A DC current limiter

Abstract

The present invention discloses a novel direct current limiter which comprises a current limiting inductor, a current limiting resistor, a parallel resistor and a current limiter branch circuit breaker. When a direct current transmission line is normally operated, the current limiting inductor can be used as a smoothing reactor. When the direct current transmission line has a short-circuit fault, the direct current limiter will limit an increase speed of a short-circuit current. When a value of the short-circuit current exceeds a security threshold value, the current limiting resistor is connected into the transmission line so as to reduce the amplitude of the short-circuit current; then re-closing is carried out, and if re-closing succeeds, the branch circuit breaker is re-closed; and if re-closing does not succeed, the branch circuit breaker is disconnected, and the fault line stops so as to prevent the short-circuit fault from causing adverse affects on other electric power apparatus, power supply system and the like. The present invention also discloses a value-taking rule of parameters of various modules in the current limiter in order to enable the novel direct current limiter to achieve an optimal operation effect in actual practice.

Description

technical field [0001] The invention belongs to the technical field of short-circuit current limiting protection of a DC power supply system, and more specifically relates to a DC current limiter. Background technique [0002] Due to the characteristics of the reverse distribution of primary energy and load demand in my country, it is objectively required to optimize the allocation of energy in a wide range. Due to its technical advantages, high-voltage direct current transmission technology has become an important means to solve long-distance cross-regional power transmission. Following the power transmission projects in the Three Gorges area and the west-to-east power transmission projects, power transmission projects such as Fufeng UHV DC and Debao DC have been put into operation one after another, and several UHV DC power transmission projects have entered the planning and design stage. [0003] However, due to the relatively low damping of the DC power supply system, c...

AI Technical Summary

Problems solved by technology

In some cases, the quench recovery time is as long as several seconds, which cannot meet the requirements of the DC power supply system;

[0006] (2) Problems such as heat generation, overvoltage, insulation level drop, increased mechanical stress, and rapid expansion of cooling medium after quench have no good solutions so far;

[0008] Since the above problems cannot be solved, the resistive superconducting DC current limiter still cannot be widely used at present.

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