Research On The Intelligent Controller Of Demarcation Load Switch

The paper analyzes the general situation and latest developments of the technology application of load switching controllers in domestic and international distribution network boundaries. At present, there are series of security incidents in the actual use of the cut-off switch, for example, because of PT insulation aging, an explosion injury may happen, and because of the lack of intelligent and less use of electronic sensors, the controller is large and inconvenient to use. so this paper presents a research study of new boundaries switch controller, that is, through removing PT on the cut-off switch, while more electronic sensors is in the place of the existing transformer to capture the zero-sequence current and zero-sequence voltage and the built-in lithium battery provides power for the cut-off switch controller. In order to meet the long-term use, a dedicated and intelligent circuit has been designed. That is, when the power supply line is in normal working, the low voltage current will maintain the normal operation of signal acquisition, and by measuring the signal, the controller can automatically identify and enter a dormant state. Once the side load fails, the controller will start to work within the prescribed time, which is, quickly cut off the connector between users and the distribution network to ensure the normal and safe operation of the grid. Therefore, under the identification working state, a controller with built-in lithium battery-powered can make the life up to several years.After years of research, Cut-off switch control has been installed the outside PT instead of the inside one to reduce the size of the controller. But even so, there are explosion accidents caused by lightning concentrated. Therefore, the research of this article will focus on removing PT, using electronic sensors to replace the original transformer, and how to reduce power consumption and so on. And then it will solve the problem of controllers’safety and long-time using with low cost, while it will effectively reduce controller’s size to greatly facilitate the safe operation of distribution network, and has great social and economic significance on reducing losses of grid.