1. Product Overview

Most of China's 3kV ~ 66kV distribution network adopts small current grounding mode, that is, neutral point non-effective grounding method, including neutral point ungrounded system and neutral point arc suppression coil or large resistance grounding system. The advantage of the neutral point non-effective grounding system is that in the case of single-phase grounding, it is possible to automatically extinguish the arc and restore the insulation in most cases. However, in the event of a permanent ground fault, in order to prevent the fault from expanding due to the rise of the non-fault phase voltage, the fault line must be determined and removed as soon as possible. This raises the problem of single-phase ground fault line selection. This problem has not been well solved for a long time, which restricts the development of distribution network automation.

2. Product Features

The company's small current system grounding line selection device is the latest product developed on the basis of the "small current grounding line selection device" in the current domestic market. When a single-phase ground fault occurs in a small current grounding system, the device has the function of automatically alarming and accurately finding the faulty line. The problem of long-term reliable operation of the device in harsh environments is solved prominently. The structure is more reasonable and light, and can be used for the transformation of old power plants and substations, as well as for new power plants and substations, and directly constitutes an integrated automation system.