Search International and National Patent Collections

1. (WO2018098975) PULSE WIDTH MODULATION METHOD, PULSE WIDTH MODULATION SYSTEM, AND CONTROLLER

Pub. No.:    WO/2018/098975    International Application No.:    PCT/CN2017/081600
Publication Date: Fri Jun 08 01:59:59 CEST 2018 International Filing Date: Tue Apr 25 01:59:59 CEST 2017
IPC: H02M 7/537
H02M 1/12
Applicants: HUAWEI TECHNOLOGIES CO., LTD.
华为技术有限公司
Inventors: LIU, Fangcheng
刘方诚
XIN, Kai
辛凯
GUO, Haibin
郭海滨
Title: PULSE WIDTH MODULATION METHOD, PULSE WIDTH MODULATION SYSTEM, AND CONTROLLER
Abstract:
A pulse width modulation method, a pulse width modulation system, and a controller. According to the present application, the rate of change of a common-mode component of a three-phase inverter is changed as the degree of modulation of the inverter is changed, so that the stability and harmonic characteristics of the three-phase inverter are improved, and flexible adaptive adjustment is implemented. The pulse width modulation method comprises: obtaining an initial three-phase modulation wave and a degree of modulation of an inverter (601); calculating an adjustment coefficient of the rate of change of a common-mode component according to preset modulation parameters and the degree of modulation of the inverter; calculating a modulation wave set corresponding to the initial three-phase modulation wave according to a preset maximum modulation wave amplitude limiting value, a minimum modulation wave amplitude limiting value, the initial three-phase modulation wave, and the adjustment coefficient of the rate of change of the common-mode component, and selecting, from the modulation wave set, a modulation wave with a minimum absolute value as a common-mode modulation wave (603); and performing waveform superimposition on the initial three-phase modulation wave and the common-mode modulation wave to obtain a three-phase output modulation wave.