Mitigating Congestion in a Power System and Role of FACTS Devices

Table 2

Applications of FACTS devices in power system operation for congestion management.

Operating problem	Corrective action	FACTS devices
(i) Voltage limit:
(a) Low voltage at heavy load	Supply reactive power	STATCOM, SVC
(b) High voltage at low load	Absorb reactive power	STATCOM, SVC, TCR
(c) High voltage following an outage	Absorb reactive power; prevent overload	STATCOM, SVC, TCR
(d) Low voltage following an outage	Supply reactive power; prevent overload	STATCOM, SVC
(ii) Thermal limits:
(a) Transmission circuit overload	Reduce overload	TCSC, SSSC, UPFC, IPC, PS
(b) Tripping of parallel circuits	Limit circuit loading	TCSC, SSSC, UPFC, IPC, PS
(iii) Loop flows:
(a) Parallel line load sharing	Adjust series reactance	IPC, SSSC, UPFC, TCSC, PS
(b) Post-fault power flow sharing	Rearrange network or use thermal limit actions	IPC, TCSC, SSSC, UPFC, PS
(c) Power flow direction reversal	Adjust phase angle	IPC, SSSC, UPFC, PS