Improved Trans-Z-Source Multi-level Inverter with Continuous Input Current for Induction Motor Drives

This paper presents an improved trans-Z-source network for multilevel voltage source inverters (VSI). A coupled inductor is used in the impedance network for voltage boosting. It has continuous input current and high boost factor. Proposed topology has got three degrees of freedom. Wide range of output voltage can be obtained by adjusting the turn ratio of the coupled inductor or by varying the shoot-through time period or the modulation index. This circuit operates with good performance for entire power factor loads. Modulation technique used is simple boost control with space vector PWM. Performance of the proposed topology is validated using MATLAB simulation on a 3HP, 220V scalar controlled three-phase IM drive.