关键词: 六相电机；电磁力；NVH；模态

Abstract: In order to study the problem of radiated noise of vehicle six-phase motor, this paper takes a certain electric drive assembly as the research object, tests and analyzes its noise, vibration and harshness (NVH) performance on end of line (EOL) bench. Test results show that the 48th order noise of the motor exceeds the target in the frequency band range of 988～1 325 Hz and 1 966～2 200 Hz, and the maximum excess scalar is about 7 dB. Then, using the method of combining theoretical analysis and simulation, it is concluded that the cause of the noise problem is that the radial electromagnetic force of the 12th order of the electrical frequency is too large, which provokes the structural mode of the 1 121 Hz and 2 023 Hz systems, and the stator vibration is caused by the noise radiated from the oil pan after the structure is amplified. In order to solve the problem of large radial electromagnetic force, this paper adopts an evolutionary algorithm to weaken the radial electromagnetic force of the 12th order harmonic of the 0th order time in space by using the rotor opening auxiliary slot and scheme. At the same time, the modal mode amplitude is reduced by optimizing the oil pan structure. Finally, the NVH performance of the motor is verified by simulation method, and the effectiveness of the scheme is verified.

Key words: Six-phase motor; Electromagnetic force; NVH; Mode