2020 Volume 61 Issue 1 Pages 40-46
This paper describes new inspection equipment and a new circuit structure used for evaluating the lightning protection performance of earthing systems in railway substations. The new inspection equipment consists of an impulse generator and a measurement unit, and allows the inspector to measure the earth resistance, the high frequency earth impedance and the voltage difference of an earthing system without specialist knowledge. The new measurement circuit for the inspection of the earthing system only makes use of existing infrastructure components, i.e. independent earthing for a remote terminal unit, the earthing system of an adjacent substation and an overhead contact line. Therefore, the proposed circuit requires no temporary test earth electrodes for measurement.
