The development of environmental protection gas global warming coefficient is only 5% of SF6, which can promote the upgrading of gas insulation equipment. Research and development of new insulation gas, to the power equipment to transport fresh blood, and get along with the environment, has given the electric workers no small pressure.

The major power equipment giants in the world are actively developing new environmental protection gases. 3M, GE and ABB companies in the United States have made breakthroughs, and are gradually forming technological monopoly advantages. Facing the strong leading advantages of foreign companies, several generations of electric power people in China are rehearsing, but still mainly stay in the laboratory research stage. "The research on environmental protection gas to replace six sulfur fluoride in China is still in the stage of exploration, and the gap is large compared with the similar foreign technology. The related research needs to be speeded up and deepened.

When the transmission line meets the special geographical conditions such as high drop and river, the transmission of gas insulated pipeline has gradually become an important supplement to the overhead line in recent years. The China Academy of electric power research organization, Ping Gao group and Xi Kai electric, has taken the lead in developing an UHV transmission pipeline with six sulfur fluoride insulation, in Huainan 3 substations in Nanjing Shanghai UHV AC project have been successfully applied. At the same time, the six sulfur gas hybrid gas hybrid gas transmission pipeline prototype developed by the national Power Grid Corp is charged in Wuhan UHV AC test base. China has accumulated many years experience in research and manufacture of UHV switchgear, which has laid a solid foundation for the development of power transmission pipelines with new environmentally friendly gases.

GE has applied the new environmental gas to the 420kV transmission pipeline in the subsequent research and development, and has made engineering applications. It claims the feasibility of the application of new environmental gas to the transmission pipeline. But 1000kV environmental protection transmission pipeline has high voltage grade, strict environmental protection and insulation. There are many factors that need to be considered in design, manufacture and operation. There are no related technologies at home and abroad. "If the new environmental insulation gas is applied to the voltage level of UHV 1000kV, it is necessary to solve the problem of" three saturation and a breakthrough ". With the increase of voltage level, the gap insulation, the insulation and flow ability of the surface tend to saturate, and the mechanical strength is difficult to break through.

Based on the research and development of 1000kV six sulfur fluoride transmission pipeline, the project has learned from the research experience of 420kV new environmental protection gas transmission pipeline and conquered the key technology of environmental protection pipeline transmission, and developed a prototype of new environmental protection gas, supporting insulator and transmission pipeline for 1000kV environmental protection transmission pipeline. "The project needs to solve the contradiction between the new gas insulation and environmental protection and the design problem of gas solid insulation system based on new gas. It focuses on the discharge law and gas solid compatibility of the gas solid insulation system in the environmental insulating gas, the design and manufacture of the key technology for the three pillar insulators used in the 1000kV transmission pipeline, and the operation and maintenance of the environmental protection transmission pipeline. Repair technology.

At home and abroad, only a small amount of potential six sulfur fluoride replacement gas and mixed gas have been studied in the gas solid insulation system. In our country, new environmental protection technology has not been mastered, and the research of discharge properties, insulation and medium recovery characteristics should be carried out. The compatibility of gas and solid material is the precondition of ensuring the reliability of the transmission pipeline. It is necessary to master the law of the interaction between the new environmental gas and its decomposed gas and the solid material, and put forward the gas and solid compatibility control method.

Electricity, heat and force should be subjected to multi stress in the operation of transmission pipeline. The characteristics of the new environmental gas make the insulation, flow and structural strength design of the environmental protection transmission pipeline and supporting insulators more difficult. The manufacturing process control of the three pillar insulators for the 1000kV transmission pipeline, the control and transmission of the surface morphology of the insulators, and the transmission of the transmission pipeline The inhibition of metal particles inside the electric conduit faces great challenges. We need to overcome the design and manufacturing technology of the three pillar insulators for 1000kV new environmental protection gas transmission lines, and provide the key components for the development of transmission line prototype units.

The technology of the hybrid preparation, performance detection, storage and transportation of the new environmental gas, the fault detection and positioning of the transmission pipeline, the monitoring and evaluation of the running state are all different from the existing six sulfur fluoride and its equipment operation and maintenance technology. It is necessary to carry out the research on the maintenance and maintenance of the new environmental protection gas for environmental protection transmission. The reliable operation of the pipeline provides sufficient guarantee.

The project is expected to develop an environmental protection insulated gas, basin insulator, three post insulator and a long 18m transmission line standard unit prototype for 1000kV environmental protection transmission line. The environmental protection gas has the same gas insulation performance of six under the same pressure, 80% of the sulfur fluoride, and the liquefaction temperature is not higher than -15 C. The research results of the project will provide strong support for the transmission bottlenecks in UHV, long distance and complex geographic environment, and can be applied to other power equipment, and continue to lead the upgrading of the environment friendly environment, with significant economic and social benefits.