Research On Pressure Control Method Of Vehicle Electronic Stability System

The electronic stability system is one of the key components of the vehicle active safety control system.The wheel cylinder pressure control algorithm is between the master control algorithm and the underlying hardware driver in the stability control algorithm,the pressure control accuracy directly affects the vehicle stability control effect.Therefore,in order to improve the accuracy of brake pressure control,to ensure the performance of ESC system,to reduce production costs and to improve the competitiveness of independent products,this article relies on needs of the National 863 special projects,special international cooperation projects;Continental Aotumotive Corporation’s internal technical information and sample,to carry out related research of the brake pressure control algorithm.The main contents of the paper include the following four parts:1.Mechanism analysis of hydraulic adjustment unit.Based on the physical structure inside the hydraulic adjustment unit,the components of the hydraulic condition unit and their interconnection relationship are clarified.Under the control of active pressure and passive pressure,the control of pressurization,pressure reduction,pressure maintaining and different working conditions of the braking system is studied.2.Analysis of working mechanism of hydraulic actuator.Make Physical analysis of ESC hydraulic adjustment unit key components,analyse the working principle at the same time and do the test validation,provide preliminary preparation for the development of pressure control algorithms.3.Research on Braking Pressure Control Algorithm.Based on the study of the characteristics of the previous parts,the control requirements of the step pressure and the linear pressure control algorithm are analyzed theoretically.The active pressure control method is simulated and the key control variables in the pressure control algorithm are obtained by experiment calibration,the pressure control method for engineering practice is found out.4.Test validation.Micro-Autobox was used as the controller,and the braking system with hydraulic adjustment unit was selected to build a hardware-in-the-loop simulation platform.The pressure control algorithm was tested for pressure change in different states.Through the above research work,we have the following conclusions:1.Analysing the mechanism of hydraulic adjustment unit components and using the component characteristics test to verify can provide theoretical and experimental guidance for the development of pressure control algorithms;2.The key variables of pressure control are obtained,and the method of calibration variable calibration is given.The pressure control algorithm can be developed in the process of engineering practice and the algorithm is well transplanted.3.The bench test shows that the pressure control algorithm can be used in the process of active pressure regulation and passive pressure regulation to make the actual pressure of the wheel cylinder follow the demand of the target wheel cylinder pressure,and the control precision is high,which provides the implementation of the vehicle stability control algorithm with strong protection.