HIGH-VOLTAGE DIRECT-CURRENT POWER-TRANSMISSION WHOLE-LINE SPEED PROTECTION METHOD BY USING DIRECT-CURRENT FILTER CURRENT

摘要

A single-terminal electric-quantity whole-line quick action protection method for identifying faults in and out of a high-voltage direct-current power-transmission line area uses an amplitude of a specific frequency electric-quantity in a single-terminal direct-current filter branch to realize discrimination of the faults in and out of the area. The protection method only needs to adopt the single-terminal electric quantity, has a low requirement for a sampling frequency. The algorithm is simple. Sensitivity is high. The method can be easily realized during engineering. The method not only has advantages that the action speed is fast, selectivity is good and reliability is high, but also the theory is completed and is easy to be adjusted. The protection method can replace current traveling-wave protection which is taken as the main protection of the direct current power transmission line. The method is especially suitable for realizing the whole-line quick action protection of the ultra/super high-voltage direct-current power-transmission line by using the single-terminal electric quantity.