Misalignment Tolerance Extension for Inductive Power Transfer System by Utilizing Slight Frequency-detuned Compensation

• Published in: IEEE transactions on transportation electrification p. 1
• Main Authors: Chen, Chen, Jiang, C. Q., Ma, Tianlu, Wang, Xiaosheng, Fan, Yuanshuang, Xiang, Jingchun
• Format: Journal Article
• Language: English
• Published: IEEE 2024
• Subjects: Coils; Couplers; Couplings; Fluctuations; Inductive power transfer (IPT); misalignment; power fluctuation; Resonant frequency; slight frequency detuned; Switches; Topology; topology switch
• ISSN: 2332-7782; 2332-7782
• DOI: 10.1109/TTE.2024.3385831

For inductive power transfer (IPT), inevitable coupling variations caused by physical misalignments will bring large output power fluctuation. This paper investigates and analyzes the new transmission characteristics of slight frequency-detuned LCC-S and S-S compensation topologies. A misalignment extension approach is proposed by combining two detuned topologies to achieve relatively constant output power over a wide misalignment range. Firstly, the mathematical models of two detuned topologies are derived considering the imaginary part of the impedance. Then, the transmission characteristics of the detuned and resonant situations are compared by numerical simulation. Meanwhile, a detailed switch strategy based on DC current detection is analyzed and implemented to realize the offset degree recognition and topology switch. Finally, a 200 W IPT platform is fabricated to verify the correctness of the theoretical analysis and the feasibility of the proposed method. Experimental results show that the maximum output power fluctuation is only 2.96% when the coupling coefficient changes by 64.6% from 0.254 to 0.09. Compared with existing works, the proposed method can improve the misalignment tolerance and eliminate complicated coil designs and dual-side controls.