Effects of Sudden Increase of Dynamic Loads on the Voltage Stability of South China Power Grid and Solutions with STATCOM Application

The securities of large load centers are increasingly threatened by the problem of transient voltage stability, which happened frequently recent years in many countries. One of the most important scenarios causing voltage instability and voltage collapse is the sudden increase of large numbers of dynamic loads. This paper presents the detail model of the sudden loads, employing time-domain simulation method to assess the effect on South China Power Grid using NETOMAC programme. The digital simulation results show that the voltage may collapse or recovery too slowly in the conditions of sudden increase of dynamic loads. Dynamic reactive power compensation is needed, and STATCOM is efficient to stabilize the voltages without load shedding.