Dynamic reactive power optimization strategy for AC/DC hybrid power grid considering different wind power penetration levels

Abstract

With the increasing capacity of wind power integration and the further development of AC/DC hybrid power grids, the problem of voltage stability in the receiving end has become increasingly severe. The installation of dynamic reactive power compensation devices is a feasible measure to improve the voltage stability of the receiving end power grid. This paper proposes a dynamic reactive power optimization strategy for AC/DC hybrid power grids considering the integration of new energy sources. Firstly, a detailed mathematical model of the AC/DC hybrid system is established. In order to enhance the voltage restoration capability after a fault, the definition of a fault recovery indicator is provided. Subsequently, an optimal scheduling strategy for dynamic reactive power compensation devices is formulated to maximize the value of the fault recovery indicator. Considering the nonlinearity and non-convexity of the optimization model, trajectory sensitivity method and whale optimization algorithm are adopted to enhance the solution efficiency. Finally, an improved IEEE-9 test system is employed to demonstrate the effectiveness and feasibility of the proposed approach.INDEX TERMS AC/DC hybrid power grids; wind power; dynamic reactive power; fault recovery indicator; trajectory sensitivity method; whale optimization algorithm