Coordinated and Optimal Voltage Control in Active Power Distribution

One of the main technical challenges of an active distribution network is to maintain an acceptable voltage level in the system. This has initiated efforts in using various voltage control strategies to regulate the network voltage profile so that the voltage is maintained at its allowable voltage limits of 0.95 per unit to 1.05 per unit. A number of voltage control methods have been applied to solve voltage control problems associated with the connection of DGs in a distribution system. These voltage control strategies may be classified as decentralised or distributed and centralised or coordinated voltage control. In this work, different decentralised voltage control methods have been considered, namely, power factor control, on load tap changer control and generation curtailment control. From the literature, a number of coordinated voltage control strategies have been implemented to provide better and faster control to the system. In this research, the three decentralised voltage control methods are coordinated using fuzzy logic by considering the load bus voltages and DG power as inputs and the voltage control actions as the outputs.