Stress Due to Transient Voltage Distribution in the Windings of Random Wound Motors Fed by PWM Converters

摘要

The presence of semiconductor switches like IGBTs and MOSFETs in pulse width modulated drives has increased the occurrence of steep fronted voltage surges (<500ns) in motors used as adjustable speed drives. Technical literature published confirms this. Most of the literature is confined to study on form wound windings and only portion of the literature deals with random wound coils. However, the combined effect of pulse duration and rise times, on intercoil and interturn voltage distribution has not received enough attention. Current technology uses IGBT drives upto around 50 kHz and MOSFET drives above 50 kHz. This study explores the combined effect on intercoil and interturn voltage distribution due to pulse duration and steepness with particular reference to random wound machines through modelling and simulation techniques.