一、Background

Copper is an indispensable and important resource in China's power industry, since the 21st century, China's copper consumption has been rising year by year, but China's copper reserves only account for 3% of the world's total reserves, resulting in the current dependence of copper resources in China as high as 80%.

The large-scale promotion and application of copper-saving, economical and high-performance copper-aluminum composite materials in the power field is an important measure to promote the breadth and depth of "copper saving with aluminum" in the power field, improve the supply chain toughness of the power equipment industry, ensure the large-scale renewal of transmission and distribution equipment, and improve the economy of power grid construction.

二、 Import steps

In order to fully implement the national strategy of "saving copper with aluminum", effectively reduce the amount of copper used in the field of transmission and distribution, and improve the economy of power grid construction, the State Grid decided to introduce copper-aluminum composite materials, and the overall implementation plan:

(1) Preparation of application standards for copper-aluminum composite materials;

(2) Headquarters project demonstration;

(3) Pilot application verification;

(4) Preparing and revising national network enterprise standards related to copper and aluminum composite materials;

(5) Large-scale application of materials.

三、Implementation process

1. Preparation and promulgation of power line standards -- preparation of application standards for copper and aluminum composite materials

In October 2021, the power bank standard - DL/T2260-2021 "Guidelines for the Selection of Copper and Aluminum Composite Buses for Power Use" (see Annex 1), led by the State Grid Smart Grid Research Institute, was officially promulgated and implemented, with 7 State Grid secondary units, 2 scientific research institutes, 7 transmission and distribution equipment manufacturers, and 1 material manufacturer.

2. State Grid Headquarters project

In June 2022, in order to realize the design, trial production, verification and engineering application of medium and low voltage power switchgear based on copcopal-aluminum composite bus, the State Grid Headquarters project "Design, development and application technology research of high performance Copcopy-clad aluminum composite materials for electrical equipment" (see Annex 2 for the task book) was approved and started in September of the same year, the project leader is Shao Jinjiao Gao, Equipment Department of State Grid. State Grid Shandong Company is responsible for the lead, Smart grid Research Institute is responsible for technical coordination, project members include State Grid Beijing Company, Liaoning Province Company, Jilin Province Company, Mengdong Company, as well as Pinggao Group, Yantai Fuxinda.

Project process:

(1) Complete the comprehensive performance testing and verification of the new copper-aluminum composite materials and their products, and the test and assessment results prove that the properties of the materials meet the application needs;

(2) Based on the optimal design, trial production and test verification of the complete set of switchgear for cop-aluminum composite bus bars, complete set of equipment manufacturers Pinggao Group, Jilin Jinguan Electric, Xidan Baoji Electric, Taikai, Wisheng, ABB and other complete set of equipment manufacturers completed the design and related type tests of the complete set of switchgear for 35kV, 10kV, 0.4kV cop-aluminum composite bus bars

(3) Compilation of special technical specifications for the State grid collection bidding and the provincial company bidding;

(4) The first set of 10kV coppery aluminum composite bus switchgear will be safely operated for 22 months, and the project will be completed in June 2025.

3.试点应用

Cooperate with the headquarters project demonstration, start the pilot project within the jurisdiction of the company in 5 provinces:

(1) In July 2022, the 6-side 10kV copper-aluminum composite bus switchgear was connected to the grid in the substation project of Jilin Songyuan Power Supply Company;

(2) In September 2023, Taizhou State Grid "Green Town" demonstration project, 6 sides of 10kV copper and aluminum composite bus ring network cabinet hanging network power;

(3) In September 2024, the complete set of 10kV copal-aluminum composite bus switchgear was applied in the transformation project of Xingfa 66kV substation in Horqin Substation Area of Tongliao;

(4) Beijing Company Shunyi Yinjiafu 110kV Substation 58-side copper and aluminum composite busbar complete switchgear, included in the State Grid 2024 first batch of collective mining tender, complete installation in September 2024;

(5) In July 2022, Liaoning Electric Power Company and State Grid Smart Grid Research Institute completed the development and application of continuous casting copper aluminum composite tension clamp; In December 2023, Dalian Power Supply Company of the State Grid completed the development and application of a new type of copper-aluminum transition terminal.

4.State grid enterprise standard

In April 2023, the State Grid enterprise standard "Technical Specification for copper-aluminum composite Materials for bus bars of 40.5kV and below" was completed and submitted for approval, and the enterprise standard was officially implemented on August 25, 2024.