五段式与七段式空间矢量脉宽调制下永磁同步电机高频噪声对比分析

为探明分别采用五段式与七段式空间矢量脉宽调制(SVPWM)的电动汽车驱动用永磁同步电机以载波频率为中心频率的阶次噪声差异,首先分析了永磁同步电机径向电磁力的时空特性,然后对径向电磁力进行仿真并对结果进行二维时空分解,最后对采用2种SVPWM控制的电机进行了振动噪声测试,识别出对电机高频噪声贡献较大的噪声阶次。通过对比发现,电机采用七段式SVPWM控制时,在转速530~9 000 r/min范围内0阶、8阶、-8阶噪声幅值分别降低21.21 dB(A)、9.21 dB(A)、12.65 dB(A),试验结果与理论、仿真结果的一致性较好。

Comparative Analysis of Permanent Magnet Synchronous Motor High Frequency Noise Under Five-Segment and Seven-Segment Space Vector Pulse Width Modulation Control

In order to figure out the difference of order noise with the carrier frequency as the center frequency of PMSM (Permanent Magnet Synchronous Motor) for electric vehicle driving with five-segment and seven-segment SVPWM (Space Vector Pulse Width Modulation) techniques respectively, firstly, the time- space characteristics of the radial electromagnetic force of PMSM are analyzed. Then, the radial electromagnetic force is simulated and the results are decomposed in time and space. Finally, vibration and noise tests of the motor driving with two kinds of SVPWM techniques are carried, respectively. The electromagnetic noise order contributed significantly to the motor high frequency noise is identified. Compared with five-segment SVPWM, it is found that the amplitude of the 0th, 8th,-8th order noise decreases by 21.21 dB(A), 9.21 dB(A) and 12.65 dB(A) in the range of 530~9 000 r/min when the motor is driven by seven-segment SVPWM. The test results are in good agreement with theory and simulation results.