An Improved Fault Detection Method for Overhead Transmission Lines Based on Differential Tunnel Magnetoresistive Sensor Array Approach

Overhead transmission lines play a key role in ensuring power system security and reliability in this current smart society. The overhead transmission line operates in a very complex terrain thereby making it vulnerable to various kinds of faults. Most transmission line faults lead to interruption in power supplies and therefore the need for a fast repair to restore the system to its normal state. A fast, timely, and accurate fault detection technique will ensure speedy restoration of the system thereby reducing outage time. In this article, an enhanced transmission lines’ fault detection approach is presented. This scheme deployed a highly sensitive, low cost, and energy-efficient differential sensor to detect flux density variation measured along transmission lines. The fault detection algorithm is developed for the detection of faults in transmission lines. The development is implemented on a model transmission line and tested for various fault scenarios. Scaled-up laboratory experiments were also conducted to measure magnetic flux density and fault identification to verify the validity of the proposed technique as well as estimate the amount of current produced when a fault occurred. From the simulated and measured current produced during a fault, the proposed technique yielded an estimated error of 1.38%, while the CT and a commercial current probe gave errors of 10.99% and 17.68%, respectively.