Fault detection and location on 22kV and 11kV distribution feeders

AGL Electricity (AGLE) is one of the four privately owned electricity distribution companies in the Australian State of Victoria. Due to its operations in a regulated environment, AGLE's objective is to meet the distribution network performance standards set by the Victorian government's Essential Services Commission (ESC). Two performance measures are of major importance: average minutes off supply per customer and average number of intermptions per customer. These performance measures are adversely impacted by unplanned outages caused by faults occurring mainly on overhead distribution feeders. To improve these two performance measures, there has been a need to implement a scheme on AGLE's overhead distribution network that would contain long term effects of a fault within the feeder section that directly experienced the fault, leaving the remaining feeder sections and their customers on supply. To achieve this goal a means of fault detection and location, augmented by automatic isolation of the faulty feeder section, is required. To that extent, AGLE was faced with a dilemma presented by typical fault detection and location scheme applications on complex distribution networks, i.e. reliable fault location resolution versus affordable implementation and maintenance costs. This dilemma was resolved through the extensive feasibility study carried out by the author of this thesis