Research On Multi-motor Coordinated Control System Of Road-rail Vehicle

Currently,with the rapid increase in the operating mileage of high-speed railway and subway vehicles,the issue of rail vehicle service guarantee has received widespread attention from all walks of life in the community.The traditional shunting operations which mainly based on shunting locomotive traction is inflexible.The large amount of exhaust gas emitted by diesel Road-rail vehicle has a certain impact on the environment.The electric Road-rail vehicles can flexibly complete the unpowered traction of the vehicles,and avoid the environmental damage caused by the Road-rail vehicles.It is one of the development directions of the rail service guarantee vehicles in the future.The requirements of mobility make it possible to implement in-situ steering,diagonal driving and other operating modes in a small space for pure electric bus and railway vehicles.If high-precision control cannot be achieved,it will be difficult to control the steering center at one point,which is extremely prone to roll.Therefore,the problem of multi-motor cooperative control of pure electric road-rail vehicles needs to be solved urgently.The main research works are as follows:Firstly,takes the electric 4D4 S road-rail vehicles as the research object,analyzes its working principle and vehicle characteristics,designs the electric control system,and constructs the mathematics of the permanent magnet synchronous motor and the kinematic equations of the steering system.For the synchronous control of multiple motors,the traditional PID control algorithm has a strong applicability to charged objects which is suitable for most control occasions.However,the dynamic characteristics and steady-state accuracy of the coupled structure cannot meet the requirements.In order to solve the above problems,this paper builds an improved deviation coupling control structure to stabilize multi-motor cooperative control system by designing a rotary angle co-compensator.but it is fail to improve the control accuracy and dynamic characteristics of the system,so the intelligent control algorithm is introduced.PID control algorithm has good steady-state performance.Fuzzy PID control algorithm has fast response.In order to solve the defect that the fuzzy PID algorithm has limited steadystate accuracy in high-precision control,this paper proposes a non-singular fast terminal sliding mode control algorithm based on corner control to reduce the system error,and introduces a super-twist algorithm to solve the problem of chattering.Aiming at the three types of control algorithms researched above,the multi-motor cooperative control model is simulated through the MATLAB / Simulink software.And consequents show that the three control algorithms can accomplish the multi-motor cooperative control well.And the super-twisted non-singular sliding mode control algorithm is better than the other two algorithms in control accuracy,dynamic characteristics and signal response following performance.Finally,the algorithm was applied to the road-rail vehicle and a series of tests were carried out.The test analysis results show that the road-rail vehicle designed in this study can achieve the required steering,diagonal driving and in-situ rotation driving.At the same time,the supertwisting non-singular sliding mode control algorithm can well realize the coordinated control of multiple motors in the steering system,and improve the response speed and steady-state characteristics of the system.This article can lay the foundation for the in-depth study of the control strategy of the pure electric road-rail vehicle steering system and other multi-axis cooperative control systems.