This approach automatically results in a current frequency twice as high as the chopper frequency so that the ripple of the phase currents is 22 kHz, i.e. it is outside of the audible range.

• 这种做法的结果会自动在一电流频率高一倍菜刀频率，使纹波的阶段，电流是22千赫，即是以外的发声范围。