基于GFRF的二次调节流量耦联系统的频域非线性H∞控制

Nonlinear H-infinity control of flow-coupled system with secondary regulation using GFRF in frequency domain

二次调节流量耦联系统为非线性系统,在Volterra级数描述该系统的基础上,通过SISO多项式类非线性系统的GFRF递推算式获得二次调节流量耦联系统的广义频率响应函数GFRF(generalized frequency response function).基于系统的GFRF,在频域内应用非线性控制理论为系统设计了镇定控制器和非线性H∞控制器,不仅使系统稳定,而且能达到无超调、无稳态误差.此外,在白噪声条件下证明该控制器比线性控制器抗干扰性强.

The flow-coupled system with secondary regulation was a nonlinear system. Its generalized frequency response function （GFRF） was obtained through the iterative method of SISO system using Volterra series. On the basis of GFRF, the stabilized controller and the nonlinear H-infinity controller were designed by nonlinear control theory in frequency domain. The simulation results show that the system becomes stable after a linear controller was added. The nonlinear H-infinity controllers eliminate the system steady error and overshoot. They are working better in rejecting white noise disturbances than the linear H-infinity controller.