Synthesis of a Cauer Equivalent Circuit for Electric Devices From Computed and Measured Data

This article proposes a method for modeling electric devices based on a Cauer circuit whose circuit parameters are directly determined from measured or computed data using the adjoint variable method. It has been shown that electric devices that are governed by the quasi-static Maxwell's equation can be modeled by the Cauer circuit. From the synthesized Cauer circuit, eddy current losses can be evaluated for a wide frequency range. Moreover, it can be embedded into a circuit simulator to perform the time-domain analysis. It is shown that the Cauer circuit whose parameters are identified using the proposed method works better for a simple numerical model than that whose parameters are identified using a genetic algorithm. Moreover, the Cauer equivalent circuit of a reactor and a power inductor is synthesized from the measured data using the proposed method. It is shown that the input impedance of the reactor and power inductor is well approximated by the Cauer circuit over the frequency domain of interest.