Short-circuit current suppression device based on phase change resistor

Abstract

The invention relates to a short-circuit current suppression device based on a phase-change resistor, the device comprises the phase-change resistor connected in series on a distribution line, the phase-change resistor comprises a phase-change layer and an electrode, and the electrode is connected with a pulse signal, and the device has the advantages that the phase-change resistor is connected in series on the distribution line and comprises the phase-change layer, the phase change layer is easy to realize conversion from a crystalline state to an amorphous state, so that the resistance of the phase change resistor is changed, the current of the distribution line is changed, the short-circuit level of the distribution line can be effectively reduced, the damage of the heat effect and the electrodynamic effect of short-circuit current to distribution equipment is reduced; the requirement on the breaking capacity of a circuit breaker can be reduced, the voltage sag degree caused by a short-circuit fault can be reduced before a fault loop of the circuit breaker is cut off, the power utilization continuity of a sensitive load is improved, and economic loss brought to a user is reduced.

Description

technical field [0001] The invention relates to a short-circuit current suppression device based on phase-change resistance. Background technique [0002] The distribution network is an important part of the power system. In the entire power system, the distribution network has the largest scale, the widest distribution and the most diversity. Its high-quality and reliable continuous power supply greatly affects the quality of power consumption of users and social economy. Coordinated development and social harmony. The occurrence of faults destroys the normal operation of the power grid, and the most influential ones are various short-circuit faults. In recent years, with the continuous increase of power supply load, the power system has gradually changed the previous isolated operation mode, and the close interconnection of major power grids has increased the short-circuit current, which has greatly affected the safe and stable operation of the power grid. impact, and th...

AI Technical Summary

Problems solved by technology

A large short-circuit current will cause a large amount of heat to be generated by the power distribution equipment. When the heat cannot be dissipated in time, the equipment may be damaged or even burned due to high temperature; It will generate extremely strong electric power, which will cause great impact damage to the equipment;

[0005] (2) Excessive short-circuit current is not good for breaking the circuit breaker;

[0006] (3) Cause losses to users: short-circuit faults cause voltage sags, affect the continuity of power consumption of sensitive loads, and bring economic losses to users

[0008] (1) Superconducting fault current limiter: the current is less than the superconducting critical current during normal operation, so the voltage drop of the superconducting material is close to zero, and the system loss is also very small. When the fault current level exceeds a certain threshold, the short-circuit current is controlled by the superconducting The conductive part is transferred to the non-superconducting part, the heat generation causes the superconductor to be in a quench state, the current limiting / current unit quickly becomes a high impedance state, and the fault current can be effectively suppressed, but the superconducting fault current limiter must be equipped with a large capacity cooling unit

[0009] (2) Magnetically controlled fault current limiter: use the saturated and unsaturated state switching of the current limiter core to realize short-circuit current limitation. The traditional winding magnetic saturation fault current limiter has relatively large steady-state operating loss, which may affect power transmission. The normal operation of the line, and the DC bias capability of the DC bias winding is highly required

The fault current limiter only consists of a fast switch and a reactor. It has simple structure, mature technology, low manufacturing cost, close to zero operating loss, and small footprint. The disadvantage is that the fast switch has a large breaking current and cannot be quickly reset after the fault is cleared.

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