Frequency Sensitivity Analysis of Eddy Current system in Voltage Source Problems

This paper proposes a high-order frequency-sensitivity analysis of a linear eddy-current system coupled with voltage-driven circuit and shows its validity through two numerical examples. In this field-circuit coupled system, an exciting coil is connected to a voltage source and an external circuit in series. An analytic sensitivity formula for the sensitivity analysis is derived by differentiating the variational equation of the coupled system with respect to frequency. An nth order frequency sensitivity is obtained from the lower-order one. The numerical analysis of the frequency-sensitivity is performed using a commercial finite-element analysis software. A cylindrical wire and an induction heating system are numerically tested to validate the frequency-sensitivity analysis.