Analysis experimental device and analysis experimental method for protection malfunction caused by direct current (DC) grounding cause

Abstract

The invention discloses an analysis experimental device and an analysis experimental method for protection malfunction caused by direct current (DC) grounding. The analysis experimental device stimulates the circuit sate of a DC system in actual operation, provides experimental parameters such as insulation resistance, bridge resistance, grounding capacitance, cable capacitance and the like, and can be used for experimenting on faults of positive grounding, negative grounding and control loop grounding; concrete experimental contents and a concrete experimental method are provided; and a principle of protection malfunction caused by one-point grounding and related parameters thereof are fully realized for research and development, production, inspection, operation and maintenance and other links so as to take protection measures to prevent the generation of protection malfunction accidents caused by one-point grounding, thereby effectively improving the safe operation level of an electric system. The experimental method can be widely applied in relay protection research and production manufacturers, DC grounding detection equipment research and production manufacturers and operation accident analysis on the electric system.

Description

technical field [0001] The invention relates to the technical field of DC systems and relay protection, in particular to an experimental device and method for analyzing protection malfunctions caused by DC grounding. Background technique [0002] The DC system provides working power for control equipment such as relay protection of the power system. In order to improve the reliability of power supply, it is set as an ungrounded system, that is, a one-point ground fault is allowed to operate for a short time. , When a little ground fault occurs, it must be dealt with within 24 hours, that is, the ground fault point is eliminated, and the DC system returns to normal. [0003] In the past 10 years, great changes have taken place in the technologies used in DC systems and protection and control equipment. For example, the operating power of the control loop has decreased, the DC system has a large capacitance to the ground, and the control cable also has capacitance to the groun...

AI Technical Summary

Problems solved by technology

[0003] In the past 10 years, great changes have taken place in the technologies used in DC systems and protection and control equipment. For example, the operating power of the control loop has decreased, the DC system has a large capacitance to the ground, and the control cable also has capacitance to the ground. Faults, under certain conditions, cause protection to malfunction

Many literatures have also reported this kind of protection misoperation accident, but because there is no corresponding test equipment to analyze, test and evaluate the phenomenon of protection misoperation caused by ground fault, it is difficult to take corresponding measures to prevent the occurrence of such accidents, resulting in the current power The system still often has ground faults that cause protection misoperation accidents, which seriously endanger the safe and stable operation of the power system.

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