Research on detection and protection of zero-line breakage in distribution network

Zero-line disconnection in low-voltage distribution network will lead to a significant voltage rise in the lightly loaded phase due to three-phase load imbalance, which may cause damage to a large number of power-using equipment and requires real-time monitoring and timely protection. The current technology cannot be prepared to judge the zero-line operation condition, with low action reliability and high chance of misoperation, which cannot meet the current power supply reliability requirements. In this paper, we propose a method based on active excitation to detect zero-line disconnection in distribution network, which is accurate and effective, and the accuracy and effectiveness of the method are verified by experimental tests.