Simulation of Secondary Controlled Hydrostatic Drive Train in Heavy Duty Vehicles

This paper addresses, the modeling and simulation of longitudinal vehicle dynamics of a heavy duty vehicleusing a typical hydrostatic drive train system. The Matlab- Simulink and Simscape platform is chosen todevelop the simulation program of the studied application, which is observed as the perfect rapidprototyping design tool achieving the desired objectives. In a HDT system, the displacement of its variabledisplacement hydro motor is often regulated by the swash plate angle using a hydraulic servo- mechanism. Therefore, the swash plate dynamics play an important role in the dynamics of the HDT system.In this paper, the tire and longitudinal vehicle dynamics and gasoline engine as a prime mover withtypical HDT and secondary control unit have been developed in Matlab- Simulink and Simscape environment.The secondary control unit is used to control hydro motor swash plate movements and consequentlythe motor instantaneous displacement, output shaft angular velocity and amount of entered torque to thetires. The investigation is performed studying the dynamical performance and behavior of the modelunder different input signals of secondary control unit.

Keywords:

Secondary control , Hydrostatic drive train (HDT) , Heavy duty vehicles , Simulation