Insulated cable thermal and life expectancy estimation under non-sinusoidal operating conditions

This paper deals with the thermal behaviour and life expectancy analysis of power insulated cables under distorted voltage and load current conditions. The proposed methodology utilises classical IEC-287 electrical and thermal models and extends the approach to cope with mutual thermal interaction between phases. This allows for independent three-phase representation and both thermal and electric equations are solved in a simultaneous way. This comprehensive manner of representing the phenomenon is then implemented into a time domain program. Computational studies are then performed to evaluate the cable temperature rise as well as the effect upon life reduction under distorted voltage and current conditions.