Research On The Loop Closing Operation Analysis In 10kV Distribution Network Of Zhaoqing Power Network

The radial feeders are commonly distributed in the 10kV distribution network of Zhao Qing, it need the loop closing operation to achieve the transfer power in the case of facility inspection and preventive experimentation. But the actual mode to transfer power shall cut the power of whole line, and then transfer power to another line, which need stop the power supply of partial users. It also needs to stop the power supply of partial users to resume the quondam mode of power supply, when the facility inspection and preventive experimentation are finished. The time of power cut is about 10 minutes, that will affect users seriously, especially the important users such as hospital, government. So how to achieve the loop closing operation in the 10kV distribution network to transfer power without stopping power supply is a problem that power Supply Corporation shall solve.There are difficulty and risk to transfer power with the loop closing operation in the 10kV distribution network, the main are as below:1. The loop closing operation will generate large loop current current, which brings the overload problem of the line, so it needs to find out the factors that affect the Loop Current.2. The large impact current loop closing operation generates can make the relay protection device work falsely or disarrange the distributing of power, such will affect the safe operation of the distribution network.3. There are a lot of waterpower source connecting to the 10kV distribution network of Zhao Qing, which will affect the loop closing operation.4. There is no closing loop analysis software which can evaluate the risk of the loop closing operation with different function modes or loads.With the structure of the network and the characteristic of load in Zhao Qing, this paper analyses the problem and risk above, and discuss the feasibility of transferring power with the loop closing operation in the 10kV distribution network of Zhao Qing. It also develops closing loop analysis software based on the PSD-BPA mode of southern power grid and the EMS software. The software will supply data support to achieve the loop closing operation.The project can decrease the time of power cut, supply more reliable power to users, and improve the service ability of power Supply Corporation. The project has an important theoretical guidance and practical value to the safe operation of the network. Key words: 10kV distribution network, The loop closing operation, Loop current, Power grid...