Battery Energy Storage System Integration in a Combined Cycle Power Plant for the Purpose of the Angular and Voltage Stability

Abstract

The introduction of the renewable energy sources in the electrical network is something necessary in the ecological transition context. This integration forces the grid operators to change the way to generate electrical power by favoring sustainable sources against traditional techniques. That means, adapt the grid code to provide the same energy quality for the end-customer despite the growing grid instability. Fast acting systems become more and more necessary to stabilize the grid by limiting the frequency, power and voltage swings. The integration of an electrochemical storage system at different connection points of the network is a solution technically studied over the last decade. In this article, the BESS will be connected inside a powerplant with a focus on the hybridization of the sources. Services as the angular stability and the plant voltage regulation are described however services concerning frequency regulation or plant design improvement are not approached. The hybridization concerns the synchronous machine, the associated excitation, the storage and the control system. The expected benefits for the grid operators are the enhancement of the flexibility, the robustness and the electrical quality towards a more and more constraining grid instability. Different services will be presented describing the integration concept, the potential connections, the sizing or some operating profiles. These services will concern the small-signal stability, the transient angular stability, the voltage regulation and the voltage disturbances (flicker, harmonics…). A simulation has been done with Matlab/SimulinkTM to show the benefits of the solution under the technical requirement specification n°6 of the French grid operator.