关键词: 电液位置伺服系统, 连续摩擦模型, 建模不确定性, 非线性控制

Abstract:

Electro-hydraulic positioning servo system is a complicate nonlinear control plant,and usually suffers various modeling uncertainties,which make it more difficult of the high performance controllers design to meet the servo accuracy requirements.To overcome the above problem,a nonlinear mathematics model was established.Meanwhile,a new control method,named as an integral robust of the sign of the error,was also designed based on Lyapunov stability theory.The output tracking error was guaranteed to converge to an arbitrary small neighborhood around zero.Simulation results show that this control strategy can effectively attenuate the adverse effect brought by the modeling uncertainties and apparently improve the tracking accuracy.In addition,the achieved control input is continuous, which is more suitable for implementation in practice.

Key words: electro-hydraulic positioning servo system, continuous friction model, modeling uncertainties, nonlinear control