Wireless power transfer to moving objects realized by parity-time symmetry

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04036
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21010:Power engineering-related
• Research Institution: Okayama University of Science
• Principal Investigator: Ishida Hiroki 岡山理科大学, 理学部, 教授 (50413761)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: ワイヤレス給電 / 空間・時間反転対称性 / ロバスト性

Outline of Final Research Achievements

By incorporating Parity-Time (PT) symmetry into magnetic resonance-based wireless power transfer, we developed a system that enables stable wireless power transfer even when the position of the coils varies. In this study, we explored a system configuration that can preserve PT symmetry over a wide range of distances (transmission distance) between the power transmission coil and the power reception coil, misalignment between coils, and changes in the orientation of the coils. This was done using theoretical analysis and computer simulations.
As a result of the research, we succeeded in improving the transmission distance and tolerance to coil misalignment to approximately double that before the start of the research. This was achieved through the optimization of coil shapes, a resonant circuit topology suitable for PT symmetry, and the adjustment of apparent load resistance using a DC-DC converter.

Free Research Field

ワイヤレス給電

Academic Significance and Societal Importance of the Research Achievements

空間・時間反転（PT）対称性を応用したワイヤレス給電の研究は、米国や中国で盛んに行われているが、日本国内では研究が行われていない現状があった。本研究課題では、単に動作原理の理解だけに留まらず、この分野の発展に繋がる幾つかの知見を見出すことができた。また、理論解析のみに留まらず、理論解析結果に基づきシステム（実機）の開発も行った。開発したシステムは、理論予測通りの電力伝送性能を有していることを確認した。また、本システムは製造コストや動作安定性からも、実用性が高いことが確認された。現在、民間企業と共同で実用化を目指し開発を進めており、更なる発展が期待できる。