Multi-Interval Efficiency Design Optimization for Permanent Magnet Synchronous Generators Used in Hybrid Electric Special Vehicles

Abstract

This article presents a novel multi-interval efficiency optimization strategy to improve the overall driving cycle efficiency of permanent magnet synchronous generators for hybrid electric special vehicles. At first, the driving cycle rule of the hybrid electric special vehicles is investigated by mathematical statistics to fit the actual driving conditions. In addition, the multi-interval efficiency analytical model of permanent magnet generator is established for the most significant operating power intervals, i.e., 0-25%, 25-50%, 50-75%, and 75-100%. Then, the driving cycle efficiency is iteratively involved in the improved genetic algorithm program to obtain the optimized solution, which is also compared with the solution by the traditional rated efficiency optimization method to demonstrate the advantages of the proposed optimization method. Finally, the proposed optimal design is validated on a laboratory prototype of a 500-kW generation system under different load conditions.