Sensor-less Drive of Induction Motor Based on A New Hybrid Cascaded Multilevel Inverter

Power electronic inverters are becoming more and more popular for various industrial drive applications. Many kinds of multilevel inverter topologies have been proposed to enhance the performance of motor drive system during last two decades. In this paper, a sensor-less drive of induction motor based on a new hybrid cascaded multilevel and SVM controls are presented. In the proposed drive system, the main inverter and the conditioning inverter are connected together to drive motor, but only the main inverter is supplied by DC voltage source. The conditioning inverter just uses suspended super capacitors as its power source. The main and conditioning inverters can be either H-bridge inverter or 3-level NPC inverter. Different topologies are chosen according to different applications. Thanks to the proposed power flow management associated with the SVM control method, the conditioning inverter can be used to store and reuse the braking energy of motor. Therefore, considerable energy efficiency improvement is achieved when compared with conventional H-bridge inverter. Additionally, the conditioning inverter can improve the system dynamic performance. This control scheme finds wide applications, especially in the electric vehicle motor drive and marine propulsion system.