Simulation And Experimental Study On Wheel Cylinder Pressure Estimation Model Of Automotive Electronic Stability System

The Electronic Stability Control(ESC)is an active safety system that integrates the three-part brake anti-lock brake(ABS),traction control system(TCS),and active yaw control system(AYC).The function of the ESC system is mainly achieved by actively adjusting the wheel-cylinder pressure and the engine torque.The wheel cylinder brake pressure adjustment is performed by a hydraulic actuator unit(HCU)and a control unit(ECU).The control accuracy of wheel cylinder pressure is related to the control effect of ESC system.Therefore,wheel cylinder pressure estimation has become an indispensable part of ESC algorithm.At the same time,to eliminate wheel cylinder pressure sensor and reduce ESC system cost,wheel cylinder pressure estimation model Become an economically suitable choice.The pressure model can be built as an independent control module independent of the ESC upper layer algorithm and used for new driving assistance functions of the car.Because ESC product technology has long been monopolized by foreign companies,the research on ESC by domestic car companies and universities mostly focuses on the development of system state recognition and upper control algorithms,while the research on the underlying control and the underlying executives is less.The wheel cylinder pressure estimation is studied.This paper adopts the combination of theoretical analysis,modeling and simulation and experimental verification.Firstly,it analyzes the hydraulic mechanism under different functions and different working conditions of ESC,analyzes the structure and working mechanism of key components of hydraulic actuator,and obtains ESC.The intrinsic flow relationship between the components of the hydraulic actuator unit under different working conditions.Secondly,the mathematical model of the key components of the hydraulic actuator is derived.The simulation model is built by simulink software platform to simulate the flow characteristics.Combined with the AMESim software platform,the joint simulation platform of the ESC hydraulic brake system is established and the flow characteristics are simulated and analyzed.The accuracy of the simulation model and the co-simulation platform.Finally,based on the flow characteristics and internal flow relationship of the ESC hydraulic actuator,the wheel cylinder pressure estimation model is established,and the accuracy of the model is verified by the experimental platform.