Identification of Parameters of the FACTS Models for Power System State Estimation

The smart grid concept implies using FACTS devices as one of basic elements of the electric power system (EPS). To form the model for the EPS current state, state estimation (SE) methods are used. The EPS control quality depends on the obtained model compliance with EPS's real state. Until recently, the models for the present-day FACTS devices based on power electronics were not involved into the design diagram when solving the SE problem. Over the last few years, a team at the Melentiev Energy Systems Institute of the Siberian Branch of the Russian Academy of Sciences (MESI SB RAS) has studied this issue. The parameters of equivalent circuits of many FACTS devices vary depending on the PS state. Therefore, the issue of determining these parameters when developing the grid design diagram is relevant. Involving the FACTS equivalent circuit parameters in the state vector, when solving the SE problem, enables identification of device parameters. The authors address the algorithms identifying parameters of the equivalent circuit and control variables of some FACTS devices: thyristor-controlled series capacitors (TCSC) and static VAR compensators (SVC) at estimation of the power system state. The models for these devices were involved in the test circuit of the Irkutsk EPS 500 kV fragment. They provide results of the calculations performed at real SCADA-measurements.