Implementation and Operation of Hybrid Multilevel and Multipulse Power Converter for High-Performance of Induction Motor Drives

One of most important research topics in induction motor drive configurations applied to medium voltage applications is power quality analysis, circuit complexity, and efficiency profile. This research work describes a hybrid six-level converter based on a neutral point clamped converter and cascaded two-level voltage source inverter suitable structure for medium voltage application of industry. Exhibited high-power hybrid converter ensures high power quality at motor terminal of the drive system. Furthermore, a thirty-pulse multipulse AC-DC converter is designed and implemented, which supplies power at DC-link terminal of hybrid inverter as well as improves power quality performance at input terminal of drive system. Secondary winding of multi-winding transformer is designed with phase displacement technique; due to this, harmonic components injected to grid by one rectifier are canceled out by harmonic components of other rectifiers. Feasibility of exhibited power converter circuit for induction motor drive systems is verified by computer simulation for a 400hp induction motor.