针对一种π型谐振网络的非线性感应电能传输系统(IPT),应用广义状态空间平均(GSSA)法对时域状态变量进行频域分解,并用低阶傅里叶系数的实部和虚部作为新变量将其近似成一个线性时不变系统.为对负载输出电压进行无静差跟踪控制及鲁棒性能分析,综合考虑系统的中低频参数摄动及高频未建模部分的不确定性,通过在频域上调整选择多目标优化的加权函数,设计出基于混合灵敏度的H∞输出反馈鲁棒控制器.仿真结果表明,在鲁棒控制作用下,闭环系统传递函数的H∞范数达到了小于1的性能指标,当发生负载参数摄动及输入电压干扰时,实现了对负载输出电压的无静差鲁棒跟踪.实验结果亦证明,该方案是可行的.
By taking a nonlinear inductive power transfer(IPT) system with π-type resonant network as the research object,this paper applies the generalized state-space averaging(GSSA) method to the frequency domain resolving of time-domain state variables,and takes the real and imaginary parts of low-order Fourier coefficients as new variables to approximately build up a linear time-invariant system.Moreover,in order to implement the tracking control without steady-state error and the robustness analysis of the load output voltage,the parameter perturbation in medium-and low-frequency domains as well as the uncertainty of un-modeling part in high-frequency domain are comprehensively considered,and an mixed-sensitivity output-feedback H∞ robust controller is designed by adjusting the weighting functions for multi-objective optimization in the frequency domain.Simulated results show that,with the proposed robust controller,the H∞ norm of the transfer function of the closed-loop system reaches the perfor-mance index less than 1;and that the robust tracking control without steady-state error can be successfully realized for the load output voltage in the presence of load parameter perturbation and input voltage disturbance.Experimental results indicate that the proposed controller is feasible.