Online Synchrophasor-Based Dynamic State Estimation Using Real-Time Digital Simulator

Dynamic state estimation is a very important control center application used in the dynamic monitoring of state variables. In transient stability analyses, it is very critical to have accurate and time synchronized measurements with fast reporting rates. This paper presents and validates a time-synchronized phasor measurement unit (PMU)-based for dynamic state estimation by unscented Kalman filter (UKF) method using the real-time digital simulator (RTDS). The UKF algorithm implemented in the dynamic state estimation applies the sigma-point Kalman filter in the estimation of the best location of the measurement in the system state variables. The dynamic state variables of the system are the rotor angle and speed of the generators. The synchrophasor measurment of PMUs are bus voltage magnitudes, phase angles, active, and reactive powers of generators, which are newly applied in the formulated dynamic state estimation for estimate the rotor angle and speed of the generators. The performance of the UKF method is tested with PMU measurements as inputs using the IEEE 14-bus test system. This test system was modeled in the RSCAD software and tested in real time using the RTDS (real-time digital simulator). The dynamic state variables of multi-machine systems are monitored and measured for the study on the transient behavior of power systems.