Demand-side Volt/Var/Watt regulation for effective voltage control in distribution grids

Abstract

The continuously increasing penetration of renewables in combination with the unbundling of electricity markets during the last years, introduced serious voltage-related issues across the existing Distribution Systems. In order to overcome these issues operators sought for new, more effective ways to support voltage across distribution feeders and thus to ensure the quality of the electricity supply. Driven by the aforementioned need, in this paper we introduce an effective, demand-side Volt/Var/Watt (VVW) regulation scheme that is able to provide significant voltage support and assist in maintaining acceptable voltage levels across distribution grids. In particular, by considering certain passivity conditions on bus (load) dynamics, we design a VVW control mechanism that is able to regulate the voltage of feeders through the utilization of the available controllable loads. The proposed mechanism can be used either in a centralized or decentralized fashion and its formulation is carried out taking into account both the lossy and the dynamic nature of the distribution network. Its effectiveness is verified through several dynamic simulations on the IEEE 37 Node Test Feeder when either VVW or VV control is employed.