Multipulse AC-DC Conversion Fed 3rd Harmonic Injection Based SPWM Controlled Cascaded MLI Driven VCIMD

This paper present a 36-pulse AC-DC converter fed 5-level cascaded multilevel inverter (MLI) driven vector controlled induction motor drive (VCIMD). A modular transformer is utilized to make the grid current nearly sinusoidal and the transformer is connected to achieve a 36pulse AC-DC converter. A symmetrical 5-level cascaded MLI is utilized on the motor side, which offers the good performances of the proposed VCIMD. A 3$^{rd}$ harmonics injection based sinusoidal pulse width modulation (SPWM) is proposed in this paper, for variable speed induction motor drive to achieve the performances similar to space vector modulation (SVM). A 5level cascaded MLI has less switching loss. It is because, it is operated at low switching frequency. The Simulink/MATLAB base simulations results are verified by the experimental results and both the simulation and experimental results are given in this paper.