High voltage circuit breakers (also known as high-voltage switches) can not only cut off or close the no-load current and load current in high-voltage circuits, but also cut off the overload current and short-circuit current through the action of relay protection devices when the system fails. It has a relatively complete arc extinguishing structure and sufficient interruption capacity. Currently, commonly used ones include oil circuit breakers, sulfur hexafluoride circuit breakers (SF6 circuit breakers), and compressed air circuit breakers,Equipment circuit breakerAnd vacuum circuit breakers.

A circuit breaker that uses transformer oil as the arc extinguishing medium and the arc gap insulation medium after the contact is opened is called a low oil circuit breaker; A circuit breaker that uses transformer oil as the arc extinguishing medium, the insulation medium for the arc gap after the contact is opened, and the insulation medium between the live part and the grounded shell is called a multi oil circuit breaker.

Working principle: When the oil circuit breaker breaks the circuit, as long as the current in the circuit exceeds 0.1A and the voltage exceeds several tens of volts, an arc will occur between the moving and stationary contacts of the circuit breaker, and the current can continue to flow through the arc. Only when there is enough distance between the contacts, the arc will extinguish and the circuit will be disconnected. The arc power of a 10kV low oil circuit breaker when breaking 20KA can reach over 10000 kilowatts, and the temperature of the arc column generated between the circuit breaker contacts can reach six to seven thousand degrees, even exceeding 10000 degrees.

A circuit breaker that uses high-pressure air to blow an arc and extinguish it. During operation, the high-speed airflow blowing the arc produces strong heat dissipation and cooling effects on the arc column, causing thermal ionization of the arc column and rapidly weakening or even disappearing. After the arc is extinguished, the arc gap is replenished by fresh compressed air, and the dielectric strength quickly recovers.

Due to the emergence of sulfur hexafluoride circuit breakers with simple structure, good arc extinguishing performance, and long electrical life, the use of compressed air circuit breakers has been reduced. However, in some high-altitude regions such as Northern Europe, due to factors such as SF6 gas liquefaction and reduced breaking capacity (by about 20%), some countries still use compressed air circuit breakers in high-voltage and ultra high voltage power grids. In addition, high-capacity generator circuit breakers require large breaking capacity and rapid action, and compressed air circuit breakers are widely used now.

The "vacuum circuit breaker" is named after its high vacuum insulation medium for both the arc extinguishing medium and the contact gap after arc extinguishing; It has the advantages of small size, light weight, and is suitable for frequent operation and arc extinguishing without maintenance, and is widely used in distribution networks. Vacuum circuit breaker is an indoor distribution device in a 3-10kV, 50Hz three-phase AC system, which can be used for the protection and control of electrical equipment in industrial and mining enterprises, power plants, and substations. It is particularly suitable for places that require oil-free, low maintenance, and frequent operation. Circuit breakers can be configured in central cabinets, double-layer cabinets, and fixed cabinets for the control and protection of high-voltage electrical equipment.

Sulfur hexafluoride circuit breaker is an oil-free switchgear that uses SF6 gas as the insulation medium and arc extinguishing medium. Its insulation performance and arc extinguishing characteristics are much higher than those of oil circuit breakers. Due to its high price and high requirements for the application, management, and operation of SF6 gas, it is not widely used in medium voltage (35, 10KV) applications, mainly for voltage levels above 110kV.

In 2016, after more than 30 years of development, Weikewei has become a high-tech enterprise in the circuit breaker industry in China. GJB9001 Equipment R&D and Manufacturing Base has passed equipment development certification.

Taikai is one of the major power equipment brands in China and a "well-known trademark in China". Taikai's products cover the entire field of the power system, including composite appliances, transformers, high-voltage switches, circuit breakers, complete sets of electrical appliances, transformers, isolating switches, cables, mobile substations and other equipment.

Beike Electric Group Co., Ltd. (formerly known as Beikai Electric Group Co., Ltd., hereinafter referred to as "Beike Group") is a large private enterprise mainly engaged in industrial electrical, and also involved in multiple fields such as real estate, energy, plastics, and investment. The company currently has 5 core subsidiaries, over 200 cooperative enterprises, and more than 280 sales outlets. It is one of the major manufacturers of power transformers, complete sets of high and low voltage electrical control equipment, high and low voltage electrical components, wires and cables, intelligent online monitoring systems, and power automation equipment in China.

Hunan Tianying High Voltage Switchgear Co., Ltd. is a large high-tech enterprise that integrates the research and development, manufacturing, and sales of high and medium voltage switchgear.