Shunt inductance current-limiting breaker

Abstract

The invention discloses a parallel inductance current-limiting circuit breaker, in particular to a high-capacity protection device of short-circuit fault, belonging to the protection device of short-circuit fault in electric power system, which comprises a plurality of parallel coils, a plurality of protective resistances, an auxiliary circuit breaker and a main circuit breaker. The ends of the first coil are connected with the contrary ends of the second coil and the coupling coefficient is 1. The first coil is connected in parallel with the first protective resistance, and then is connectedin series with the auxiliary circuit breaker. The second coil is connected in parallel with the second protective resistance, and then is connected in series with the main circuit breaker. The whole device is connected in series with the main system. When the control circuit detects the short-circuit fault in the main system, the control signal is sent, the auxiliary circuit breaker is switched on first and is connected in parallel with the inductance for decoupling, so the fault current is limited to a certain level, and then the main circuit breaker is switched on, so the fault current is completely cut off. The invention aims at overcoming the shortcoming of insufficient breaking capacity of prior circuit breakers, improving the breaking capacity and effectively cutting off fault current. The invention has the advantages of low loss, low operating cost, and ability of significantly improving the breaking capacity of the circuit breaker and effectively cutting the fault current off.

Description

technical field [0001] The invention belongs to a short-circuit fault protection device of an electric power system, in particular to a large-capacity short-circuit fault protection device to improve the breaking capacity of a circuit breaker and ensure that it can effectively cut off the fault current. Background technique [0002] With the development of technology and economy, the power system is continuously expanding its scale through self-expansion and Internet interconnection, and the system capacity and short-circuit current of the power transmission and distribution network increase accordingly. As the short-circuit current increases, the negative impact on the system and users will increase, and the requirements for the electrical and thermal stability parameters of the power equipment will be higher; the increase in the short-circuit capacity may also cause the circuit breaker to fail to cut off the short-circuit current effectively in time, thus Adverse effects o...

AI Technical Summary

Problems solved by technology

The above measures limit the level of short-circuit current to varying degrees, but they all have their own defects and deficiencies, or have adverse effects on the power grid in another form, or are technically difficult to implement (large-capacity circuit breakers)

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