That’s why Powerco is pushing ahead with the digitalisation of its medium-voltage grid. Following a pilot phase to test the effectiveness of the technology, 1500 sets of Smart Navigator 2.0 (SN 2.0) intelligent overhead line short-circuit indicators from Horstmann will be installed in the medium-voltage grid.
Overall Network Reliability Objective
As one of the largest distribution system operators in New Zealand Powerco’s electricity network is approximately 28,000km in length and is responsible for numerous overhead lines in addition to the relatively fault-resistant underground lines. Many of the overhead lines are in rural areas with complex topography. This presents the network operator with some challenges. This is because the overhead lines are not only more prone to faults but also often require time-consuming and cost-intensive fault finding measures.
Powerco’s overall network reliability objective is to ensure that they meet their customers’ reasonable expectations regarding the quality at which they deliver their electricity. Their primary reliability measures are System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI), broken down into unplanned and planned outages. These measures are also what is reported to the Commerce Commission to meet quality of supply regulation obligations.