Electrical Power Steering System Control Strategy And Experimental Research

Along with development of national economy, auto industry as the pillar industry of national economy, play an important role in national economy and social development, steering stability, driving safety and driving comfortability has always been a focus of the auto industry. Steering system as an important device to maintain or change the direction of the vehicle, to ensure that the vehicle safety and improve the pilot operation. The application of power steering technology can greatly lighten the working strength of drivers. The electrical power steering system as one of the advanced vehicle power steering system, the design of the control strategy has become the key technology. Electrical power steering system as the research object, main work includes the following aspects:Based on the dynamics analysis of EPS, we use MATLAB/Simulink and CarSim software platform respectively to build the model of EPS, the steering resistance moment model and the vehicle model, and build the interface of co-simulation. Though analyze the relationships between steering portability and road sense, we set up the characteristics curve of EPS. Using the real vehicle experiment results, the applicability and accuracy of identification of electric power steering system was verified based on the recursive least squares identification method parameter identification to EPS.Aiming at solving the road random disturbance and sensor noise problems in EPS, the stability of EPS was analysised by designing the system of linear quadratic gaussian type optimal control system and control strategy combined with loop back feedback technology. The vehicle handling stability and the return-to-center performance were analysised and the model predictive control strategy for EPS was desined based on the model predictive control theory. On the base of combined simulation model, the simulation experiment for the control strategy of EPS was carried out. The result exhibited that the EPS control strategy is effective and feasible, which could improve the turn portability and handling stability of the vehicle.The rapid control prototype of EPS based on the MATLAB/Simulink software platform and the test vehicle equipped with EPS was researched. The actual control effect of the control strategy was verified. The experimental results showed that the designed control strategy can effectively improve the steering portability, vehicle handling stability and return-to-center performance.