Congestion Management Using Coordinated Control of Facts Devices and Load Shedding

The development of a control system and control strategies capable of governing multiple flexible AC transmission system (FACTS) devices in coordination with a load shedding is described here. The main purpose of the presented coordinated control system is to remove overloads caused by unplanned line outages in transmission network. A sensitivity analysis was used to find out an intercoupling between a variation of set points of different FACTS devices and a volume of load shedding with a variation of active power flow in transmission lines. The proposed control system is based on linearized expressions in steady state. Therefore, a coordinated control process does not require intensive computations. A prototype of the coordinated control system is suitable for a real time implementation. It constantly monitors power flows in a test transmission network and generates appropriate control signals to each load and FACTS device in order to maintain an admissible power flow level. It has been interfaced with load flow software to test its effectiveness through non-linear simulations using the IEEE 30 bus test power system as the study case. The results obtained are discussed.