Special cable development status

As the pace of national power grid construction continues to accelerate, our country attaches great importance to the construction of the power grid based on the ever-increasing power demand. For this reason, China has successively introduced a series of policies to accelerate the development of electric power.

From 2009, the State Grid Corporation of China began to comprehensively promote the implementation of "two types of three new" (ie, resource-saving, environment-friendly, new technologies, new materials, and new processes), saving corridor resources on the premise of ensuring the reliability of transmission lines. Improve the transmission capacity of the line, reduce the overall cost of construction and operation, and vigorously promote energy-saving wires.

Since the beginning of this year, China's energy-saving conductor pilot project construction has been "overwhelming." According to sources, the National Grid plans to fully promote energy-saving wires in 2014 and strive to achieve energy-saving wire replacement of ordinary ACSR at an early date. At the same time, along with the application of the National Grid Corporation's energy-saving conductor pilot promotion, the demand for energy-saving wires has soared.

As early as 2012, the State Grid Corporation of China carried out pilot applications for energy-saving conductors such as medium-strength all-aluminum stranded wires, and achieved comprehensive benefits.

In 2013, the State Grid Corporation of China comprehensively considered factors such as the production capacity and quality control of energy-conserving conductors, used transmission line projects with a high number of hours to carry out pilot projects for expansion, and improved the quality control guarantee mechanism for energy-saving conductors.

On the afternoon of October 28, the first example of a new type of energy-saving wire pilot line from Ningxia Power Grid to Ningxia Shizuishan Hub substation, Hui Nong Xia was completed. With the successful access of the line to the Huinong 220 kV substation, the first pilot line of the new energy-saving conductor in Ningxia Power Grid will be officially put into operation. The first energy-saving conductor in the Ningxia Power Grid used medium-strength aluminum alloy strands, which was also the first time in the northwest region.

At present, most of China's transmission lines still use ACSR, which has a conductivity of 53%. The energy-conserving wire (all-strength aluminum alloy stranded wire) has a higher electrical conductivity than steel stranded wire by 5.5%, and has the advantages of large transmission capacity, low resistance loss, corrosion resistance, and low construction cost. According to statistics, the loss of power transmission and distribution lines in the country amounts to 171 billion kWh, which is approximately 59.85 million tons of standard coal. If the domestic 20% of transmission lines adopt this energy-saving technology, the annual loss of the line can be reduced by more than 1 billion degrees, and 36 million tons of standard coal can be saved.

According to a power professional, the medium-strength all-aluminum alloy strands were treated with a special process, which greatly improved the creep resistance and reduced the chance of accidents due to creep. All of the aluminum alloys used in the structure were made of conductive aluminum alloy. Single strands are concentrically stranded. In this structure, the aluminum alloy wire simultaneously assumes the role of conductive and reinforcing core, and can completely replace the steel core and other additional reinforcing elements. In addition, the wire has no hysteresis loss and eddy current loss when used. At the same time, the problem of reducing the service life of wires due to electrochemical corrosion between different materials is also solved.