Fast Evaluation of Driving Cycle Efficiency of Interior Permanent Magnet Synchronous Machines for Electric Vehicles Considering Step-Skewing

In this paper, a fast evaluation of efficiency map and driving cycle efficiency of interior permanent magnet synchronous machines (IPMSMs) for electric vehicles (EVs) is proposed. Several techniques are applied to speed up the simulation process, including the iron loss and AC copper loss calculations via static and time-harmonic magnetic simulation, efficiency map buildup via surface-fit and driving cycle efficiency via finite element interpolation. Furthermore, an equivalent phase current advance angle technique is used to imitate the step-skewing simulation. As a result, compared to the commercial software, the calculation time consumption of the efficiency map and driving cycle efficiency can be reduced by 99.3% and 98.1%, respectively. It shows a great potential for the fast evaluation of the IPMSMs performance. Finally, this fast calculation method is combined with differential evolution algorithm to carry out a multi-mode and multi-objective optimization of an IPMSM. It will be of great beneficial for the determination of the optimal traction motors for EVs.