An Induction Motor Drive Using an Improved High Frequency Resonant DC Link Inverter

An induction motor drive is presented using an improved high frequency resonant dc link inverter. The resonant circuit was systematically analyzed first to establish the criteria for initial current selection, and a new circuit was then proposed to establish the bidirectional initial current. The proposed current initialization scheme solves voltage overshoot and zero crossing failure problems in the ordinary resonant dc link inverters. A 3-phase 3-kW-IGBT based 60 kHz resonant link inverter has been constructed and successfully tested with an induction motor drive. The speed control system is implemented using two microprocessors-TMS320C25 for computation and INTEL 80386 for monitoring and user interface. Experimental results are presented to show superior operation of the proposed resonant dc link inverter drive.