Because the high-current, high-voltage devices are more used in railway locomotives, the four-quadrant rectifier units and the inverter units in traction converter both use IGBT component to continuously control the traction and braking. 由于铁路机乍中的大电流、高电压器件使用较多,牵引变流器中的四象限整流单元和逆变单元中都采用了IGBT元件,对牵引和制动实行连续控制。