Primary and secondary deep integration pole-mounted built-in isolation circuit breaker products

Primary and secondary deep integration pole-mounted built-in isolation circuit breaker products designed based on the concept of green environmental protection and normal pressure sealing

1. Description:
ZW□-12 type common box type primary and secondary deep integration pole-mounted built-in isolation circuit breaker (hereinafter referred to as circuit breaker or switch) product, rated voltage of 10kV, rated current of 630A, used for 10kV power transmission and distribution systems with high reliability requirements, such as industrial and mining enterprises, commercial buildings, residential residential areas, seaports and multi-storey buildings. The power supply network is generally combined into a ring shape, and the high-voltage circuit is generally through the high-voltage load switch or circuit breaker and auxiliary control circuit to achieve load separation and closing control and fault protection. Its miniaturization and air-insulated normal pressure sealing design reduces the space resource occupation by more than 50% compared with traditional air-insulated equipment. It is an optimized design for the internal insulation structure of the mainstream switch on the market, which is convenient for outdoor installation and application.

The circuit breaker is a smart cloud column switch with environmentally friendly materials, economical price and convenient operation. All the primary conductive parts in the switch are enclosed in a stainless steel box. The box is insulated by air insulation + thermoplastic materials, the main switch adopts vacuum arc extinguishing, and the rotary isolating switch adopts integrated sealing technology. The secondary circuit adopts integrated control technology and supports data transmission function. When the equipment is installed and powered on site, the equipment will spontaneously send a signal to the master station for the first handshake. The master station will obtain the health status, coordinate position, operating environment and operating parameters of the equipment, so that the operation and maintenance personnel can grasp the equipment operation status in time.

Its technical advantages are mainly reflected in green environmental protection, strong environmental adaptability, safety and reliability, low maintenance, high life, small size, modularization, digitization, intelligence, easy maintenance and other aspects.

2. Green environmental protection design concept:
Green design, also known as ecological design, environment-oriented design, etc., focuses on the ecological balance between man and nature, and minimizes damage to the environment during the design process. In the current electric power industry, the demand for environmental protection of pole switches is increasing. In order to improve the competitiveness of our company’s pole switches in the market, we have developed a new green environmental protection, normal pressure sealing, air insulation concept design of the common box type primary and secondary deep integration pole built-in isolation circuit breaker products. All indicators meet the distribution network automation requirements of the State Grid and the Southern Grid.

3. Environmentally friendly raw materials:
The main insulation medium of the circuit breaker uses normal pressure sealed air insulation to replace dry air and traditional SF6 gas, while the traditional ZW20 and FZW28 common box pole switches use SF6 gas insulation. However, SF6 gas will cause a greenhouse effect; at the same time, during its production process or under the action of high energy factors, it will decompose and produce a number of toxic or even highly toxic, highly corrosive and harmful substances, which are extremely harmful to the human body. The insulation requirements are met by purifying and drying the air, and its normal pressure sealed air insulation reduces the application of difficult-to-degrade materials such as silicone rubber and epoxy resin.

All parts and production processes strictly control the content of harmful chemical elements in raw materials to minimize the generation of harmful substances in the production process; strictly control in accordance with the provisions of the EU RoHS and Reach regulations; the material recyclability rate after the product life cycle is more than 90%.

4. Miniaturization and maintenance-free design:
The circuit breaker is a fully sealed design at normal pressure, which is not affected by the external environment. It does not require special maintenance during the entire life cycle, and does not require replacement of wearing parts; the switch greatly reduces the lubrication and cleaning materials required for equipment maintenance year by year compared to ordinary air-insulated switches, and also reduces the consumption of manpower and transportation energy. In addition, in order to increase the surface creepage distance between conductors and between conductors and the ground in a small space, the switch uses its own umbrella skirt, connectors and inlet and outlet bushings to shield the uneven electric field of the conductor connection part inside the connector, effectively optimize the switch electric field, reduce the insulation distance, and the umbrella skirt can effectively increase the surface creepage distance of the insulation and improve the withstand voltage.

5. Built-in rotary isolation design:
The vacuum interrupter and rotary isolating switch adopt integrated solid sealing technology. Built-in high-precision current sensor and voltage sensor meet the requirements of the deep integration of primary and secondary functions of the State Grid. At the same time, it has the characteristics of high protection level, high safety, and high reliability.

The internal insulation capacity of the circuit breaker is the most important performance affecting the operation of the circuit breaker. The most serious problem in the actual operation of the traditional common box circuit breaker is that the internal insulation environment is damaged due to the reduced air tightness of the box, causing internal short circuit.

Through the design optimization work in various links such as product raw material selection, normal pressure sealing, maintenance-free design, and built-in rotary isolation design, we have maximized the reduction of material and energy consumption, the reduction of harmful substances, and the recycling and regeneration or reuse of products and parts.

6. Strong environmental adaptability:
All high-voltage components are sealed in metal shells, which are particularly suitable for harsh environments such as high altitude, severe cold, humidity, and dirt.

7. Safe and reliable:
Using normal pressure sealed air insulation, the primary live parts are arranged in the sealed box, the insulating medium between the live conductors and the ground is air (non-solid insulating material, except for supporting insulating parts and bushings), the air gap between the switch and the ground, between the phases and the isolation knife switch is not less than 125mm. The air pressure in the sealed box is always the same as the ambient atmospheric pressure, and the internal and external gas pressures are balanced by a device with air filtering function. The arc extinguishing method is vacuum arc extinguishing. The safety hazard of switch gas leakage is avoided, and normal operation will not be affected even in bad weather; the normal pressure sealed metal shell is reliably grounded to ensure the safety of operation and maintenance personnel.

8. Intelligence:
The vacuum switch and rotary isolation switch can have manual and electric operation functions at the same time, and the switch has intelligent functions.

9. Application cases:
Due to its green and environmentally friendly, miniaturized, normal pressure sealed air insulation, strong environmental adaptability and maintenance-free design concept. It meets the requirements of GB3906 and adopts a maintenance-free structure of fixed assembly. The structural design enables it to be safely operated, inspected, maintained and operated.

Since the successful development of our company’s ZW□-12 type common box type primary and secondary deep fusion column mounted built-in isolation circuit breaker, it has been widely accepted and praised by customers.