Optimal Design of Bipolar Power Pad for Dynamic Inductive EV Charging System Application

Abstract

This paper proposes a multi-objective design optimization of bipolar power pads (BPP) of dynamic inductive electric power transfer (IPT) with application in electric vehicles. Minimization of IPT's design cost, power loss, and maximization of the IPT system's tolerance against horizontal/vertical misalignment are considered as objective functions during optimization process. The proposed design variables of the proposed algorithm are the shield plate length and width, ferrite bar length and width, the overlapping length of the coils, the coil width and inner length of the coil. Power electronic limitations, maximum allowable electromagnetic field exposure, minimum efficiency (≤ 80%), and upper/lower limits of design parameters are considered as the constraints of this optimization problem. The time harmonic electromagnetic physics model of the BPP is analyzed using an FEMM software coupled with MATLAB. A Non-Dominated Genetic Algorithm (NSGA-II) is employed as the optimization method, in which, the electromagnetic magnetic measurements from the FEMM software is used to evaluate the fitness values of the proposed objectives. The proposed BPP design optimization is applied on a 10-kW IPT system as a case study. The optimization results produced 15 Pareto optimal solutions which allows the designer to select the best design parameters based on the objectives of highest priority. The experimental setup of the dynamic IPT system based on one of the Pareto solution parameters is constructed and illustrated with details.