Single-end electrical quantity full-line quick-acting protection method using choke coil to construct line boundary

Abstract

The invention discloses a single-end electrical quantity full-line quick-acting protection method using a choke coil to construct the line boundary, according to the topology of different power supplysystems, the choke coil is installed on the line to construct the line boundary, and then the protection criterion is constructed according to the difference of the electric quantity between the protected line area and the internal and external faults, so as to realize the single-end electric quantity full-line quick-action protection. The invention adopts choke coil to construct the boundary ofthe circuit and realizes the single-end quantity full-line quick-acting protection on the circuit without boundary element, As that method of the invention can effectively overcome the problem of lowsensitivity of the pow frequency protection of the alternating current circuit in the multi-converter, It also meets the requirements of fast operation of protection for DC lines. At the same time, itdoes not need protection coordination when applied to distribution network. Only the electrical quantity of a single end can realize the rapid identification of faults inside and outside the protection zone, and it can effectively solve the relay protection problem of a power grid including multiple converters.

Description

technical field [0001] The invention belongs to the technical field of electric power system relay protection, and in particular relates to a single-end electric quantity full-line rapid protection method using a choke coil to construct a line boundary. Background technique [0002] With the large-scale access of wind turbines and photovoltaic power sources and the large-scale application of DC power transmission and distribution, the power system presents a form with multiple converters. For the AC system, the ability of the inverter to provide short-circuit current effectively reduces the protection sensitivity; for the DC system, the vulnerability of the converter requires the protection to quickly remove the fault. At the same time, for the distribution network, the access of distributed power sources makes it a multi-source power supply system. The bidirectional flow of short-circuit current makes it difficult to cooperate with current protection. Communication is requi...

AI Technical Summary

Problems solved by technology

For the AC system, the ability of the inverter to provide short-circuit current effectively reduces the protection sensitivity; for the DC system, the vulnerability of the converter requires the protection to quickly remove the fault

At the same time, for the distribution network, the access of distributed power sources makes it a multi-source power supply system. The bidirectional flow of short-circuit current makes it difficult to cooperate with current protection. Communication is required when using double-ended differential protection and longitudinal protection. , high cost, unable to be used on a large scale

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