Secondary voltage-VAr controls applied to static compensators (STATCOMs) for fast voltage control and long term VAr management

This paper presents the concept and applications of secondary voltage-VAr controls applied to static compensators (STATCOMs) for fast voltage control and long term VAr management. The main purpose of the secondary controls is to ensure that an adequate range of the STATCOM dynamic capability is available for major system disturbances. The output of the secondary controls presented here call for the switching of capacitor banks to "reset" the reactive power output of the STATCOM to a prespecified level after a system event or during the course of a daily load cycle, or for fast voltage control. Two recent applications of STATCOMs coordinated with local and remote capacitor banks for the purpose of fast voltage control and long term VAr management are presented.