Research on True-type Test Technology of Intelligent Circuit Breakers and Intelligent Integrated Terminals in Distribution Networks under Different Faults

With the proposal of the dual carbon goal and the rapid development of new power systems, the distribution network is an important part of the power grid, and the operation of the distribution network has also been greatly challenged. The most prominent problems are fault handling and topology identification. In order to solve the above problems, new equipment such as intelligent circuit breakers and intelligent integrated terminals have been developed, but the functions of the new equipment have yet to be verified. Conduct real system-level, turnkey pilot tests to verify the functionality of new equipment. This article designs and builds a low-voltage side true-type test platform for distribution networks, and proposes test plans for intelligent circuit breakers and intelligent integrated terminals under different faults. The functions of intelligent circuit breakers and intelligent integrated terminals are effectively verified through the low-voltage side true-type test platform for distribution networks, providing guarantees for the safe and stable operation of distribution networks.

I. Introduction

Against the backdrop of building a new power system with renewable energy as the main source, a large number of distributed renewable energy sources are connected to the distribution network. Featuring high proportion of renewable energy access into grids and high proportion of power electronics applications, and the randomness of supply-side randomness and demand-side randomness, various reliability problems have occurred in the distribution area, among which two problems are particularly noticeable: (1) The fault repair efficiency is low.The equipment intelligence level between the box transformer and the user's energy meter is not high and the system’s operation status cannot be monitored; (2) With the development of the distribution network, there are more and more branch lines. In case of a line fault, it is impossible to accurately spot the location of the fault point, leading to a time-consuming and labor-intensive trouble shooting. To resolve the above problems, new equipment such as intelligent circuit breakers and intelligent integration terminals are created. But there is no true type test platform for these new type equipments to conduct system-level and complete functional tests. So, the reliability of these equipments cannot be guaranteed, which not only directly affects the reliability of the power consumption on the user side in the power distribution area, but also increases the risk of distribution network operation [1] - [3].