Fully Distributed Voltage Control in Subtransmission Networks via Virtual Power Plants

Abstract

In this paper, we propose a fully distributed control approach to deal with voltage violations in a subtransmission network with high penetration of wind power. The controllers used are virtual power plants (VPPs) in the subtransmission network. During the control process, each load bus monitors its own bus voltage. If there is a voltage violation detected, then all VPPs will be activated at once to provide necessary reactive power support. The reactive power change required for each VPP is calculated through two step communications based on different purposes. The first step communication aims to calculate a single sensitivity needed for each load bus with VPP, whereas the second step communication aims to calculate the final reactive power change needed for each VPP based on the sensitivities obtained through an average consensus. Semidefinite programming is used in the second step communication to optimize the weight matrix such that the convergence speed for the average consensus is the fastest possible. The effectiveness of the proposed control scheme is tested through a modified IEEE 14-bus system with wind farms.