中文摘要：

针对感应电能传输（inductive power transfer,IPT）系统多负载条件下能量传输效率问题研究频率与效率的关系,并从系统能量流动的角度解释效率特性。为了验证最大传输效率结论的正确性,采用双工作模式切换的电流调节方法和离散准滑模控制策略来维持原边谐振电流（激磁电流）的恒定。基于系统能量平衡函数关系,建立关于激磁电流峰值包络的系统离散变结构模型,构建具有重置积分环节的切换函数来改善系统的稳态响应。实验结果表明,当工作频率偏离副边固有谐振频率时,系统效率最大,合理的积分增益可以使系统具有较好的控制性能,对于负载大范围变化具有较强的鲁棒性,如当负载完全拿开时,控制器经过时长约为5 ms的调节,激磁电流最终稳定在参考值,表现出较好的抗扰动性,且系统效率均保持90%以上。

英文摘要：

Focusing on the efficiency problem of inductive power transfer（IPT） system with multiple loads,the methodology of the power-flow analysis was carried out to analyze the relationship between efficiency and frequency.In order to validate the conclusion and keep the stability and high efficiency of power transmission,the primary resonant current（exciting current） was regulated by switching between energy injection mode and free resonance mode,and a discrete-time quasi sliding mode control strategy was proposed.The variable structure model about the envelope of exciting current was constructed with energy equilibrium relations.Furthermore,a switching function was established with reset integral units to improve the steady state response.The results show that in the condition of multiple loads,the maximum efficiency can be achieved when operate frequency shifts away from the secondary inherent resonant frequency.The appropriate integrator gain can give the system good robustness when load changes in large scale.As the pick-ups are fetched away from the system completely,the exciting current returns to the reference value within 5 ms.Besides,the efficiency keeps a high level being above 90%.