At present, when the substation GIS is expanded, it must be installed during power outage, which will cause certain economic losses. In response to the above problems, the industry has introduced the design concept of double isolation breaks, which can safely isolate the live running lines from the newly expanded equipment, and realize the function of non-power outage during the expansion of GIS equipment.

Aiming at market demand, the company organized elite troops to carry out key technical research on double-break disconnectors. In 2022, the company has completed the design and test of 252kV double-break disconnectors and has promoted them to engineering applications. However, there is no mature product of 126kV GIS double-break disconnectors yet. In order to seize the market opportunity, the company has accelerated the research and development of 126kV products.

Combining the product characteristics of 126kV GIS, the project team creatively proposed a central symmetrical crank-connecting rod mechanism to achieve the same separation and closing of the two breaks. Through the simulation optimization of the electric field of the internal conductor, the kinematic simulation optimization of the transmission system, and the strength simulation verification of the load-bearing components, the research and development design of the 126kV double-break disconnector was completed in March and passed the company's design technology review.

At present, the parts are being produced intensively, and after the parts arrive and are assembled, type tests will be carried out for verification.