Abstract The mutual inductance between two coils is a key parameter in the design of inductive power transfer (IPT) system, and the effective calculation of mutual inductance is the theoretical foundation ofoptimizing IPT system structure and improving its transmission efficiency. In this paper, an analytical model of mutual inductance between two rectangular spiral coils is established by using second order vector potential (SOVP). The rectangular spiral coil is first simplified as a series of co-axial singlerectangular coils with rectangular cross-section. Thus, the magnetic field distribution of the rectangular spiral coil and its mutual inductance calculation are transformed into the superposition of the corresponding problems of multiple co-axial single rectangular coils. Then, the scalar potential of the primary singlerectangular coil is deduced based on the SOVP formulae, and the magnetic flux through the second rectangular coil is calculated accordingly. Finally, the analytic expression for mutual inductance of rectangular spiral coils with a double generalized integral term is derived. Two identical rectangular spiral coils are taken as an example for the verification of theoretical model additionally, and the calculated results are in good agreement with the experimental measurements. The proposed method can provide the basis for parameter optimization for the IPT systems using rectangular spiral coils as coupling devices.
WuDehui,HeTianfu,WangXiaohong等. Analytical Modeling and Analysis of Mutual Inductance Coupling of Rectangular Spiral Coils in Inductive Power Transfer[J]. Transactions of China Electrotechnical Society, 2018, 33(3): 680-688.
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2018, Vol. 33 
