Transfer entropy-based multi-terminal DC transmission line protection method

Abstract

The invention discloses a transfer entropy-based multi-terminal DC transmission line protection method, which comprises the following steps of (S1) collecting positive and negative current of a multi-terminal DC transmission line on a DC circuit breaker of a fault point; (S2) calculating a transfer entropy drop of the positive and negative current; (S3) judging whether a fault appears or not according to the transfer entropy drop and a transfer entropy criterion; (S4) calculating zero-module current on the DC circuit breaker of the fault point by using current decoupling, and carrying out fault judgment according to the zero-module current and a fault pole selection criterion to obtain the fault type; (S5) finding out a fault pole according to the fault type, collecting a current signal ofthe fault pole and calculating a Kurtosis factor; and (S6) judging whether the fault appears in the line or not according to the Kurtosis factor and a Kurtosis factor criterion. According to the transfer entropy-based multi-terminal DC transmission line protection method, the problems of low practicability, a complicated system structure and a poor fault identification effect and the problem thatprotection cannot be carried out in an offline state in the prior art are solved.

Description

technical field [0001] The invention relates to the technical field of line protection, in particular to a method for protecting multi-terminal DC transmission lines based on transfer entropy. Background technique [0002] In the 1990s, the voltage source converter type high-voltage direct current transmission (VSC-HVDC) based on fully controlled devices developed rapidly. The emergence of VSC technology has also promoted the development of multi-terminal direct current transmission (MTDC), but the current two-level VSC and half-bridge modular multilevel converter (MMC) in multi-terminal direct current system engineering are more sensitive to DC line faults. Fault-induced voltage drops that cause overcurrent in insulated-gate bipolar transistors (IGBTs) may have more serious consequences. [0003] The development of multi-terminal DC transmission technology also makes the research of its protection scheme particularly important, but the accurate and selective removal of fau...

AI Technical Summary

Problems solved by technology

[0009] Aiming at the above-mentioned deficiencies in the prior art, the present invention provides a multi-terminal direct current transmission line protection method based on transfer entropy with high practicability, simple system structure, accurate fault identification effect and high timeliness, and guarantees protection in offline state The implementation of the existing technology solves the problems of low practicability, complex system structure, inability to protect in an offline state, and poor fault identification effect in the existing technology

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