Detection of Periodic Forced Oscillations in Power Systems Using Multitaper Approach

An algorithm based on Thomson's multitaper spectral estimation and harmonic analysis techniques is proposed for the detection and frequency estimation of periodic forced oscillations in a power system. Unlike traditional periodogram-based techniques, the method does not rely on true ambient noise spectrum of the system, and can operate continuously in an online environment without requiring any system knowledge except synchrophasor measurements. It compares a test statistic derived from only measurements against a threshold, and the threshold is established from general expressions of the test statistic's distribution and the probability of false alarm. Performance of the detector is explicitly expressed using probability of detection expression, and evaluated using simulation studies. Results upon application of this algorithm to field measured synchrophasor data suggest usability of the technique for forced oscillation detection in practical monitoring of the power system.