Novel quick-response direct-current current limiter and current limiting method

Abstract

The invention relates to a novel quick-response direct-current current limiter and a current limiting method. Through additionally arranging an auxiliary branch circuit to a right iron core column ofa traditional two-column saturated iron core type direct-current current limiter, the negative effect of prolonging the fault current drop time of an original current limiter when a direct-current circuit breaker fails and is broken is eliminated, the breaking process is accelerated, the energy absorption stress of the circuit breaker is reduced, the overvoltage stress is reduced, the response speed is accelerated, and the insulation cost is reduced.

Description

technical field [0001] The invention relates to a magnetically saturated iron core type DC fault current limiter and a current limiting method, in particular to a novel fast-response DC current limiter and a current limiting method. Background technique [0002] The rapid rise of the fault current in the HVDC system has been threatening the safe operation of the HVDC system. Therefore, a fault current limiter that limits the rising speed of the fault current is essential for the safe operation of the system. The structure diagram of the existing traditional magnetic saturation type DC fault current limiter is as follows: figure 1 , A variable inductance is generated by embedding a permanent magnet in the iron core. The magnetic field direction of the permanent magnet is opposite to the magnetic field direction generated by the DC current in the coil. The magnetic field of the permanent magnet makes the iron core in a magnetic saturation state. When working normally, the mag...

AI Technical Summary

Problems solved by technology

When a short-circuit fault occurs, the magnetic flux generated by the large current is sufficient to offset the magnetic flux of the permanent magnet, the iron core is out of saturation, and high inductance is rapidly generated in the DC coil, thereby limiting the rising speed of the short-circuit current

However, when the existing traditional magnetically saturated core-type DC fault current limiter is used with a DC circuit breaker, it will cause the circuit breaker to withstand a large overvoltage and absorb energy, which increases the manufacturing cost of the circuit breaker.

And seriously suppress the fault current drop rate, prolong the time for the fault current to act on the power system, and cause damage to related power equipment

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