Research On The Loop Closing Technology Of Guang Zhou Tian He District Low Voltage Power Distribution Network

According to the statistics of user outage time by the guangzhou power supply bureau, the planned outage time is more about 80% than the annual outage time in a year, which seriously restricts the improvement of power supply reliability, and in the scheduled outage times, 10 kV switch room maintenance, add the switches, etc. which are the very big proportion. And the other one of the main reasons for the user power outages is the transformer damaged. At present, the low voltage distribution network of Guangzhou city has the characteristics of high load density, power consumption and reliability, and the old city’s distribution network is relatively weak, the equipment is relatively backward, and the load and power supply capacity is poor.As the user’s demand for continuous and safe power supply continues to increase, how to further improve power supply reliability becomes an urgent need to solve the problem. Power supply department has been exploring new power transmission and transfer mode, which 10 kV distribution network power supply is generally based on "when power suply stoped,it will be turn;if can turn must be turn", but the 0.4kV low voltage automatic closing loop operation is still in the blank.Based on the analysis of the existing power supply mode of Tianhe District Guangzhou low voltage power distribution network, this paper discusses the feasibility of the power supply mode of low voltage power closed loop distribution network in this area, and design some modes of low voltage power closed loop, then using PSCAD/EMTDC software establish the closed loop modes,Analysis of the Closed loop current,find out the key factors influencing the low voltage closed loop,in oder to provide certain theoretical basis to the low voltage distribution network operating in closed loop and intelligent for the switch device development.