Design method of direct-current side capacitor capacitance value of T-type three-level converter

The invention relates to a design method of a direct-current side capacitor capacitance value of a T-type three-level converter. According to the fluctuation condition of the maximum neutral-point voltage, the capacitor capacitance value of the direct-current side is determined. In consideration of open-circuit fault of a switching device, firstly, a bridge arm with the open-circuit fault of the T-type three-level converter is distinguished; next, the driving signals of all switch devices on the open-circuit fault bridge arm are closed, the maximum neutral-point voltage fluctuation coefficientis determined on the basis; and finally the capacitor capacitance value of the direct-current side is obtained. According to the design method, a direct-current side electrolytic capacitor with a relatively large capacitance value can be replaced by a thin-film capacitor with a relatively small capacitance value, so that the cost is lowered, the size is reduced, and the power density is enhanced. 本发明涉及一种T型三电平变流器直流侧电容容值的设