Commutatorless Series Motor Drive for High Power Applications

Multi-MW, normal speed (1500-3000 rpm) industrial AC drives requiring slow dynamic torque response mostly employ thyristorized Load-Commutated Inverter (LCI)-fed wound field synchronous motors. These traditional drives are popular as Separately excited/Shunt Commutatorless Motors (CLMs), as the field winding of these motors are separately excited/controlled. This book deals with the development, analysis, design, simulation models and practical implementation including a position sensorless operation of a thyristorized commutatorless series motor (CLSM) drive in which the field winding of the synchronous motor is placed in the DC Link in series with the inverter. It is found to possess some advantages, like un-aided start-up for high power propulsion application, for which, it can be envisaged as an alternative to a separately excited/shunt CLM, usually employed for similar load applications. The simulation and test results on a laboratory prototype validate the proposition. The reported CLSM is rather novel and may replace the conventional CLMs in future. The content of this book will be useful for researchers, manufacturers and users of LCI-fed high power drives.