An Accurate High-Speed Method for Mutual Inductance Calculations of Coplanar Disk Coils Using Generalized Hypergeometric Functions
Keywords:
Disk coils, generalized hypergeometric function, modified Bessel functions, mutual inductanceAbstract
Traditional method using integral of the Bessel and Struve functions is not suitable for calculating the mutual inductance between two coplanar disk coils. Considering the monotonicity of modified Bessel and Struve functions, an alternative method using these monotonic functions is applied to calculate the mutual inductance, and numerical evaluations can be accelerated considerably. Series solutions using the generalized hypergeometric functions are further obtained by solving the infinite integrations, and these series are compared with the aforementioned integral methods. The numerical results show that the series solutions are much more faster than the integral ones, and with the series method, results of very high accuracy can be obtained within a small fraction of one second in most cases. Furthermore, we point out and prove the existence of the decoupling positions at which the mutual inductance will vanish.
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