Dynamic Modeling of Brake in Power-Split DHT and Pressure Tracking Control with Sliding Mode Variable Structure Method

Since the mode transition performance of power-split DHT (Dedicated Hybrid Transmission) are directly influenced by torque dynamic characteristic of the brake, the brake pressure should be controlled accurately. In this paper, a dynamic model of brake and its pressure regulating system are established by considering system nonlinear characteristics and input disturbances, and a sliding mode variable structure controller is developed to track the brake pressure. First, the operation principle of DHT’s pressure regulating system is introduced. Second, the dynamic models of solenoid proportional pressure valve, electromagnetic direction switching valve and brake are established with AMESim parametric plant model. Furthermore, a sliding mode variable structure controller for tracking pressure is designed based on MATLAB/Simulink. Finally, the AMESim parametric plant model is validated by measurements, and the proposed controller are verified by AMESim and Simulink co-simulation. The results show that the system dynamics can be well characterized by the AMESim parametric plant model. The target pressure can be tracked rapidly and accurately by using sliding mode variable structure controller and the controller has better robustness.