ANALYTICAL CALCULATION, SIMULATION CALCULATION AND EXPERIMENT OF EDDY CURRENT LOSS OF SINGLE-CORE AND MULTI-CORE COILS

As an important internal structure of a super magnetostrictive transducer, the resistance loss caused by the eddy current effect in the working state of multi-coil cannot be ignored. The mechanism of eddy current loss of single-core and multi-core coils is not the same. The resistance loss of single-core coils is mainly dominated by the skin effect, while the resistance loss of multi-core coils is influenced by both the skin effect and the proximity effect. In this paper, based on Maxwell's equations and eddy current effect, the analytical calculation formula of the resistance loss of single-core and multi-core coils is derived, and the finite element method is used to study the loss of single-core and multi-core coils under different ultrasonic frequency bands under the same current and the same cross-sectional area, and finally based on the principle of pure resistance of the circuit in the resonant state of RLC series circuit, the AC resistance of single-core and multi-core coils is measured, and the eddy current loss of the coil is obtained by combining the calculation formula of the loss power. The experimental results are consistent with the simulation results and analytical calculation results, verifying the effectiveness of the analytical calculation formula and experimental method for coil power loss.