CIRCUIT AND METHOD FOR DECOUPLING THE OSCILLATING POWER FOR SINGLE-PHASE INVERTERS

摘要

The invention relates to a circuit and method for decoupling the oscillating power for single-phase inverters in order to cancel the alternating component of the current on the direct current line of the inverter. The claimed circuit comprises an H-bridge inverter (), supplied with a DC voltage (), the bridge having four pulse width modulated (PWM) transistors, the median points of the two arms of the inverter bridge being connected to two filtering coils () and two alternating current non-polarized capacitors () being connected to the output terminals of the coils, the capacitors being meant to decouple the oscillating component of the power, the other two terminals of the capacitors being together connected to one of the DC terminals () of the inverter. The claimed method consists in controlling the inverter arms with the purpose of generating two voltages which contain harmonics of even order for transferring the oscillating power towards the decoupling circuit, so that the DC current line of the inverter contains only the average component of the power, and the voltage and the current at the output terminals () are not affected.