PMU Based Short Circuit Capacity Estimation and Experimental Verification on an Analog Simulator

This paper proposes an estimation method of short circuit capacity using PMU (Phasor Measurement Unit) measurements (synchrophasors) of voltages and currents during normal load variation. In the proposed method, the Thevenin equivalent circuit, which consists of a voltage source in series with a network impedance, is estimated from time series of high resolute PMU data. A robust optimization method is applied to realize the better estimation results even under various measurement noise, small scale variation of the system conditions, and other system uncertainties. At first, the accuracy of the proposed estimation method is verified by simulation studies performed on a simple power system with various load fluctuations. Then, the proposed method is verified using the actual Micro-PMU measurements obtained by simulating the power system on an analog simulator. The estimated results by the proposed method are found to be in good agreement to those obtained through the short circuit experiments on the analog simulator.