A NEAR SINUSOIDAL THREE PHASE FIVE LEVEL VOLTAGE SOURCE INVERTER WITH FUNDAMENTAL SWITCHING FREQUENCY

In this paper, a near sinusoidal three phase five level voltage source inverter with fundamental switching frequency is proposed. The proposed topology is constructed of 12 power switches and 12 diodes to achieve a three-phase five-level AC Y-connected output. The output line-to-line voltage is five levels and total harmonic distortion is lower. Multilevel inverters are used in the place where filters are not required and less harmonics are needed. Compared to the traditional three-phase inverters, the proposed three-phase five level inverter can achieve the five output voltage levels with fewer components. In this paper, the details of the mode analyses and control schemes are discussed. An experimental prototype with input voltage 500 V, output power 6 kW, THD 3.62%, and efficiency 98.40% is implemented to verify the theory and feasibility of the proposed topology.