A Novel Approach to Practical Matrix Converter Motor Drive System With Reverse Blocking IGBT

Ⅰ. INTRODUCTION AMOTOR drive system with a conventional inverter has several problems, for example, large input current harmonics in case of accompanying a diode rectifier. Moreover, an electrolytic capacitor will be big and costly if a long lifetime is required. In addition, the conventional system needs a charge up circuit for the dc-link electrolytic capacitor and a 'breaking unit' composed of a switch and a resistor to dissipate a generated power from the motor. Usually, a pulse-width modulated (PWM) rectifier is applied for the input circuit in order to reduce the input current harmonics and to realize a generation from the motor. However, the PWM rectifier reduces efficiency and in-

1. INTRODUCTION AMOTOR drive system with a conventional inverter has several problems, for example, large input current harmonics in case of accompanying a diode rectifier. Moreover, an electrolytic capacitor will be big and costly if a long lifetime is required. In addition, the conventional system needs a charge up circuit for the dc-link electrolytic capacitor and a “breaking unit” composed of a switch and a resistor to dissipate a generated power from the motor. Usually, a pulse-width modulated （PWM） rectifier is applied for the input circuit in order to reduce the input current harmonics and to realize a generation from the motor. However, the PWM rectifier reduces efficiency and increases the volume of the system due to the need for a boost-up reactor.