Robust Control of IPT System for Constant Current Charging under Multiple Parameter Perturbations

This article proposes a μ-controller based on the structured singular value with regard to the uncertainty of multiple parameter perturbations and external disturbances of inductive power transfer (IPT) systems to achieve constant current charging. By using a boost converter as an impedance compensation network, the IPT system can obtain the maximum power transfer efficiency when the charging starts. However, the charging current varies under the load and frequency perturbation during the charging process. This article presents a controller that ensures constant current charging and robust operations. A generalized state-space averaging is established, and a standard M-Δ configuration by separating the uncertain parameters and a μ-controller are proposed to form a closed-loop control system. The simulation and experimental results show that the proposed control method has strong robustness against load and frequency perturbation and also has a certain ability to suppress other external disturbances.