A system and method for removing short-circuit faults of a transformer-type high-voltage direct current circuit breaker

Abstract

The invention discloses a system and method for removing short-circuit faults of a transformer-type high-voltage direct current circuit breaker, including an inner loop to regulate the control current and an outer loop to regulate the control voltage. Transformation and protection control. The auxiliary controller of the present invention detects the zero value of the duty cycle. When the zero value is detected, the fault state is judged, the selection switch operation is performed, and the line is cut off until the fault is eliminated and the zero value detector detects the duty cycle. If the ratio is not zero, it can be judged to be in a normal state and not act. In this way, through the detection and adjustment of the duty ratio, the function of the circuit breaker can be realized, and the short-circuit fault can be removed in a timely and effective manner, which has the advantage of short response time.

Description

Technical field [0001] The invention relates to a high-voltage direct current transmission protection system, in particular to a system and method for removing short-circuit faults of a variable voltage high-voltage direct current circuit breaker. Background technique [0002] In the high-voltage AC power transmission system, the normal input and accident removal of the transmission line is realized by the high-voltage AC circuit breaker. In the high-voltage direct current transmission system, the converter valve control (gate) pole control is used to eliminate temporary faults or mechanical high-voltage circuit breakers are used for removal when a short-circuit fault occurs. However, with the development of VSC-HVDC transmission technology Development and application, due to the long response time of mechanical high-voltage DC circuit breakers, it is difficult to meet the demand for rapid removal of short-circuit faults. Therefore, it is necessary to develop new fast high-volta...

AI Technical Summary

Problems solved by technology

[0003] The current mechanical high-voltage DC circuit breaker can cut off the short-circuit current within tens of milliseconds, and the cutting speed of this fault current cannot meet the requirements of the new VSC-HVDC power transmission system

Solid state circuit breakers can easily overcome the limitation of breaking speed, but they will generate a lot of losses in steady state operation

The hybrid circuit breaker combines the good static characteristics of mechanical circuit breakers and the dynamic characteristics of solid state circuit breakers without arc breaking, and has the advantages of low operating loss, long service life, high reliability and good stability, but for the manufacture of fast switch The requirements are very high, and the breaking time is still affected by the fast switch and the protection system and communication time

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