Comparative analysis of Pulse Width Modulated Voltage Source Inverter fed induction motor drive and Matrix Converter fed induction motor drive

Variable speed induction motor drives for constant torque applications often employ Pulse Width Modulated Voltage Source Inverters for exercising speed control through constant volts/hertz control. Although such drive systems offer a wide range of speed control, they however create severe power quality problems on the source side. In order to overcome these power quality problems, an alternative drive system has been proposed in this paper for exercising constant volts/hertz control in induction motors by means of Matrix Converters. Matrix Converters are a relatively new breed of AC voltage controllers that offer a controllable output voltage at unrestricted frequency while maintaining desirable power quality at input as well as output. Besides serving as an improved power quality drive, a matrix converter based induction motor drive offers single stage AC to AC conversion, hence eliminating the need for a heavy D.C link capacitor that is otherwise required in a conventional drive system.