Time: 2022-01-10 Author: 铧正 Click: 394 Time
Circuit Breaker Dynamic Characteristic Tester
The high-voltage circuit breaker (or high-voltage switch) is the main power control equipment of the substation. When the system is in normal operation, it can cut off and connect the no-load and load current of the line and various electrical equipment; when the system fails, It cooperates with the relay protection to quickly cut off the fault current to prevent the expansion of the accident scope. Therefore, the working quality of the high-voltage circuit breaker directly affects the safe operation of the power system. It can not only cut off or close the no-load in the high-voltage circuit Current and load current, and when the system fails, the relay protection device is used to cut off the overload current and short-circuit current. It has a relatively complete arc extinguishing structure and sufficient current interruption capacity.
The main structure of the high-voltage circuit breaker is roughly divided into: the diversion part, the arc extinguishing part, the insulating part, and the operating mechanism part. The main types of high voltage switches are divided into: oil circuit breakers, air circuit breakers, vacuum circuit breakers, sulfur hexafluoride circuit breakers, solid gas generating circuit breakers, and magnetic blowing circuit breakers.
The on-off element is the core part of the circuit breaker, which completes the on and off of the main circuit. The on-off of the main circuit is transmitted to the on-off element by the intermediate transmission mechanism after the operating mechanism receives the operation instruction, and the on-off element executes the command to make the main circuit on or off. The on-off element includes contacts, conductive parts, arc extinguishing medium and arc extinguishing chamber, etc., and is generally placed on an insulating support to insulate the live part from the ground, and the insulating support is installed on the base. The structure of these basic components varies with the type of circuit breaker.
According to the nature of operation, it can be divided into: electric mechanism, pneumatic mechanism, hydraulic mechanism, spring energy storage mechanism, manual mechanism.
1. Oil circuit breaker. Using transformer oil as arc extinguishing medium, there are two types: more oil and less oil.
2. Sulfur hexafluoride circuit breaker. The inert gas sulfur hexafluoride is used to extinguish the arc, and its high insulating properties are used to enhance the insulation between the contacts.
3. Vacuum circuit breaker. The contact is sealed in a high vacuum arc extinguishing chamber, and the arc is extinguished by using the high insulation performance of the vacuum.
4. Air circuit breaker. Use high-speed compressed air to extinguish the arc.
5. Solid gas production circuit breaker. The arc is extinguished by using the gas decomposed by the solid gas-producing material under the action of the high temperature of the arc.
6. Magnetic blower circuit breaker. When the circuit is broken, the electromagnetic force generated by the large current flowing through itself is used to quickly elongate the arc and suck it into the magnetic arc extinguishing chamber for cooling and extinguishing.
1) It can cut off or close the no-load current of high-voltage lines.
2) It can cut off and close the load current of the high-voltage line.
3) It can cut off and close the fault current of the high voltage line.
4) Cooperate with the relay protection, it can quickly remove the fault and ensure the safe operation of the system.