Design And Control Of Multi-plate Clutch Pump-control Hydraulic Actuator System

The automatic clutch actuator system is an important part of automatic mechanical transmission and considerably influences vehicle performance,including such aspects as safety,comfort,drivability,reliability,and shifting quality.In order to cope with the highly competitive market environment and make the automotive drive system integrated,lightweight,and meet the requirements of high efficiency and low cost.This paper proposes an integrated design and optimization scheme of a pump-controlled direct-drive actuator system for multi-plate clutches,and performs fluid-hydraulic control based on system characteristics.The multi-disc clutch pump-controlled hydraulic actuator system consists of a brushed DC motor,an external gear pump,and a hydraulic release bearing.The system uses the speed of the motor to change the output fluid flow rate of the pump,which directly drives the hydraulic separation bearing,to control the fluid pressure that drives the clutch.The system eliminates expensive solenoid valve components and avoids the processing of complex oil circuit panels;The system adopts a pressure source direct-drive structure to drive the multi-plate clutch,which not only retains the advantages of high power output of hydraulic actuators,but also ensures small energy loss and layout volume while ensuring effective torque transmission,which is suitable for the trend of vehicle miniaturization and integration.At the same time,using pressure control instead of displacement control of the actuator can ensure that the clutch can complete effective torque transmission.This article focuses on the design and control of multi-plate clutch pump-controlled hydraulic actuators.The main research contents are as follows:1.According to the working principle and torque transmission characteristics of the multi-plate clutch,the design requirements of the actuator system are clarified.Next,this article introduces the working principle and characteristic advantages of the pump-controlled direct-drive clutch actuator,and proposes an improved solution for multi-plate clutch fluid pressure control in view of the shortcomings of the original single-plate clutch actuator and position control.2.According to the design scheme and system structure,the required pressure and fluid flow are determined,and the characteristics of the hydraulic fluid and the nonlinear load force in the actuator system are analyzed;Combining the mathematical model and characteristic analysis results of the components,a simplified control-oriented system model is derived.3.From the perspective of nonlinear control methods,combining the respective advantages of "model theory" and "control theory",considering the nonlinearity,time delay and disturbance uncertainty of the system,a feedforward-feedback adaptive controller based on RBF NN approximation is proposed,the controller structure and update mechanism were analyzed in detail.Based on the structure,the advantages of the controller are explained,and the robustness of the system is analyzed theoretically.4.Based on the physical model,combined with the design needs and system characteristics,the related components were selected and designed,the experimental bench was completed;Based on the rapid control prototyping environment and simulation model,the actual bench and simulation model of the actuator were tested in open loop to verify the fidelity of the model;Based on the high-fidelity simulation model obtained in the open-loop test,response tracking simulation tests under various operating conditions were performed to verify the control effect and robustness of the proposed controller.Finally,the pump control actuator system design and hydraulic control work are summarized,and the conclusion is drawn that the control algorithm can fulfill the control goals that meet the daily clutch operation requirements,and has a strong ability to adapt to fluid uncertainty under a small calibration.