This paper proposes a new control circuit to control the switching of the main switches of the used Zero Current Zero Voltage Transition (ZCZVT) inverter to ensure Zero Current and Zero Voltage Switching (ZCZVS). The reverse recovery losses of the main diodes are minimized and the auxiliary switches of the commutation cell are turned on at Zero Current Switching (ZCS) and off at ZCZVS. The commutation losses are practically reduced to zero due to ZCS. Sinusoidal Pulse Width Modulation (SPWM) is used to perform the switching of the power semiconductor devices and to control the output voltage value. MATLAB software is used to simulate the inverter circuit. Simulation results are presented to demonstrate the feasibility of the proposed control circuit.
Use of multilevel inverters is becoming popular in the recent years for high power applications. The important feature of these inverters is of having low harmonics content in the output voltage. The switching angles in a multilevel inverter are computed so as to produce an ac output voltage with minimum harmonics. A new control circuit is designed to achieve these angles. This control circuit has the ability to control the RMS output voltage using sinusoidal pulse width modulation (SPWM). The results presented in this work prove the ability of the designed control circuit to gain the required ac output voltage with minimum distortion.