Voltage stability: significance of load characteristics and current limiters

Voltage stability phenomena using a three-phase power system model are investigated. Measurements show that it is possible to run the system on the lower side of the PV-curve. Stable operation conditions of an induction motor load and a combination of induction motor and resistance load are discussed. The effect of generator current limiters on the system PV-curve is illustrated by measurements. It is shown that the armature current limiter has a more severe effect on voltage stability than does the field current limiter. The load characteristic is important for voltage stability once a current limiter is activated