Research on Micro-torque Passive Motor-driven Load Simulator based on Backstepping Theory

A micro torque high-frequency high-precision passive electric load simulation system is researched,the paper proposes a backstepping control method to solve the strong force/position coupling problem.The system is seen as a single-input and multiple-output system,and a dynamic model of the coupling is established.By introducing an appropriate virtual control quantity,this paper designs a backstepping controller,which makes the system error have an expected progressive shape,and theoretically proves the system stability on the base of Lyapunov method.From the simulation results,a conclusion could be drawn that when the sine signal is up to 60 Hz,amplitude tracking error of bearing system is about 0.5‰ rad and phase lag is about 10°;At the same time,the amplitude tracking error of loading system is about 0.2%N·m and phase lag is about 10°.Therefore,the simulation results validate this method and prove the feasibility of this method.