Design and Optimization of Electromagnetic Structures for Linear ISG Used in Range-Extended Electric Vehicle

According to the operating requirements of the linear range-extender used in range-extended electric vehicle, as well as structures and performances of the self-developed linear engine, a tubular permanent magnet (PM) linear ISG is designed. The impact of varying electromagnetic structure on the performance is studied by finite element analysis (FEA) in electromagnetic field. On that basis, optimum structural parameters for the linear ISG are determined using multi-objective optimization. The results show that the self-designed linear ISG can meet the performance requirements. After optimization, the output power increases 8.7 percent; the no-load induced electromotive force increases 12.1 percent; the standard deviation of detent force shows a 94.6 percent reduction; the efficiency basically remains constant.