ABB high voltage circuit breaker AB high voltage circuit breaker loose our technology has made great progress, mainly in: 1) developed PM type 145242kV80kA single break compressor tank 5 dagger breaker; 2) 5 "short circuit 6 generator circuit breaker breaking current up to 200kA, developed a HEC7/ type 8 rated voltage 30/25ICV, rated current 24OOA (natural cooling) and 38OOA (forced air cooling), rated short-circuit breaking current 160/200ICA 5 generator circuit breaker; 3) break through the traditional manufacturing medium voltage circuit breaker, with permanent magnetic actuator for vacuum circuit breaker and 80kASF6 tank type circuit breaker using the same component to reduce the cost of ABB company using the research and development of 80kA single break interrupter, developed PM type 145 and 245kV80kA gas tank type circuit breaker. Among them, the PMG type 80kA circuit breaker is three phase operation, and the PM1 type is single phase operation.
The 80kA circuit breaker can use parts of the 63kA circuit breaker, which has been produced in large quantities and has been actually tested in operation. The difference between the two is only in the arc extinguishing chamber and the inner casing connected to the arc extinguishing chamber.
The two type of arc extinguishing chamber can use the same operating mechanism and the same connecting rod, because the 80kA arc extinguishing chamber does not need to increase much work work. The area of the piston and cylinder has not changed.
The 63kA and 80kA arc extinguishing chamber work at the same pressure rise limit value and the same opening stroke. So the compression work of the same "; the difference is the kinetic energy head quality increases slightly, arcing contacts only increased a few millimeters, and open the speed is constant, the total energy supplied by the actuator (SFft gas compression work, kinetic energy and friction loss and) despite a slight increase, but still in the 242PMG type current. The dynamic mechanism of operation power within. 80kA and 63kA circuit breaker can be improved in the same arc extinguishing chamber nozzle in the newly designed 80kA arc extinguishing chamber, two areas need to be improved. First, the nozzle passageway must be redesigned to meet the higher transient recovery voltage under 245kV. The second is that the shell of the interrupter chamber must accommodate and cool the hot gas discharged when 80kA fails. The company has developed a modified nozzle by using the impact characteristic curve experiment and the completely modern computing software.
During the opening and breaking process, the nozzle sprayed hot gas in two directions. The task of the movable and static contact shell is to accept the heat and mix it with the cold air and return to the gas tank. The increase of the energy and volume of the exhaust gas is proportional to the fault current. Therefore, the capacity of the shell of the 80kA arc extinguishing chamber must be equivalent to 1.6 times that of the 63kA arc extinguishing chamber.
Add an external capacitor to a 10nF capacitor. The 80kA circuit breaker must increase the capacitance to 30nF. and the busbar needs 15F capacitance. The external capacitor is quite large. But in order to minimize its size and weight, the 15nF and 30nF components are installed in the shell of the composite material. It can be mounted directly to any of the sleeves, thus eliminating a single base and a capacitor bracket.
Large current generator circuit breaker SF6 ABB company since 1980s, has made unremitting efforts, the SF6 generator circuit breaker is bigger and stronger, to achieve 24kV, rated current 12000A, short circuit current 100kA, after reaching 3 of rated voltage 0/25kV, rated current 24000A (natural cooling) 38000A (forced air cooling), rated short-circuit breaking current up to 160/200kA, SF6 generator circuit breaker is the current highest parameters. It can meet the rated capacity of a generator with a capacity of 1 million 500 thousand kW.
The 250kA generator protects the compressed air circuit breaker. In 1985, a SF6 circuit breaker for 24kV12000A100kA generator protection was developed. The company replaced the DR type compressed air circuit breaker with a HEC7/8 type SF6 circuit breaker with short circuit breaking current approaching the DR air circuit breaker. The DR type compressed air circuit breaker is no longer produced. The company's HEC type motor 36 circuit breakers form a series. Rated voltage 25kV/30kV, rated current 130002400038000A, rated short-circuit open circuit breaker arc extinguishing, self energized arc extinguishing principle, meaning that the power needed for arc blowing is supplied by arc itself. The energy released when the arc is formed makes the local pressure rise and the temperature increase sharply. Another factor to increase the pressure is the effect of magnetic contraction in the arc. The magnetic force produced by the current, in turn, precipitates a powerful longitudinal plasma jet from the arc, which is ejected outward and partly into the heat volume.
The circuit breaker has two contact systems, one for carrying the working current and the other for the arc contact system.
The design of the data transmission mechanism of the generator circuit breaker ABB of TT schedule is made at electric time, so that the rated current contact system opens before a few seconds of the arcing contact system, and makes sure that the full contact current is borne and disconnected by the arcing contact. The opening arc produced when the arc contact is opened is extinguished when the large current is over zero. When small current is small, it is not enough to establish the pressure needed for automatic arc blowing. At this point the concentric pressure piston plays a role, which helps to establish pressure in the heat volume and thus successfully extinguish the arc.
The arc contact system is the key. Because the system must be competent for the instantaneous peak current to 600kA, a series of criteria must be met. The arc contact consists of the touch finger.
The matrix part is an elastic copper alloy (CuCrZr), and the tip of the arc is a copper - tungsten tungsten composite. The matrix and the junction of the tip are also copper.
The heating design of the circuit breaker is based on the assumption that the highest temperature of silver plated contact can reach L5 degree C. under the condition that the ambient temperature is 40 degrees C, and the temperature of other contact components is not more than 70 degrees C (under some circumstances 8 (TC).
The advantage of a closed structure is that the shell not only encircle the inner conductor but also encircle the external current path. Because the current is in the case of 180 degree reverse phase, the external field strength