Novel short circuit current limiter

Abstract

The invention discloses a novel short circuit current limiter. The novel short circuit current limiter comprises a metal oxide pressure-sensitive resistor, an iron core, a winding coiling, a snap switch and a snap switch controller; the snap switch, the snap switch controller, the iron core, the winding coil and the metal oxide pressure-sensitive resistor are connected in parallel; in case of fault, the iron core and the winding coil are arranged into the system in series to generate nonlinear inductance to limit short circuit current; the snap switch is connected in series into a system line and controlled by the snap switch controller to be on or off; the metal oxide pressure-sensitive resistor provides overvoltage support when turning on and turning off the snap switch. The novel short circuit current limiter has the obvious effects that a DC biasing circuit added for enabling saturation of the iron core is avoided; the zero loss of the system under the normal state is reached; one iron core is needed in the single-phase protection of the system, and three-phase protection needs only three iron cores. The novel short circuit current limiter has the advantages of being simple in structure, convenient to operate, and reliable to work.

Description

technical field [0001] The invention relates to a current limiting device, in particular to a novel short-circuit current limiter which can limit the current when a short-circuit fault occurs in a power grid during power transmission. Background technique [0002] The gradual expansion of the scale of the power network, the continuous increase in the degree of interconnection, and the access of various large-scale power stations make the current short-circuit current level of the power network approach the upper limit of the existing circuit breaker capacity. Such problems are particularly prominent in areas with dense power loads. Conventional technical measures such as busbar segmentation, fixed series reactance, ring network separation, etc. will have a considerable negative impact on the operation of the power grid. The short-circuit current limiter has become an important means to deal with the rapid growth of short-circuit current. The short-circuit current limiter ha...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to propose a design of a novel short-circuit current limiter in view of the deficiencies in the traditional saturated iron-core type superconducting short-circuit current limiter, such as high bias coil requirements, high operating loss, large size and high cost. The short-circuit current limiter not only does not require a DC bias system, but also requires only one iron core for single-phase protection, and three iron cores for three-phase systems, which greatly reduces the cost, reduces the size and weight of the iron core and the overall

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