A liquid metal type ceramic high-voltage variable resistance device

Abstract

The invention discloses a liquid metal type ceramic high-voltage variable resistance device, which comprises a ceramic resistance cavity, a liquid metal, a left electrode, a right electrode and a gasmedium. The left electrode and the right electrode are fixed at the left and right ends of the ceramic resistance cavity to form a sealed cavity. The ceramic resistance cavity is composed of a coarsecavity with a larger diameter and a thin cavity with a smaller diameter, which are communicated with each other. The liquid metal is filled in the ceramic resistor cavity, the liquid metal needs to beable to enter the cavity with smaller diameter and conduct the left electrode and the right electrode when the liquid metal is horizontally placed, and the liquid metal cannot fill the ceramic resistor cavity. The gas dielectric fills the remaining ceramic resistor cavity, and the gas dielectric fills the remaining ceramic resistor cavity, and the gas dielectric fills the remaining ceramic resistor cavity must have good insulation characteristics. The device is a variable impedance FCL, which is connected in series in the system circuit. In normal operation, the impedance of the system is very small, but in the event of a fault, the impedance can be rapidly increased without commutation, so that the fault can be limited before reaching the peak.

Description

technical field [0001] The invention relates to the technical field of high-voltage circuit devices, in particular to a liquid metal type ceramic high-voltage variable resistance device. Background technique [0002] With the increase of industrial and residential power consumption, the short-circuit capacity of the power system is increasing, and the corresponding maximum short-circuit current is also increasing, even exceeding the standard regulations. This puts huge pressure on the short-circuit current withstand capacity of the system equipment and the breaking capacity of the circuit breaker. Therefore, it is necessary to limit the current of the line whose short-circuit current exceeds the standard, so as to prevent the impact on the system equipment when the system fails, and avoid the failure of the circuit breaker to open. Currently, a line series current limiting reactor or a fault current limiter (Fault Current Limiter, FCL) are generally used to limit the fault ...

AI Technical Summary

Problems solved by technology

The former method will cause commutation of the fault current. During the commutation process, it will inevitably cause overvoltage and inrush current. Dealing with the two will greatly increase the complexity of the current limiter structure, and the commutation circuit itself will also be affected. Complicated, which drives up the cost

The latter method does not require commutation, but the rapid change of line element impedance requires the element to have better variable impedance characteristics. The current superconductors, positive temperature coefficient resistors, etc. are difficult to meet the requirements of industrial applications.

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