电液伺服系统的逆向递推鲁棒自适应控制

Backstepping robust adaptive control for an electro-hydraulic servo system

针对电液伺服系统存在的非线性特性、参数不确定性,且不确定性不满足匹配条件,引入虚拟控制量的概念,提出了一种逆向递推鲁棒自适应控制方法。该方法把整个系统分成了一个二阶和一个一阶两个子系统,对其进行递推式的分步自适应控制,从而简化了控制器的设计,使计算量大为减少;利用参数自适应和鲁棒控制相结合的方法,使控制器具有较强的抗干扰性。仿真结果显示,该控制方法具有较强的鲁棒性及良好的跟踪性能,与采用 PID 的控制方法相比,系统具有更好的控制性能及更强的抗干扰性。

Since the dynamics of electro-hydraulic system are highly nonlinear and have large extent of model uncertainties including big changes of load and hydraulic parameters, moreover these uncertainties are unmatched, a backstepping robust adaptive control approach is proposed via introducing a virtual control concept . The control approach makes the system into a second-order subsystems and a first-order subsystem, and then uses a backstepping adaptive method to control the subsystem, thus the controller is simplified and the calculating amount is reduced to a great extent. The parameter adaptive control is combined with robust control to make the system remain insensitive to parameter uncertainties and disturbances. Simulation results indicate that the proposed approach improves position tracking accuracy considerably and is more robust compared with PID control.