A new approach to improving the sensitivity of earthing relay and reducing the over-voltage in 6 kV grid of open-pit mines

Purpose. Earthing relays are utilized very commonly in open-pit mines for disconnecting the failure part of 6 kV electric system from earthing incident. Much previous research is mentioned on searching either an optimal method improving effect or improvements reducing overvoltage caused by grounding separately. The paper presents a new approach to not only sensitivity but also limiting over-voltage. A algorithm proposed control automatic connection additional resistor order achieve both above purposes relay. Methodology. propose controlling diagram implemented PROTEUS get 3U0 signals. main components appeared when feeders were faulted earth. Afterward, detecting signal as input simulation MATLAB and analyze wave forms responded zero sequence voltage. Findings. utilizing that auto-controlled auto-connect open-triangle coil measurement transformer at moment earth fault. This aims increase relay well reduce overvoltage. finding results factors voltage magnitudes healthy phases, which will be compared with corresponding values there no prove effectiveness method. Originality. useful increasing current enhance Practical value. could used design device aiming improve safety grid open pit faults occur.