A switching loss study in SPWM IGBT inverter

Abstract

This work discusses an exact mathematical approach of calculating the IGBT turn-on, turn-off and on-state energy losses. Instantaneous voltage and current values are studied, linearized and employed to formulate the equations needed to calculate the IGBT switching loss. The inverter employs a switching pattern commonly known as sinusoidal PWM (SPWM). With this popular switching pattern, switching losses are derived for a common 3-phase inverter. Waveforms describing each switching states are developed. Mathematical equations describing the switching waveforms are formulated. The net switching loss is compared with that of the inverter to make sense of the process of loss in an inverter.