Application of Shielded Buckle Type Casing Bushing in Substation

With the development of industry, environmental pollution is becoming more and more serious. The insulation protection of power system substations, especially the insulation protection of old substations, is becoming more and more important. Personal injury and death accidents caused by pollution flashover, condensation flashover, icing tripping, short-circuiting of small animals, and bare busbars in substations occur from time to time. More and more substations choose shielded button bushings for insulation protection.

Shielded button casing and heat shrinkable tube protection comparison:

The use of heat-shrinkable materials in the comprehensive insulation protection of substations can reduce the occurrence of such accidents, improve the reliability of the power supply system, and is of great significance to the safe operation of the power system. However, when the heat-shrinkable materials are used to transform the power system equipment, they need to be modified. The operation of disassembling equipment during power outage is inconvenient for construction, and the insulating sleeve is not tightly connected to the special-shaped joints, which makes it difficult to be fully enclosed. As the temperature of the busbar rises, its life will be severely attenuated and reduced. For environments with high humidity, it will be The heat source absorbs moisture severely, which further damages the insulation performance of the insulating material, and may cause breakdown discharge. In addition, the casing used in the open environment is prone to aging, deformation and damage, has a short service life, is inconvenient to replace the casing, and the cost is high.

In order to better eliminate the above shortcomings, shielded button bushings have begun to go deep into the application research of shielded button bushings in substations. In 2008, Tangshan Power Supply Company in China launched the full insulation treatment of dry-type reactors using silicone rubber, which has excellent insulation effect. Dry-type air-core reactors have undergone on-site insulation treatment, which proves that the insulation treatment process is advanced and easy, and it can be very convenient. Deal with the dry-type air-core reactor equipment in transit, so as to prevent small animals from entering the equipment interval and causing reactor damage. The man-made short circuit test proves that the reactor can effectively avoid interphase short circuit fire accidents caused by small animals climbing after being fully insulated.

Silicone rubber insulation coating has strong flame retardancy. Insulating materials for electric power equipment are required to be flame-retardant. The product is mainly composed of rubber-plastic blended polymers and added with excellent flame-retardant to make its flame-retardant reach FV-0 level and meet the flame-retardant requirements of power systems.

The silicone rubber insulation sheath has strong aging resistance. The service life of the silicone rubber insulating sheath can reach more than 20 years, which greatly reduces the cost of overcoating, the time of power outage and the economic loss caused by power outage.

The silicone rubber insulating sheath has excellent thermal conductivity, can effectively reduce the temperature of the busbar in operation, increase the current carrying capacity of the busbar, and solve the problems of aging and cracking caused by the rise of the temperature of the busbar.

The construction is convenient and fast. The time in the power system construction process is very limited, which requires simple and fast construction work. The silicone rubber insulating sheath and the busbars are bonded with a silicone rubber adhesive. The silicone rubber adhesive is applied by brushing, and then the silicone rubber insulating sheath can be directly covered. No special tools are required. Generally, one person The above construction operations can be completed. In addition, the insulating protective covering layer can be manufactured in the factory, and can be constructed on site, which saves costs and improves the sealing performance.

Silicone rubber insulation sheath has strong insulation. When power equipment is running, arcs are unavoidable in the rectifier cabinet. Because the silicone rubber insulating sheath has excellent insulation, it can greatly improve the insulation withstand voltage level of the busbars in the power distribution cabinet, and reduce the air breakdown and insulation voltage drop. Short-circuit failure, so as to avoid short-circuit accidents between busbars caused by small animals climbing, and ensure the safe operation of power grid equipment.