Case-based reasoning for coordinated voltage control on distribution networks

A significant amount of distributed generation (DG) is being connected to electricity distribution networks. This brings with it a number of network planning and operational challenges, including voltage control, protection issues, altered transient stability, bi-directional power flow and increased fault levels. Controlling network voltages, while also providing access for the increasing numbers of DG installations is one of the most important challenges. This paper describes a novel approach to voltage control for networks with multiple connected distributed generators, which employs case-based reasoning and online verification to select an appropriate set of control actions in the face of voltage excursions. The approach, case studies which illustrate its feasibility when applied to different networks and details of a prototype implementation using a commercially available substation computing platform are presented.

► An implementation of case-based reasoning was developed for network voltage control.
► Control measures were tap changes, generator output and power factor adjustments.
► Tests were performed on 11 kV and 33/132 kV model networks with distributed generation.
► Control measures were verified on-line before implementation on the test network.
► The system operates on commercial hardware within the required operational timeframe.