Bidirectional current-limiting DC current limiter

Abstract

The invention discloses a bidirectional current-limiting DC current limiter, and the current limiter comprises an input end, a current-limiting branch, a current conversion branch and an output end; the commutation branch comprises an external circuit commutation branch and an internal circuit commutation branch. When the bidirectional current-limiting DC current limiter is in an on-state, the bidirectional current-limiting DC current limiter is connected in series with a DC line, and when a fault occurs, current limiting can be instantaneously put into use, so the system instability caused by rapid current rise at the beginning of the fault is avoided; meanwhile, the bidirectional current-limiting DC current limiter realizes bidirectional current limiting of the current limiter through four diodes, and the system mainly adopts the diodes and IGBTs as switching devices, so that the cost is relatively low, and the investment is relatively saved; besides, the bidirectional current-limiting DC current limiter realizes the conversion of DC current into high-frequency AC current by controlling the alternative conduction of the IGBT, and can control the disconnection of the DC circuit breaker especially when the current is close to 0, thereby greatly improving the disconnection reliability of the DC circuit breaker and reducing the removal capacity of the DC circuit breaker.

Description

technical field [0001] The invention relates to the technical field of current limiters, in particular to a bidirectional current limiting DC current limiter. Background technique [0002] Current DC current limiters mainly include solid-state current limiters and superconducting current limiters. The superconducting current limiter uses the physical properties of superconductors to automatically quench when the current rises sharply. The fault signal immediately connects a resistor or inductor in series in the fault circuit through the action of the power electronic device, thereby preventing the fault current from rising further. [0003] Both of the above two current limiters have inherent weaknesses: In order to meet the high voltage and large power requirements, solid-state current limiters often require a large number of devices to be connected in series and parallel, which will cause on-state loss, which will lead to economic decline; the manufacturing cost of superc...

AI Technical Summary

Problems solved by technology

[0005] The invention provides a bidirectional current-limiting DC current limiter, which can meet the requirements of low manufacturing cost, small equipment size, and overcome the problem of economical decline as much as possible.

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