Optimal Frequency Design Method of IPT System Based on Power Loss Model for Rail Transit

Recently, inductive power transfer (IPT) system has developed rapidly. However, there is currently no optimal frequency design method for IPT system applied in rail transit, lacking theoretical and practical support based on systematic in-depth research. Therefore, this paper proposes an optimal frequency design method for IPT system applied in rail transit. The optimal frequency is determined by establishing the power loss model of the IPT system. Based on theoretical analysis, this paper offers guidelines in selecting the optimum frequency. A 30 kW IPT system prototype for maglev train is built to confirm the theoretical results. It is concluded that when the length of the transmitting coil is 5 m, the efficiency of the IPT system is the highest for the operating frequency of 29.1 kHz.