Event-Based <i>H<sub>∞</sub> </i> Tracking Control for the T-S Fuzzy-Based SP-IPT System With Coil Misalignment
Shuangxin Zhu, Yu Huang, Engang Tian, Yuqiang Luo, Xiangpeng Xie, Hongtian Chen
Abstract
This paper investigates the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${H}_{\infty}$</tex-math> </inline-formula> tracking control problem for the series-parallel (SP)-inductive power transfer (IPT) system with coil misalignment. To describe the nonlinear characteristic caused by large-scale coil misalignment, a Takagi-Sugeno (T-S) fuzzy modeling approach is successfully applied to the SP-IPT system. By introducing an integrator related to the error between the actual and the reference system output signals, an augmented T-S fuzzy-based SP-IPT system model is established. Then an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${H}_{\infty}$</tex-math> </inline-formula> parallel distributed compensation (PDC) fuzzy control strategy with a valid event-triggering scheme (ETS) is put forward to guarantee desired tracking control performance and decrease unnecessary packet transmission at the same time. To ensure the asymptotic stability of the augmented T-S fuzzy-based SP-IPT system and the disturbance suppression index, sufficient conditions are employed by utilizing an extended Lyapunov functional method. Finally, a simulation example with regard to the SP-IPT system is developed, which demonstrates that the event-based <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${H}_{\infty}$</tex-math> </inline-formula> PDC fuzzy control strategy proposed in this paper can maintain the constant output voltage of the SP-IPT system while saving communication resources. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —For IPTs, the coil misalignment phenomenon unavoidably affects their desired performance, such as constant voltage and current output, constant power output, maximum efficiency tracking, and so on. Therefore, the corresponding tracking controllers have brought wide attention in the power transmission research. The proposed control strategies have been utilized to suppress the negative influence caused by coil misalignment, whereas it is difficult for these strategies to ensure the robustness and the stabilization under large-scale coil misalignment. To deal with this problem, this paper is devoted to design a T-S fuzzy-based <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${H}_{\infty}$</tex-math> </inline-formula> control strategy with an ETS to guarantee the stabilization of practical inductive power transfer systems. It is worth mentioning that the proposed robust control strategy is proposed based on the IPT system with T-S fuzzy rules and the ETS, which can simultaneously guarantee desired tracking control performance and decrease unnecessary packet transmission in real applications. In this paper, only constant voltage tracking control are considered for the IPT system with coil misalignment, but some other tracking performance still need to be researched in practice. Therefore, we will take the tracking performance indexes of constant current and constant power into account in the future research.