Testing of a hydropower plant's stability and performance using PMU and control system data in closed loop

Abstract

In response to recent concerns regarding deteriorating frequency quality in the Nordic power system, the Nordic transmission system operators have developed draft requirements for the provision of frequency containment reserves (FCR). These requirements outline extensive tests, which the power plant owners must perform to qualify to deliver FCR. In this study, the authors demonstrate that one can check these requirements by standard system identification techniques while the plant is in normal operation and by using measurements readily available from the plant's control system or from a phasor measurement unit (PMU). The validity of the proposed method is demonstrated using Monte Carlo Simulation, where they investigate the effects of the main assumption and potential non-linearities affecting the approach. Data from real power system operation is used to demonstrate the performance of the method.