Time Synchronization Method of Low-Voltage Distribution Network Based on Wi-Fi and Voltage Detection

Under the background of frequent electric fires caused by leakage and arc faults, the low-voltage distribution network uses the Internet of Things technology to solve the problem of low-voltage monitoring, so as to ensure the safe use of electricity. In order to tag the collected data with time tags, a large number of low-voltage terminal units need to have time synchronization function, while the cost and accuracy of existing time synchronization methods cannot adapt to the demand of low-voltage distribution network monitoring system. Based on analyzing the demand of low-voltage distribution network monitoring function for time synchronization, this paper puts forward a time synchronization method combining WiFi communication with voltage detection by taking advantage of the characteristics of short low-voltage line and small voltage phase angle change at both ends of the line. Time synchronization of low-voltage terminal unit at the time when the power frequency voltage crosses the zero point, using WiFi communication to transmit time synchronization commands. This method is economical and does not require additional equipment. Finally, the feasibility of the method is verified by building a test system, and the time synchronization accuracy can be within 1 ms.