Discussion On Adaptability Of 20kV Voltage Level To The Jiangdong Area Of Ningbo

With the great growth of power load density and the consumption in China, the 10kV voltage level widely used for medium distribution has obviously exposed its shortage at the aspects of transmission distance,power transmission and energy loss, in fact, the 20kV voltage level is one of the effective means to solve these problems. In this paper, the distribution network voltage levels and the voltage development of the major industrial countries were researched. Through the load forecast of Ningbo Jiangdong Area and analysis its distribution status quo, it is widely acceptted that the load density in Ningbo Jiangdong Area has reached to a high level and the distribution status quo can't meet the need of the community. The 20kV voltage leve which is mature in other countries could be applied in medium-voltage distribution system.In this paper, the technology and economic indicators of the 20kV voltage level is analyzed, as well as the reliability and the electtrovalence, and the 20kV material prices and factory production capacity is also researched. It is concluded that the adopt of the 20kV voltage level will achieve significant economic and social benefits, and will effectively alleviate the problem of insufficient power supply capacity of the 10kV distribution network. The adopt of the 20kV voltage level will also help China's power grid meet international standards, simplify the voltage level, and optimize the grid structure.The feasibility of 10kV step-up to 20kV is discussed in this paper. It is specifically stressed that before the renovation project, a wide range of analysis and evaluation, and a systematic planning target should be executed in first. The article also pointed out that the 10kV distribution network renovation project should satisfy the regional conditions and the principle of transformation technology.As to the 12th Five-Year Plan of Ningbo grid, several voltage configuration program are proposed in the paper, its economy than, and ultimately determine a reasonable program of medium voltage distribution network voltage level, and in voltage distribution network planning.