Distributed Methodology for Reactive Power Support of Transmission System

This paper deals with the provision of reactive power support from distribution grids to the transmission system. To this end, a new distributed control scheme is proposed that coordinates the reactive power output of distributed generation (DG) units to meet a predefined reactive power set-point at the point of interconnection of the distribution grid with the transmission system. The coordination process is implemented in an optimal way minimizing the reactive power of DG units, while also satisfying the technical limits of the distribution grid. Time-series simulations on the IEEE 33-bus network are performed to evaluate the performance of the proposed method against existing solutions.