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Design considerations for electromagnetic couplers in contactless power transmission systems for deep-sea applications


In underwater applications of contactless power transmission (CLPT) systems, high pressure and noncoaxial operations will change the parameters of electromagnetic (EM) couplers. As a result, the system will divert from its optimum performance. Using a reluctance modeling method, we investigated the gap effects on the EM coupler in deep-sea environment. Calculations and measurements were performed to analyze the influence of high pressure and noncoaxial alignments on the coupler. It was shown that it is useful to set a relatively large gap between cores to reduce the influence of pressure. Experiments were carried out to verify the transferring capacity of the designed coupler and system for a fixed frequency. The results showed that an EM coupler with a large gap can serve a stable and efficient power transmission for the CLPT system. The designed system can transfer more than 400 W electrical power with a 2-mm gap in the EM coupler, and the efficiency was up to 90% coaxially and 87% non-coaxially in 40 MPa salt water. Finally, a mechanical layout of a 400 W EM coupler for the underwater application in 4000-m deep sea was proposed.

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Correspondence to Ying Chen.

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Project supported by the National High-Tech R & D Program (863) of China (No. 2007AA091201), the Natural Science Foundation of Zhejiang Province, China (No. Y5090117), and the Qianjiang Excellence Project of Zhejiang Province, China (No. 2009R10036)

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Li, Zs., Li, Dj., Lin, L. et al. Design considerations for electromagnetic couplers in contactless power transmission systems for deep-sea applications. J. Zhejiang Univ. - Sci. C 11, 824–834 (2010).

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Key words

  • Contactless power transmission (CLPT)
  • EM coupler
  • Deep sea
  • Gap effects

CLC number

  • TM131.4+1