Fault localization of a long power cable
Date of Issue2017-05-09
School of Electrical and Electronic Engineering
Transmission lines are the main channels that interlink consumers to the power grid. Documented in Singapore Energy Statistics 2016 by EMA, the demand for electricity consumption has been increasing over the years. In a span of one year, from 2014 to 2015, energy consumption raised by 2TWh. With the increase in energy demand, there is a need for more transmission lines to increase the rate of electrical energy transportation. On the contrary, transmission lines are constantly exposed to faults, be it man-made or natural. Thus, with more lines, more faults will materialize. A fault localization project is adopted to efficiently locate the fault point with equitable accuracy, which might serve its purpose to minimize downtime for industry application. The suggested technique was tabularized using transmission line theory, by treating voltages and currents as traveling waves. A fault location expression was formulated from transmission line impedance equation. Experimentations were carried out using RF (for frequency between 300kHz to 15MHz) equipment like VNA, to verify the expression. Two measurement setups were implemented with VNA, to measure six cases of DUT with different fault locations. The main fault that was examined is an open circuit fault. All measurements were corroborated via counterchecking of passive components and a simulation tool. Error of percentage serves as an indication on how well the technique is able to identify each fault location. For one-port setup, the error is less than 1% for 5m and 10m power cable, and for two-port setup, error falls below 7% for both the power cable. Even though, the two-port setup error was more than that of one-port’s, the results between 300kHz and 15MHz are more unswerving, which is less distorted, making it more reliable. Thence, with a technique that can locate fault distance with little errors, it provides personnel sufficient approximation on which section of the lines needs attention and restoration.
Final Year Project (FYP)
Nanyang Technological University