Method and controller for controlling gear shifting of gearbox, operation machine and storage medium

Abstract

The invention discloses a method for controlling gear shifting of a gearbox, a controller, an operation machine and a storage medium. The method comprises the steps that the real-time hydraulic oil temperature of the gearbox is obtained; based on the real-time hydraulic oil temperature, a preset electromagnetic valve control current curve is adjusted to obtain a target electromagnetic valve control current curve; based on the real-time hydraulic oil temperature, model parameters of a preset electromagnetic valve dynamic model are updated, and the preset electromagnetic valve dynamic model is used for representing the dynamic relation between the electromagnetic valve control current and the gearbox oil pressure; performing feedforward compensation on the target electromagnetic valve control current curve through the updated preset electromagnetic valve dynamic model to obtain an actual electromagnetic valve control current curve; and a gear shifting electromagnetic valve is controlled according to the actual electromagnetic valve control current curve, so that gear shifting operation of the gearbox is completed. According to the method, the electromagnetic valve control current curve and the parameters of the preset electromagnetic valve dynamic model are synchronously and dynamically corrected based on the hydraulic oil temperature, and smooth gear shifting under all working conditions is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of working machines, in particular to a method for controlling gear shifting of a gearbox, a controller, a working machine and a storage medium. BACKGROUND

[0002] As a key transmission component of wheeled and tracked working machines, the gear shifting quality of a hydraulic automatic gearbox directly affects the operating comfort and working reliability of the whole machine. In actual operation, due to the influence of comprehensive factors such as hydraulic oil temperature change, oil pressure fluctuation, friction coefficient difference and complex working conditions, gear shifting impact problems exist in the gearbox, which seriously affects the driving experience and component life.

[0003] At present, in order to alleviate the gear shifting impact, a common strategy in the industry is to optimize the control current curve of the electromagnetic valve to realize the flexible transmission of hydraulic buffering and torque. However, the effectiveness of this method depends heavily on the established oil pressure-current characteristic curve of the electromagnetic valve. In actual use, this characteristic will drift due to electromagnetic valve wear, oil temperature change and individual differences between components, resulting in the preset current curve not accurately corresponding to the target oil pressure. Even if the current curve is carefully optimized, the actual pressure building will still deviate from the ideal trajectory, causing gear shifting impact.

[0004] Therefore, the gear shifting control method used in the prior art has poor gear shifting smoothness and has the problem of easy gear shifting impact. SUMMARY

[0005] The purpose of the embodiments of the present application is to provide a method for controlling gear shifting of a gearbox, a controller, a working machine and a machine readable storage medium, to solve the problem of poor gear shifting smoothness and easy gear shifting impact of the gear shifting control method used in the prior art.

[0006] In order to achieve the above-mentioned purpose, the first aspect of the present application provides a method for controlling gear shifting of a gearbox, applied to a working machine, the working machine comprising a gearbox and a gear shifting electromagnetic valve, the gear shifting electromagnetic valve being used to control the gearbox to perform gear shifting operation, the method comprising: obtaining the real-time hydraulic oil temperature of the gearbox; based on the real-time hydraulic oil temperature, adjusting the preset electromagnetic valve control current curve to obtain a target electromagnetic valve control current curve; based on the real-time hydraulic oil temperature, updating the model parameters of a preset electromagnetic valve dynamic model, the preset electromagnetic valve dynamic model being used to represent the dynamic relationship between the electromagnetic valve control current and the gearbox oil pressure; performing feedforward compensation on the target electromagnetic valve control current curve through the updated preset electromagnetic valve dynamic model to obtain an actual electromagnetic valve control current curve; The shift solenoid valve is controlled according to an actual solenoid valve control current curve to complete the gear shifting operation of the gearbox.

[0007] In the embodiment of the present application, the target solenoid valve control current curve is fed forwardly compensated by the updated preset solenoid valve dynamic model to obtain an actual solenoid valve control current curve, comprising: Based on the solenoid valve dynamic model updated by the model parameters, the corresponding inverse model is obtained by model inversion operation; The target solenoid valve control current curve is fed forwardly compensated based on the inverse model to obtain the compensated actual solenoid valve control current curve.

[0008] In the embodiment of the present application, the model parameters include a proportional coefficient, a time constant and a lag time; The determination of the actual solenoid valve control current curve satisfies formula (1): ; (1) In the formula, is the actual solenoid valve control current curve, is the updated proportional coefficient, is the updated time constant, is the Laplace operator, is the target solenoid valve control current curve, is the updated lag time, and t is a time axis parameter.

[0009] In the embodiment of the present application, the model parameters include a proportional coefficient, a time constant and a lag time; Based on the real-time hydraulic oil temperature, the model parameters of the preset solenoid valve dynamic model are updated, comprising: According to the preset basic proportional coefficient and the real-time hydraulic oil temperature, the updated proportional coefficient is determined; According to the preset basic time constant and the real-time hydraulic oil temperature, the updated time constant is determined; According to the preset basic lag time and the real-time hydraulic oil temperature, the updated lag time is determined.

[0010] In the embodiment of the present application, the determination of the updated proportional coefficient satisfies formula (2): ; (2) In the formula, is the updated proportional coefficient, is the preset basic proportional coefficient, is the real-time hydraulic oil temperature, is the first preset compensation coefficient, is the first preset reference oil temperature; The determination of the updated time constant satisfies formula (3): (3) In the formula, The updated time constant, To preset the basic time constant, For real-time hydraulic oil temperature, This is the second preset compensation coefficient. This is the second preset reference oil temperature; The updated lag time is determined according to formula (4): (4) In the formula, The updated lag time. To preset the base lag time, For real-time hydraulic oil temperature, This is the third preset compensation coefficient. This is the third preset reference oil temperature.

[0011] In this embodiment, the preset solenoid valve control current curve includes a rapid filling stage and a buffer torque change stage; Based on real-time hydraulic oil temperature, the preset solenoid valve control current curve is adjusted to obtain the target solenoid valve control current curve, including: Based on the real-time hydraulic oil temperature, the oil pressure slope in the rapid filling stage and the buffer torque change stage of the preset solenoid valve control current curve is corrected. The corrected solenoid valve control current curve is used as the target solenoid valve control current curve.

[0012] In this embodiment, the oil pressure slope of the rapid filling stage and the buffer torque change stage in the preset solenoid valve control current curve is corrected according to the real-time hydraulic oil temperature, including: The real-time hydraulic oil temperature is matched with the first preset temperature range, the second preset temperature range, the third preset temperature range, and the fourth preset temperature range, respectively. When the real-time hydraulic oil temperature is within the first preset temperature range, the oil pressure slope during the rapid filling stage is increased by a first preset percentage, and the oil pressure slope during the buffer torque change stage is decreased by a second preset percentage. When the real-time hydraulic oil temperature is within the second preset temperature range, the oil pressure slope during the rapid filling stage is increased by a third preset percentage, and the oil pressure slope during the buffer torque change stage is decreased by a fourth preset percentage. The first preset percentage is greater than the third preset percentage, and the second preset percentage is greater than the fourth preset percentage. When the real-time hydraulic oil temperature is within the third preset temperature range, maintain the oil pressure slope during the rapid filling phase and the buffer torque change phase. When the real-time hydraulic oil temperature is within the fourth preset temperature range, reduce the oil pressure slope during the rapid filling stage and increase the oil pressure slope during the buffer torque change stage. Among them, the fourth preset temperature range is higher than the third preset temperature range, the third preset temperature range is higher than the second preset temperature range, and the second preset temperature range is higher than the first temperature range.

[0013] A second aspect of this application provides a controller, comprising: The memory is configured to store instructions; and The processor is configured to retrieve instructions from memory and, when executing the instructions, to implement the aforementioned method for controlling gearbox shifting.

[0014] A third aspect of this application provides a work machine, comprising: The aforementioned controller; gearbox; The shift solenoid valve is used to control the gearbox to perform shift operations.

[0015] The fourth aspect of this application provides a machine-readable storage medium on which a program or instructions are stored, and when the program or instructions are executed by a processor, the above-described method for controlling gearbox shifting is implemented.

[0016] The above technical solution first obtains the real-time hydraulic oil temperature of the transmission. Then, based on the real-time hydraulic oil temperature, it adjusts the preset solenoid valve control current curve to obtain the target solenoid valve control current curve. Simultaneously, based on the real-time hydraulic oil temperature, it updates the model parameters of the preset solenoid valve dynamic model. The preset solenoid valve dynamic model is used to characterize the dynamic relationship between the solenoid valve control current and the transmission oil pressure. Next, it performs feedforward compensation on the target solenoid valve control current curve using the updated preset solenoid valve dynamic model to obtain the actual solenoid valve control current curve. Finally, it controls the shift solenoid valve according to the actual solenoid valve control current curve to complete the transmission shifting operation. This application solves the shifting shock problem caused by the coupling of system characteristic drift and response lag by synchronously and dynamically correcting the parameters of the solenoid valve control current curve and the preset solenoid valve dynamic model based on hydraulic oil temperature, and achieves smooth shifting under all operating conditions.

[0017] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings: Figure 1A flowchart illustrating a method for controlling gearbox shifting provided in an embodiment of this application; Figure 2 A schematic diagram of a preset solenoid valve control current curve provided in a specific embodiment of this application; Figure 3 A structural block diagram of a controller provided in an embodiment of this application; Figure 4 This is a structural block diagram of a gearbox shift control system provided for a specific implementation of this application. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the embodiments of this application and are not intended to limit the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0020] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0021] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0022] Figure 1 This is a flowchart illustrating a method for controlling gearbox shifting according to an embodiment of this application. Figure 1 As shown in the figure, this application provides a method for controlling gearbox shifting, which is applied to a work machinery. The work machinery includes a gearbox and a shift solenoid valve. The shift solenoid valve is used to control the gearbox to perform shifting operations. Taking the application of this method to the controller of the work machinery as an example, the method may include the following steps.

[0023] Step S101: Obtain the real-time hydraulic oil temperature of the transmission.

[0024] It is understandable that hydraulic oil temperature is one of the key factors affecting the shifting performance of a transmission. Changes in oil temperature directly alter the viscosity of the hydraulic oil and the dynamic response characteristics of the solenoid valve. For example, in low-temperature environments, the viscosity of the hydraulic oil increases, leading to a slower response and reduced pressure build-up speed of the solenoid valve; while in high-temperature environments, the viscosity of the oil decreases, potentially reducing the coefficient of friction between the friction plates and making shifting shocks or slippage more likely. Therefore, this application proposes a Smith predictive control strategy based on oil temperature compensation by comprehensively considering the impact of hydraulic oil temperature on the performance of the solenoid valve and the hysteresis characteristics of the control system, in order to achieve smoothness and reliability in the shifting process.

[0025] Specifically, to achieve oil temperature acquisition, the operating machinery is usually equipped with a transmission oil temperature sensor, which transmits the detected temperature signal to the vehicle controller in real time. The vehicle controller receives the temperature information sent by the transmission temperature sensor, processes it, and obtains the real-time hydraulic oil temperature.

[0026] Step S102: Based on the real-time hydraulic oil temperature, adjust the preset solenoid valve control current curve to obtain the target solenoid valve control current curve.

[0027] In this embodiment, the preset solenoid valve control current curve refers to a set of standard current control instructions stored in the controller memory, which represents the ideal trajectory of the solenoid valve drive current changing over time in order to complete a smooth gear shifting operation under an ideal reference temperature; the target solenoid valve control current curve is an optimized ideal control instruction that is suitable for the current operating condition and is obtained by correcting the preset curve based on the real-time oil temperature.

[0028] Because the viscosity of hydraulic oil decreases with increasing temperature and increases with decreasing temperature, this viscosity change directly affects the pressure build-up speed of the hydraulic system and the response characteristics of the solenoid valve. In this situation, if a fixed preset solenoid valve control current curve is consistently used for shift control, shift shock will still occur, and the wear of the clutch friction plates will be aggravated. Therefore, to adapt to the control requirements across the entire operating range, this application embodiment can dynamically correct the preset solenoid valve control current curve based on the hydraulic oil temperature to obtain the target solenoid valve control current curve. In one example, a mapping relationship between hydraulic oil temperature and the current curve can be pre-established and stored in the system. The subsequent processor can then dynamically adjust the preset solenoid valve control current curve based on this mapping relationship and the real-time hydraulic oil temperature, ensuring that it always matches the actual dynamic characteristics of the hydraulic system. This allows the current command to actively match the oil state, significantly improving the smoothness of subsequent shifts.

[0029] Step S103: Based on the real-time hydraulic oil temperature, update the model parameters of the preset solenoid valve dynamic model. The preset solenoid valve dynamic model is used to characterize the dynamic relationship between the solenoid valve control current and the transmission oil pressure.

[0030] In this embodiment, the lag problem in the establishment of the controller output current curve and the pressure curve is addressed using temperature-adaptive Smith predictor control. The Smith predictor is an advanced controller specifically designed for systems with lag, its core consisting of an internal model, a lag compensation mechanism, and feedback correction. This embodiment uses a preset solenoid valve dynamic model as the internal model of the Smith predictor. This preset solenoid valve dynamic model describes the dynamic causal relationship between the solenoid valve control current and the transmission oil pressure. The model parameters of the preset solenoid valve dynamic model include the proportional gain, time constant, and lag time.

[0031] It is understandable that the controlled object, consisting of the shift solenoid valve and the hydraulic system, has dynamic characteristics that strongly depend on the hydraulic oil temperature. The viscosity of the hydraulic oil decreases significantly with increasing temperature, which directly affects the flow resistance and response speed of the oil in the valve body and pipelines. In this case, if the Smith predictor always uses a set of basic model parameters calibrated at a fixed temperature, then when the actual oil temperature deviates from the calibration temperature, the predicted output of the internal model will deviate significantly from the actual response of the system, causing the Smith predictor's compensation to fail and shift shocks to still occur. To address this problem, the embodiments of this application can update the model parameters in real time based on the real-time hydraulic oil temperature to ensure that the internal dynamic model of the Smith predictor can always accurately simulate the actual behavior of the solenoid valve and hydraulic system at the current oil temperature.

[0032] Specifically, the processor can update the model parameters of the preset solenoid valve dynamic model based on the real-time hydraulic oil temperature. In one example, a mapping relationship between oil temperature and model parameters can be established in advance. During the system development phase, by applying a step current signal to the solenoid valve under different oil temperature conditions on a test bench or in a real vehicle and collecting the response data of current and oil pressure, the proportional coefficient, time constant, and lag time of the dynamic model at each temperature point can be identified. Then, these data are fitted into a parametric function with oil temperature as the independent variable or made into a lookup table and stored in the memory of the vehicle controller. During actual operation, the controller can obtain or calculate the updated model parameters corresponding to the current temperature in real time by looking up the table or calculating the corresponding parametric function based on the real-time hydraulic oil temperature.

[0033] In this way, the model parameters are dynamically adjusted according to the changes in oil temperature, enabling the predictor to make accurate future predictions and provide the controller with the correct advance compensation signal, thereby effectively offsetting system lag and achieving precise control.

[0034] Step S104: Feedforward compensation is performed on the target solenoid valve control current curve using the updated preset solenoid valve dynamic model to obtain the actual solenoid valve control current curve.

[0035] In this embodiment, the actual solenoid valve control current curve is the final execution instruction generated after feedforward compensation by the Smith predictor, which already includes accurate compensation for the system's hysteresis characteristics.

[0036] Specifically, after the controller corrects the solenoid valve control current curve and model parameters based on hydraulic oil temperature, it can input the target solenoid valve control current curve into the updated Smith predictor. The Smith predictor's internal preset solenoid valve dynamic model simulates the ideal response of the solenoid valve and hydraulic system, calculating the expected oil pressure curve without considering lag. Then, the compensation stage considers the system's pure lag time, advancing the target current curve by the corresponding lag amount on the time axis. Specifically, for each current command at any given time point, the predictor issues the command a corresponding time ahead based on the updated lag time parameters. Simultaneously, the predictor also appropriately scales and corrects the current amplitude based on the updated proportional gain and time constant parameters to compensate for the impact of changes in system dynamic characteristics, ultimately obtaining the actual solenoid valve control current curve. In this way, system lag and dynamic response deviations can be accurately offset, achieving precise synchronization between control commands and system responses.

[0037] Step S105: Control the shift solenoid valve according to the actual solenoid valve control current curve to complete the gearbox shifting operation.

[0038] Specifically, after obtaining the actual solenoid valve control current curve, the controller can output current to the shift solenoid valve according to the actual solenoid valve control current curve, so that the shift solenoid valve generates the corresponding electromagnetic force according to the control current, accurately adjusts the valve core opening, thereby controlling the hydraulic oil flow and pressure to the gearbox clutch piston, and finally realizes the smooth engagement and disengagement of the clutch to complete the gear shift.

[0039] The above technical solution first obtains the real-time hydraulic oil temperature of the transmission. Then, based on the real-time hydraulic oil temperature, it adjusts the preset solenoid valve control current curve to obtain the target solenoid valve control current curve. Simultaneously, based on the real-time hydraulic oil temperature, it updates the model parameters of the preset solenoid valve dynamic model. The preset solenoid valve dynamic model is used to characterize the dynamic relationship between the solenoid valve control current and the transmission oil pressure. Next, it performs feedforward compensation on the target solenoid valve control current curve using the updated preset solenoid valve dynamic model to obtain the actual solenoid valve control current curve. Finally, it controls the shift solenoid valve according to the actual solenoid valve control current curve to complete the transmission shifting operation. This application solves the shifting shock problem caused by the coupling of system characteristic drift and response lag by synchronously and dynamically correcting the parameters of the solenoid valve control current curve and the preset solenoid valve dynamic model based on hydraulic oil temperature, and achieves smooth shifting under all operating conditions.

[0040] In this embodiment, the preset solenoid valve control current curve includes a rapid filling stage and a buffer torque change stage; adjusting the preset solenoid valve control current curve based on the real-time hydraulic oil temperature to obtain the target solenoid valve control current curve may include: Based on the real-time hydraulic oil temperature, the oil pressure slope in the rapid filling stage and the buffer torque change stage of the preset solenoid valve control current curve is corrected. The corrected solenoid valve control current curve is used as the target solenoid valve control current curve.

[0041] In this embodiment, the preset solenoid valve control current curve is a time-current curve. Figure 2 This is a schematic diagram of a preset solenoid valve control current curve provided in a specific embodiment of this application. Figure 2As shown, the solenoid valve control current curve can be divided into four consecutive stages, each corresponding to a specific physical process during clutch engagement. Stage 1 is the rapid filling stage, designed to quickly fill the clutch cylinder with hydraulic oil to eliminate the physical gap between the clutch friction plates and steel plates. This stage typically corresponds to a rapid rise in current and a high oil pressure slope; for example, rapid current loading can achieve a rapid increase in transmission shift pressure at a slope of 4 MPa / s. Stage 2 is the buffered torque change stage, a critical period for the clutch to begin engaging and transmitting torque. By controlling the current to increase slowly, the oil pressure rises smoothly to limit sudden torque changes and prevent shocks; for example, smooth current loading can achieve a slow change in transmission shift pressure at a slope of 0.5 MPa / s to limit sudden torque changes. Stage 3 is the torque holding stage, which maintains a constant current to ensure stable torque transmission under slipping conditions, ensuring a smooth transition during gear shifts. Phase four is the full lock-up phase. In this phase, a rapid increase in current causes the oil pressure to quickly reach its maximum value, achieving full clutch engagement and locking. For example, a rapid current load causes the transmission shift pressure to rise rapidly at a slope of 2 MPa / s to reach the final pressure required for shifting. The oil pressure slope refers to the clutch oil pressure build-up rate indirectly controlled by the solenoid valve's current change rate, i.e., the rate of change of hydraulic pressure per unit time, determined by the solenoid valve's current change rate.

[0042] Specifically, since the impact of hydraulic oil temperature changes on the dynamic characteristics of different stages during clutch engagement is not homogeneous, the processor can correct the oil pressure slope of the preset solenoid valve control current curve for the rapid filling stage and the buffer torque change stage based on the real-time hydraulic oil temperature. For example, at low temperatures, the oil viscosity is high, requiring greater force to overcome flow resistance during the rapid filling stage to shorten the filling time; however, during the buffer torque change stage, the high-viscosity oil itself has a damping effect, and if the slope is the same as at room temperature, the engagement process may be too abrupt, necessitating a reduction in the slope for buffering. Conversely, at high temperatures, the oil is thin, and rapid filling can easily generate hydraulic shock, while the buffer stage requires faster pressure build-up to prevent excessive slippage due to the decreased friction coefficient. Therefore, differentiated oil temperature compensation for the physical characteristics of different stages allows the dynamic characteristics of the clutch in each engagement sub-process to achieve optimal matching with the current oil temperature, thus maintaining optimal performance throughout the entire engagement sequence.

[0043] In this embodiment, correcting the oil pressure slope of the rapid filling phase and the buffer torque change phase in the preset solenoid valve control current curve based on the real-time hydraulic oil temperature may include: The real-time hydraulic oil temperature is matched with the first preset temperature range, the second preset temperature range, the third preset temperature range, and the fourth preset temperature range, respectively. When the real-time hydraulic oil temperature is within the first preset temperature range, the oil pressure slope during the rapid filling stage is increased by a first preset percentage, and the oil pressure slope during the buffer torque change stage is decreased by a second preset percentage. When the real-time hydraulic oil temperature is within the second preset temperature range, the oil pressure slope during the rapid filling stage is increased by a third preset percentage, and the oil pressure slope during the buffer torque change stage is decreased by a fourth preset percentage. The first preset percentage is greater than the third preset percentage, and the second preset percentage is greater than the fourth preset percentage. When the real-time hydraulic oil temperature is within the third preset temperature range, maintain the oil pressure slope during the rapid filling phase and the buffer torque change phase. When the real-time hydraulic oil temperature is within the fourth preset temperature range, reduce the oil pressure slope during the rapid filling stage and increase the oil pressure slope during the buffer torque change stage. Among them, the fourth preset temperature range is higher than the third preset temperature range, the third preset temperature range is higher than the second preset temperature range, and the second preset temperature range is higher than the first temperature range.

[0044] In this embodiment, the first to fourth preset temperature ranges are hydraulic oil temperature ranges pre-divided according to actual conditions. The boundary values ​​and corresponding slope correction percentages of each temperature range are obtained through extensive bench tests and real vehicle tests. For example, the first preset temperature range refers to the low-temperature operating range, -30℃ to 0℃; the second preset temperature range refers to the medium-low temperature operating range, 0℃ to 40℃; the third preset temperature range refers to the normal operating temperature range, 40℃ to 100℃; and the fourth preset temperature range refers to the high-temperature operating range, 100℃ to 130℃. There is no overlap between the preset temperature ranges on the temperature scale.

[0045] It is understandable that the characteristics of hydraulic oil change drastically with temperature, significantly impacting the shifting process. At low temperatures, oil viscosity increases significantly, leading to increased flow resistance. This necessitates increasing the slope during the rapid filling phase to accelerate the filling process. Simultaneously, the high viscosity of the oil naturally creates significant damping during the buffering phase, requiring a reduced slope to avoid torque shock. At high temperatures, oil viscosity decreases, resulting in excessive fluidity. This necessitates reducing the rapid filling slope to prevent hydraulic shock. Furthermore, the friction coefficient of the friction plates decreases, requiring an increased slope during the buffering phase to ensure rapid torque build-up. The fundamental purpose is to address the primary contradictions across different temperature ranges through precise differential compensation, achieving smooth shifting across the entire operating range. To this end, embodiments of this application employ opposite slope correction strategies in different temperature ranges, precisely addressing the core contradictions such as flow resistance at low temperatures and the decrease in friction coefficient at high temperatures, thereby achieving stable and smooth shifting operation across the entire operating range.

[0046] In one specific embodiment, the specific temperature range and corresponding adjustment strategy for each preset temperature range can be as follows: The first preset temperature range is -30℃ to 0℃, increasing the oil pressure slope by 8% during the rapid filling phase and decreasing it by 12% during the buffer torque change phase; the preset ambient temperature range is 0℃ to 40℃, increasing the oil pressure slope by 5% during the rapid filling phase and decreasing it by 5% during the buffer torque change phase; the preset normal operating temperature range is 40℃ to 100℃, maintaining the oil pressure slope at the baseline value during both the rapid filling and buffer torque change phases; the second preset temperature range is 100℃ to 130℃, decreasing the oil pressure slope by 3% during the rapid filling phase and increasing it by 7% during the buffer torque change phase. These values ​​are merely illustrative and can be calibrated according to actual conditions. In this way, temperature-adaptive optimization of the control strategy is achieved. Through targeted reverse correction, both shift response speed under low-temperature conditions and operational smoothness under high-temperature conditions are ensured.

[0047] In this embodiment, feedforward compensation is performed on the target solenoid valve control current curve using an updated preset solenoid valve dynamic model to obtain the actual solenoid valve control current curve. This may include: Based on the updated model parameter dynamic model of the solenoid valve, the corresponding inverse model is obtained through inverse model operation; Feedforward compensation is performed on the control current curve of the target solenoid valve based on the inverse model to obtain the actual control current curve of the solenoid valve after compensation.

[0048] It is understandable that traditional feedback control struggles to achieve precise timing synchronization due to the inherent dynamic hysteresis of solenoid valve systems. To address this, this application's embodiments utilize feedforward compensation by constructing an inverse model, theoretically eliminating deviations caused by the system's dynamic characteristics in advance. This allows the actual oil pressure response to accurately track the target curve, thereby achieving precise control of the gear shifting process.

[0049] Specifically, the corresponding inverse model expression is first calculated based on the updated model parameters, and then the target solenoid valve current curve is input into the inverse model. The inverse model processes the current command with phase lead and amplitude correction, ultimately generating an actual solenoid valve control current curve that has compensated for the system's dynamic characteristics. For example, for a system with hysteresis characteristics, the inverse model will appropriately advance the current command on the time axis.

[0050] In this way, by replacing empirical debugging with mathematical model calculations, the adaptability and consistency of the system are enhanced, and the accuracy of gearbox control is improved.

[0051] In this embodiment, the model parameters may include a proportional coefficient, a time constant, and a lag time; the determination of the actual solenoid valve control current curve can satisfy formula (1): (1) In the formula, This is the actual control current curve of the solenoid valve. This is the updated scaling factor. The updated time constant, For the Laplace operator, ( ) represents the control current curve of the target solenoid valve. The updated lag time. t These are the time axis parameters.

[0052] In this embodiment, the model parameters may include a proportional coefficient, a time constant, and a lag time; updating the model parameters of the preset solenoid valve dynamic model based on the real-time hydraulic oil temperature may include: The updated proportional coefficient is determined based on the preset basic proportional coefficient and the real-time hydraulic oil temperature; The updated time constant is determined based on the preset base time constant and the real-time hydraulic oil temperature; The updated lag time is determined based on the preset basic lag time and the real-time hydraulic oil temperature.

[0053] In this embodiment, the proportional gain reflects the steady-state gain of the system, i.e., the maximum oil pressure that can be generated per unit current; the time constant characterizes the system response speed and determines how quickly the oil pressure is established; the lag time refers to the delay period from the issuance of the current command to the start of the oil pressure response. The preset basic parameters refer to the reference model parameter values ​​calibrated at standard temperatures.

[0054] Since the properties of hydraulic oil change significantly with temperature, affecting the dynamic response of the solenoid valve, a prediction model with fixed parameters will lead to inaccurate predictions. To address this, the embodiments of this application establish a mapping relationship between temperature and various model parameters, enabling the Smith predictor to track changes in the system's dynamic characteristics in real time, ensuring that the prediction model always matches the actual system.

[0055] In one example, the controller internally stores a table mapping model parameters to oil temperature. This table is established by conducting system identification experiments at multiple different temperature points, measuring and recording the optimal model parameter values ​​for each temperature point. During system operation, the controller queries the proportional gain correction value, time constant correction value, and lag time correction value corresponding to the current real-time hydraulic oil temperature, combines these correction values ​​with their respective basic parameters, and calculates the proportional gain, time constant, and lag time applicable to the current temperature.

[0056] In another example, the controller can have a built-in model showing the relationship between parameters and temperature. For instance, the proportional gain model can be set as a linear function, the time constant model can use an exponential relationship, and the lag time model can use a polynomial fit. The controller calculates updated values ​​for the three parameters based on the real-time oil temperature, obtaining the updated proportional gain, updated time constant, and updated lag time. This provides an accurate and reliable model foundation for feedforward compensation, ultimately ensuring smooth shifting across the entire temperature range.

[0057] In this embodiment of the application, the preset scaling factor model can satisfy formula (2): (2) In the formula, This is the updated scaling factor. To preset the basic ratio coefficient, For real-time hydraulic oil temperature, The first preset compensation coefficient is... This is the first preset reference oil temperature.

[0058] In this embodiment of the application, the preset time constant model can satisfy formula (3): (3) In the formula, The updated time constant, To preset the basic time constant, For real-time hydraulic oil temperature, This is the second preset compensation coefficient. This is the second preset reference oil temperature.

[0059] In this embodiment of the application, the preset lag time model can satisfy formula (4): (4) In the formula, The updated lag time. To preset the base lag time, For real-time hydraulic oil temperature, This is the third preset compensation coefficient. This is the third preset reference oil temperature.

[0060] It is understandable that the aforementioned preset compensation coefficient and preset reference oil temperature can be determined by dynamically testing the solenoid valve system at different oil temperatures, collecting current-oil pressure response data, and then using mathematical methods such as system identification and linear regression to fit the model parameters to determine their temperature variation. For example... =0.0012, =80, =0.0012, =80, =0.0015, =40.

[0061] In this way, by establishing a precise mathematical relationship between model parameters and hydraulic oil temperature, the Smith predictor can achieve full-condition adaptive tracking of the dynamic characteristics of the solenoid valve, thereby significantly improving the accuracy and smoothness of shift control.

[0062] In one specific embodiment, the control current curve of the solenoid valve based on oil temperature compensation can be described as the following loading function with respect to time, as shown in formula (5): (5) In this embodiment, the lag problem between the controller output current curve and the pressure settling curve is solved by temperature-adaptive Smith predictive control. Specifically, the lag time between the controller output current curve and the pressure settling curve at normal operating oil temperature is addressed. Establish a dynamic model of the solenoid valve as shown in formula (6): (6) Furthermore, by fitting the step response of the gear position control solenoid valve of the actual vehicle's transmission, the following was achieved: and The value is used to obtain the actual controller output current curve as shown in the following formula. As shown in formula (7): (7) Furthermore, the controller adjusts according to the hydraulic oil temperature. Real-time modification of solenoid valve control current And update the lag time between the controller output current curve and the pressure establishment curve. The proportional coefficient of the dynamic model of the solenoid valve With time constant The actual controller output current value is obtained based on the optimized control model. As shown in formula (1), this reduces the impact of gearbox shifting.

[0063] Figure 3 This is a structural block diagram of a controller provided in an embodiment of this application. Figure 3 As shown in the figure, this application provides a controller that may include: Memory 310 is configured to store instructions; and The processor 320 is configured to retrieve instructions from the memory 310 and, when executing the instructions, to implement the method for controlling gearbox shifting described above.

[0064] This application embodiment also provides a working machine, including: The controller in the above embodiments; gearbox; The shift solenoid valve is used to control the gearbox to perform shift operations.

[0065] Specifically, the control terminal of the shift solenoid valve is electrically connected to the signal output terminal of the controller, and the hydraulic output terminal of the shift solenoid valve is connected to the hydraulic control circuit of the transmission to control the transmission to perform shifting operations.

[0066] Figure 4 This is a structural block diagram of a gearbox shift control system provided for a specific embodiment of this application. Figure 4 As shown in a specific embodiment of this application, the transmission shift control system includes a vehicle controller, a reverse shift solenoid valve, a first-gear shift solenoid valve, a second-gear shift solenoid valve, a reverse oil pressure sensor, a first-gear oil pressure sensor, a second-gear oil pressure sensor, and a transmission oil temperature sensor. The vehicle controller establishes the transmission shift pressure curve and controls the engagement of the gear clutch by controlling the current of the solenoid valves, thereby realizing the transmission gear change. Simultaneously, closed-loop control is achieved through pressure feedback detection using the gear pressure sensor. The vehicle controller in this embodiment can implement the transmission shift control method described above. It detects hydraulic oil temperature changes using the hydraulic oil temperature sensor and adaptively compensates the shift solenoid valve current curve and the Smith predictor based on the oil temperature to reduce shift shock.

[0067] This application also provides a machine-readable storage medium on which a program or instruction is stored. When the program or instruction is executed by a processor, it implements the method for controlling gearbox shifting described above.

[0068] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0069] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0070] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0071] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0072] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0073] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, like read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0074] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0075] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0076] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for controlling gearbox shifting, characterized in that, The method, applied to operating machinery, includes a gearbox and a shift solenoid valve, wherein the shift solenoid valve controls the gearbox to perform a shifting operation, and the method includes: Obtain the real-time hydraulic oil temperature of the transmission; Based on the real-time hydraulic oil temperature, adjust the preset solenoid valve control current curve to obtain the target solenoid valve control current curve. Based on the real-time hydraulic oil temperature, the model parameters of the preset solenoid valve dynamic model are updated. The preset solenoid valve dynamic model is used to characterize the dynamic relationship between the solenoid valve control current and the transmission oil pressure. The target solenoid valve control current curve is fed forward by updating the preset solenoid valve dynamic model to obtain the actual solenoid valve control current curve. The shift solenoid valve is controlled according to the actual solenoid valve control current curve to complete the gearbox shifting operation.

2. The method according to claim 1, characterized in that, The step of performing feedforward compensation on the target solenoid valve control current curve using an updated preset solenoid valve dynamic model to obtain the actual solenoid valve control current curve includes: Based on the updated model parameter dynamic model of the solenoid valve, the corresponding inverse model is obtained through inverse model operation; Based on the inverse model, the control current curve of the target solenoid valve is fed forward to obtain the actual control current curve of the solenoid valve after compensation.

3. The method according to claim 2, characterized in that, The model parameters include the scaling factor, time constant, and lag time. The determination of the actual solenoid valve control current curve satisfies formula (1): ；（1） In the formula, This is the actual control current curve of the solenoid valve. The updated scaling factor, The updated time constant, For the Laplace operator, ( ) represents the control current curve of the target solenoid valve. The updated lag time is given, and t is a time axis parameter.

4. The method according to claim 1, characterized in that, The model parameters include the scaling factor, time constant, and lag time. The step of updating the model parameters of the preset solenoid valve dynamic model based on the real-time hydraulic oil temperature includes: The updated proportional coefficient is determined based on the preset basic proportional coefficient and the real-time hydraulic oil temperature; The updated time constant is determined based on the preset base time constant and the real-time hydraulic oil temperature; The updated lag time is determined based on the preset base lag time and the real-time hydraulic oil temperature.

5. The method according to claim 4, characterized in that, The determination of the updated scaling factor satisfies formula (2): ；（2） In the formula, The updated scaling factor, The preset basic ratio coefficient, The real-time hydraulic oil temperature, The first preset compensation coefficient is... The first preset reference oil temperature; The updated time constant is determined according to formula (3): ；（3） In the formula, The updated time constant, The preset basic time constant, The real-time hydraulic oil temperature, This is the second preset compensation coefficient. This is the second preset reference oil temperature; The determination of the updated lag time satisfies formula (4): ；（4） In the formula, The updated lag time. The preset base lag time, The real-time hydraulic oil temperature, This is the third preset compensation coefficient. This is the third preset reference oil temperature.

6. The method according to claim 1, characterized in that, The preset solenoid valve control current curve includes a rapid filling stage and a buffer torque change stage. The step of adjusting the preset solenoid valve control current curve based on the real-time hydraulic oil temperature to obtain the target solenoid valve control current curve includes: Based on the real-time hydraulic oil temperature, the oil pressure slope of the rapid filling stage and the buffer torque change stage in the preset solenoid valve control current curve is corrected. The corrected solenoid valve control current curve is used as the target solenoid valve control current curve.

7. The method according to claim 6, characterized in that, The step of correcting the oil pressure slope in the rapid filling phase and the buffer torque change phase of the preset solenoid valve control current curve based on the real-time hydraulic oil temperature includes: The real-time hydraulic oil temperature is matched with the first preset temperature range, the second preset temperature range, the third preset temperature range, and the fourth preset temperature range, respectively. When the real-time hydraulic oil temperature is within the first preset temperature range, the oil pressure slope of the rapid filling stage is increased by a first preset percentage, and the oil pressure slope of the buffer torque change stage is decreased by a second preset percentage. When the real-time hydraulic oil temperature is within the second preset temperature range, the oil pressure slope of the rapid filling stage is increased by a third preset percentage, and the oil pressure slope of the buffer torque change stage is decreased by a fourth preset percentage, wherein the first preset percentage is greater than the third preset percentage, and the second preset percentage is greater than the fourth preset percentage. When the real-time hydraulic oil temperature is within the third preset temperature range, maintain the oil pressure slope during the rapid filling phase and the buffer torque change phase; When the real-time hydraulic oil temperature is within the fourth preset temperature range, the oil pressure slope during the rapid filling phase is reduced and the oil pressure slope during the buffer torque change phase is increased. Wherein, the fourth preset temperature range is higher than the third preset temperature range, the third preset temperature range is higher than the second preset temperature range, and the second preset temperature range is higher than the first preset temperature range.

8. A controller, characterized in that, include: The memory is configured to store instructions; as well as The processor is configured to retrieve instructions from memory and, when executing the instructions, to implement the method of controlling gearbox shifting according to any one of claims 1 to 7.

9. A type of operating machinery, characterized in that, include: The controller according to claim 8; gearbox; The shift solenoid valve is used to control the gearbox to perform shift operations.

10. A machine-readable storage medium on which a program or instructions are stored, characterized in that, When the program or instructions are executed by the processor, they implement the method for controlling gearbox shifting according to any one of claims 1 to 7.

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