Problems And Improvement Methods Of Xin Hui Area 10kV Distribution Network Connection Mode

Xinhui District, a famous overseas Chinese hometown, is located in the southwest of the pearl river delta. It belongs to Jiangmen City, Guangdong Province. It ranked 62 nd in Chinese top 100 counties in 2013 and 2014 while 2015 it rose to 55 th. The urban area in Xinhui began cabling modification in the early 1980 s. Due to the imperfect distribution network planning mode, the current power distribution network connection has fell into chaos, which has produced a series of problems. E.g. The line is roundabout, part of the line is too long, the line loss is pretty large, line terminal voltage is too low, the branch lines are too many and too long, the line ring network is difficult and so on.The direct cause of the problem is that the urban construction is scattered and disorderly and the old distribution network connection mode is not scientific. Nearby access to the distribution station is mainly used in the old mode, this way is easy to make the line serpentine extension and produce too many and too long branches, which results to grid chaos. It would not conducive to the power grid transition to the future standard grid. From a philosophical point of view, the error of the old mode is the isolation of the inner link of the lines.In order to make the power grid adapt to the urban construction and the characteristics of the disorder, a new mode must be explored. From the view of philosophy, the new method has to explore all kinds of lines’ hidden connection and make full use of the temporary resources, which can be used by the other line construction. Take the Paris city 400/25/20 kV grid structure, the United States "4 x 6" connection mode, the two large single radiation line model of multi branch program for reference, I want to explore a new mode by using system thinking.The new mode mainly includes three aspects. Through mutual cooperation among various aspects, we can overcome adverse factors of the urban construction which is scattered and disorderly as well as achieve the orderly development of power grid. First, we use the long-range planning to guide the recent one. Second, we extend a branch from the adjacent lines or the side ring network to supply the temporary power. Third, we use the way that one wire supply power to several trunk lines which develop parallel, and then gradually separate power supply.We quote Xinhui urban annual maximum load rate data of 2014, with the distribution network operation experience, to analyze the feasibility of the new method.The new mode has many advantages: on one hand, it can effectively avoid the roundabout and improve the reliability of power supply. On the other hand, it is not only conducive to the smooth transition of the current grid, but also conducive to the construction of a strong fibernet. At the same time, it is good for the second level load user to pull in double circuit line as well as benefit the large residential area to achieve multi-lines’ power supply. The new mode’s economic benefit and the reliability of the power supply are much higher than the old ones, which shows its superiority. The “China Southern power grid design guidelines for the county power grid” says the cable network should avoid the use of branch wiring. But in this paper, the new approach requires active separation of multi-channel branch line in the initial stage of the line construction. This way is not contrary to the “China Southern power grid design guidelines for the power grid”, but more understanding the guidelines.In order to improve the image and operability of the new mode, several typical examples are summarized in this paper, which is a solution to the common problems of distribution network planning.The new mode is superior to the old one, but it is not perfect. It needs further testing, correcting the error and riching the connotation in the constant practice.