Measurement and Analysis of Capacitive Current in Ungrounded System of Distribution Network

The 10,. … 35kV distribution system is a neutral ungrounded system, and its fault is largely due to the excessive capacitive current when the line is single-phase grounded, which makes it unable to stop the arc by itself. This paper introduces a method of capacitive current test technology. By injecting the frequency conversion measurement signal of small current into the PT secondary opening triangle of the system, the injected measurement signal is calculated and analyzed. This method is applied in Qinghai power grid. It is of great significance to determine whether to configure and how to configure the arc suppression coil to compensate the capacitive current and improve the reliability of the equipment.