Practical implementation of a dual inverter operates open ends induction motor

Abstract

This paper presents the practical implementation of three-level inverter using dual two-level inverter. A space vector PWM technique (SVPWM) is developed based on the combination of space vector from dual inverter feeding open end winding induction motor (OEWIM). A total of “64” combinations produce “19” operating vectors which make a hexagon shape similar to that produced by neutral point clamped three - level inverter (NPC). This proposed system eliminates the NPC inverter drawbacks of bulky DC link capacitor, which carry load current that makes neutral point fluctuations and results in DC component in voltage waveform. The “OEWIM”is obtained by removing neutral point using separate DC link is remove zero sequence harmonics; A soft starting for “OEWIM” is presented using V/F control scheme. The PIC18F452 microcontroller used to generate the SVPWM pulses that control OEWIM by VVVF control.