and the power is transmitted. The piston is retracted during the separation process of the clutch, so that the clutch friction plate is separated and the power is interrupted. The inlet solenoid valve is a valve that controls the compressed air from the air source into the cylinder. The exhaust solenoid valve is a valve that controls the air in the cylinder to be discharged to the atmosphere. The clutch needs to be pressed during the engagement process, that is, the gas pressure in the cylinder needs to be reduced, so that the spring force pushes the piston to move and realizes the engagement, therefore, to reduce the pressure in the cylinder, the air in the cylinder needs to be discharged, and the valve that controls the air discharge is the exhaust solenoid valve, therefore, during the engagement process, the control system controls the exhaust rate by opening the exhaust solenoid valve (large valve, small valve or PWM combination thereof), thereby controlling the speed and position of the clutch engagement. When the electronic control device issues a "engagement" instruction, the control algorithm will dynamically select the combination of the exhaust solenoid valve based on the target position, the actual position and the deviation, and the inlet solenoid valve remains closed during this process, cutting off the high-pressure gas source.

[0052] The clutch needs to be separated during the separation process, that is, the gas pressure in the cylinder needs to be increased to overcome the spring force and push the piston back to realize the separation, therefore, to increase the pressure in the cylinder, compressed air needs to be filled into the cylinder, and the valve that controls the compressed air to enter is the inlet solenoid valve, therefore, during the separation process, the control system controls the air intake rate by opening the inlet solenoid valve (large valve, small valve or PWM combination thereof), thereby controlling the speed and position of the clutch separation. When the electronic control device issues a "separation" instruction, the control algorithm will dynamically select the combination of the inlet solenoid valve for control, and the exhaust solenoid valve is usually kept closed during this process to ensure that the pressure can be quickly established.

[0053] In some embodiments of the present application, the position overshoot of the clutch is determined according to the position deviation, comprising: In the process of engagement of the clutch, when the position deviation is greater than zero, it is determined that overshoot occurs; In the process of separation of the clutch, when the position deviation is less than zero, it is determined that overshoot occurs.

[0054] It should be noted that: clutch from the separation state (position value is large, for example, 12mm) to the combination state (position value is small, for example, 0mm) movement, the piston pushes the clutch plate to press, so that the actual position P quickly and smoothly track the target position A from large to small changes. In the process of combination, if the "inertia" of the actual position P causes it to be over-tightened, that is, the value of P is less than the target position A (because the smaller the position value represents the tighter the press), overshoot occurs. The judgment logic is E = A-P, when overshoot occurs, P < A, therefore, E = A-P > 0. The controller continuously monitors the deviation E during the combination process, and once E changes from negative or zero to positive, it can be immediately determined that the system has overshoot, and the overshoot amount E and the actual position P_E at this moment are recorded.

[0055] When the clutch moves from the combined state (small position value, for example, 0mm) to the separation state (large position value, for example, 12mm), the piston retreats and the clutch plate separates, so that the actual position P quickly and smoothly tracks the target position A from small to large changes. In the process of separation, if the "inertia" of the actual position P causes it to be over-separated, that is, the value of P is greater than the target position A (because the larger the position value represents the more open the press), overshoot occurs. The judgment logic is E = A-P, when overshoot occurs, P > A, therefore, E = A-P < 0. The controller continuously monitors the deviation E during the separation process, and once E changes from positive or zero to negative, it can be immediately determined that the system has overshoot. In summary, first determine whether the current is in the combination process or the separation process (can be determined by the target position trend or the command), and set the overshoot trigger condition according to the different processes, that is, set the overshoot flag to E > 0 in the combination process. Set the overshoot flag to E < 0 in the separation process. The controller performs condition judgment in each control period, and once the condition is met, the overshoot processing subroutine (such as obtaining the maximum overshoot amount, adjusting the electromagnetic valve combination, etc.) is triggered.

[0056] Among them, the basic principle of the pneumatic form driven clutch control system is: when the two different hole diameters of the inlet electromagnetic valve are opened, the clutch separates under the pressure of the gas; when the two different hole diameters of the exhaust electromagnetic valve are opened, the gas pressure gradually decreases, and the clutch is combined. Taking the clutch combination process as an example, the basic parameters of the control system include: The basic parameters of the control system include: X, the large exhaust valve of the clutch; Y, the small exhaust valve of the clutch; E, the deviation between the target position and the actual position of the clutch, E = A-P; P, the actual position of the clutch; A, the target position of the clutch; R, the rate of change of the target position of the clutch; F, the electromagnetic valve combination mode; The electromagnetic valve combination mode is as follows: ;

[0057] S, clutch solenoid valve combination; , exhaust large valve full open; , exhaust large valve PWM control; , exhaust large valve closed; , exhaust small valve full open; , exhaust small valve PWM control; , exhaust small valve closed; , solenoid valve combination mode.

[0058] is the solenoid valve control state matrix, the parameters are determined by the actual position P of the clutch, the position deviation E of the clutch and the target position change rate R of the clutch; ; ; Example: indicates that the fifth solenoid valve combination is adopted, the exhaust large valve is fully open, and the exhaust small valve is closed.

[0059] Position overshoot: during the clutch position control process, the actual position exceeds the target position, during the clutch engagement process, the actual position is less than the target position, and during the clutch disengagement process, the actual position is greater than the target position; the solenoid valve control state matrix corresponding to the actual position P of the clutch, the position deviation E of the clutch and the target position change rate R of the clutch is recorded in turn during the clutch engagement process as follows: ; ; Thres1: interval threshold; P i (i=1, 2, 3…12) are 12 position values recorded at Thres1 intervals from the fully separated position to the fully engaged position during the clutch engagement process, E i (i=1, 2, 3…12) is the position deviation corresponding to P i (i=1, 2, 3…12), R i (i=1, 2, 3…12) is the target position change rate corresponding to P i (i=1, 2, 3…12); P i (i=1, 2, 3…12) is obtained according to the clutch position sensor; E i (i=1, 2, 3…12) is obtained according to real-time calculation; R i (i=1, 2, 3…12) is obtained according to real-time calculation.

[0060] The overmodulation detection takes the clutch engagement process as an example. When the clutch has overmodulation during the engagement process, i.e. E>0, the actual position P of the clutch at the time of overmodulation is obtained E , the change rate R of the target position of the clutch E , the maximum overmodulation amount is denoted as E max ; the corrected position P i , E i , R i , and the corresponding electromagnetic valve combination are obtained; according to the actual position P E of the clutch at the time of overmodulation, the position interval in which P E is located is determined, the position sequence i is determined, P i , E i , R i are obtained; then, according to P i , E i , R i , the original electromagnetic valve combination mode is determined.

[0061] S ni is determined according to the following electromagnetic valve combination mode matrix: ; The new electromagnetic valve combination mode is obtained:

[0062] ; Wherein, e1 is the first clutch position deviation threshold, e2 is the second clutch position deviation threshold, e3 is the third clutch position deviation threshold, e1, e2, e3 are set according to the actual situation.

[0063] For example: assuming that the clutch is engaged from 12mm to 0mm, the clutch stroke is 12mm, the actual position of the clutch is 0mm when it is fully compressed, and the position is 12mm when the clutch is fully separated; the actual position P of the clutch, the clutch position deviation E, the clutch target position change rate R corresponding to the preset control strategy of the electromagnetic valve control state matrix during the engagement process of the clutch are recorded in sequence as follows:

[0064] Thres1: interval threshold; For example:

[0065] Overmodulation detection, when the clutch has overmodulation, ;

[0066] For example: ; ; Get new electromagnetic valve combination way:

[0067] For example: .

[0068] That is, the new electromagnetic valve combination way is: .

[0069] Before correction, P6, E6, R6 use Electromagnetic valve combination way, that is, the exhaust large valve is fully open, and the exhaust small valve is closed, at this time, overshoot occurs, after correction, P6, E6, R6 use That is, the exhaust large valve is closed, and the exhaust small valve is fully open.

[0070] The present application controls the electromagnetic valve in a dynamic combination manner according to the actual position of the clutch, the clutch position deviation, and the clutch target position change rate, and adjusts the electromagnetic valve combination manner to eliminate overshoot when the system overshoots, thereby improving the stability and consistency of system control. Figure 5 and Figure 6 As shown in the figures, when overshoot occurs in the clutch combination process, the control stability is improved by adaptively and dynamically adjusting the electromagnetic valve combination control manner to eliminate the overshoot.

[0071] In order to better implement the electromagnetic valve control method in the embodiments of the present application, on the basis of the electromagnetic valve control method, as shown in Figure 7 , the present application also correspondingly provides an electronic control device 700. The electronic control device 700 includes a processor 701 and a memory 702. Figure 7 Only part of the components of the electronic control device 700 are shown, but it should be understood that it is not required to implement all the shown components, and more or fewer components can be alternatively implemented.

[0072] The processor 701 can be a central processing unit (CPU), a microprocessor or other data processing chip in some embodiments, used to run the program code or process data stored in the memory 702, such as the electromagnetic valve control method in the present application.

[0073] In some embodiments, memory 702 may be an internal storage device of electronic control device 700, such as a hard disk or memory of electronic control device 700. In other embodiments, memory 702 may also be an external storage device of electronic control device 700, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. equipped on electronic control device 700.

[0074] Furthermore, the memory 702 may include both internal and external storage devices of the electronic control device 700. The memory 702 is used to store application software and various types of data for which the electronic control device 700 is installed.

[0075] In one embodiment, when the processor 701 executes the solenoid valve control program in the memory 702, the following steps can be implemented: Obtain the target position, actual position, and rate of change of the target position of the clutch; Based on the position deviation, the actual position, the target position change rate, and a preset control strategy, at least two solenoid valves with different orifice diameters are controlled to perform a first combined action to drive the clutch to perform an engagement or disengagement operation; the position deviation is equal to the difference between the actual position and the target position; When it is determined that the position of the clutch has overshooted based on the position deviation, the maximum overshoot amount in the current overshoot event is obtained; The second combined action is determined based on the threshold range where the maximum overshoot is located; the second combined action is different from the first combined action, and the solenoid valves controlled by the first combined action and the second combined action are of the same type; Control at least two solenoid valves with different orifice diameters to perform the second combined action.

[0076] It should be understood that when the processor 701 executes the solenoid valve control program in the memory 702, in addition to the functions mentioned above, it can also perform other functions, as detailed in the description of the corresponding method embodiments above.

[0077] Accordingly, embodiments of this application also provide a vehicle clutch control system, including: Pneumatically driven clutch; At least two solenoid valves with different orifice diameters are used to control the gas flow rate into or out of the clutch; like Figure 7 The electronic control device is used to control the operation of the solenoid valve.

[0078] Those skilled in the art can understand that all or part of the processes of the above-mentioned embodiment methods can be completed by instructing the relevant hardware (such as a processor, a controller, etc.) through a solenoid control program in an electronic control device, and the solenoid control program can be stored in a computer readable storage medium. The computer readable storage medium is a magnetic disk, an optical disk, a read-only memory or a random access memory, etc.

[0079] The solenoid control method, the device and the vehicle clutch control system provided by the present application are described in detail above, and the principles and implementation manners of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, the specific implementation manners and application ranges will be changed according to the idea of the present application. In summary, the content of the description should not be understood as a limitation of the present application.

Claims

1. A solenoid valve control method characterized by, The method comprises: acquiring a target position, an actual position, and a target position change rate of a clutch; controlling at least two solenoid valves with different apertures to perform a first combined action based on a position deviation, the actual position, the target position change rate, and a preset control strategy, so as to drive the clutch to perform a combination or separation operation; the position deviation is equal to a difference between the actual position and the target position; when it is determined according to the position deviation that the position of the clutch overshoots, acquiring a maximum overshoot amount in a current overshoot event; determining a second combined action according to a threshold range in which the maximum overshoot amount is located; the second combined action is different from the first combined action, and the first combined action and the second combined action control the same type of solenoid valve; controlling at least two solenoid valves with different apertures to perform the second combined action.

2. The electromagnetic valve control method according to claim 1, characterized by, The preset control strategy is determined by: dividing a stroke of the clutch into a plurality of continuous position intervals; presetting a corresponding combined action for each position interval, and the combined action is determined by the actual position of the clutch, the position deviation, and the target position change rate.

3. The electromagnetic valve control method according to claim 2, characterized by, The acquiring of the maximum overshoot amount in the current overshoot event comprises: starting to detect overshoot from any one of the position intervals, and continuously monitoring the position deviation; determining a maximum absolute value of the position deviation that occurs during overshoot as the maximum overshoot amount.

4. The electromagnetic valve control method according to claim 2 or 3, characterized by, The determining of the second combined action according to the threshold range in which the maximum overshoot amount is located comprises: determining an overshoot position interval corresponding to the actual position of the clutch when the overshoot occurs; obtaining an original combined action corresponding to the overshoot position interval according to the preset control strategy; according to the maximum overshoot amount, offsetting a serial number of the original combined action by N positions to obtain a serial number of the second combined action, N being a positive integer.

5. The electromagnetic valve control method according to claim 4, characterized by, The offset rule is: if 0 < |E_max| ≤ e1, N = 1; if e1 < |E_max| ≤ e2, N = 2; if e2 < |E_max| ≤ e3, N = 3; wherein e1, e2, and e3 are preset clutch position deviation thresholds, and e1 < e2 < e3, and |E_max| is an absolute value of the maximum overshoot amount.

6. The electromagnetic valve control method according to claim 4, characterized by, The combined action is defined by a solenoid valve control state matrix, a row of the solenoid valve control state matrix corresponds to a combined action serial number of different solenoid valves, and a column corresponds to a switch state of different solenoid valves, and the switch state includes full opening, PWM control, and closing.

7. The solenoid valve control method according to claim 1, wherein: when the clutch performs a combination operation, the solenoid valve is an exhaust solenoid valve; when the clutch performs a separation operation, the solenoid valve is an intake solenoid valve.

8. The electromagnetic valve control method according to claim 1, characterized by, The determining of the overshoot of the position of the clutch according to the position deviation comprises: when the position deviation is greater than zero during the combination of the clutch, it is determined that the overshoot occurs; when the position deviation is less than zero during the separation of the clutch, it is determined that the overshoot occurs.

9. An electronic control device, characterized by A computer program product comprising a memory and a processor, wherein The memory is configured to store a program. The processor is coupled to the memory and configured to execute the program stored in the memory to implement the steps of the solenoid control method of any one of claims 1 to 8.

10. A vehicle clutch control system characterized by, Comprising: A pneumatically driven clutch; At least two solenoids of different orifice sizes for controlling the flow of gas into or out of the clutch; An electronic control device as claimed in claim 9 for controlling the operation of the solenoids.

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