Evaluation on performances of a new three-phase five-level current source inverter

This paper presents a new three-phase five-level current source inverter. Each phase of this inverter operates separately so that it can work as a single inverter without change. Because a current zero in one phase doesn´t affect the others, this enables the implementation of a wide range of current PWM patterns for the reduction and selective elimination of output current harmonics. The extended sinusoidal PWM is applied to the new inverter, resulting in output current with very low distortion. Further, the AC output terminal capacitors are used to absorb overvoltage and filter the output PWM controlled current. As a result the output current of the inverter can trace different input reference waveforms. In addition, the inverter can drive loads varying in a wide range. Analysis and simulation results show that the proposed inverter is suitable for motor variable speed drives and current amplifiers