FIVE-LEVEL POWER CONVERTER, CONTROLLING METHOD AND CONTROLLING DEVICE THEREOF

摘要

The present invention provides a five-level power converter and its controlling method. The five-level power converter comprises an inverter and at least one rectifier. Said rectifier comprises at least one rectify-controlling circuit and four capacitors each two of which are connected in parallel. Each first end of the first capacitor to the fourth capacitor is connected together to GND. Said rectify-controlling circuit is used to input current to each second end of the first capacitor to the fourth capacitor respectively, wherein the polarity of electric charge accumulated on the second end of the first capacitor and the second end of the second capacitor is opposite to the polarity of electric charge accumulated on the second end of the third capacitor and the second end of the fourth capacitor. Said inverter comprises a discharge-controlling circuit, and a series-connected first inductance unit and first load. The discharge-controlling circuit is used to discharge from the second ends of the four capacitors of the rectifier sequentially. The discharge current floats to the series-connected first inductance unit and first load. The charging and discharging to each capacitor of the four capacitors are staggered.