Circuit single-phase ground distance measurement method

A distance measurement, single-phase grounding technology, applied in the fault location and other directions, can solve the problem of low fault distance calculation accuracy, and achieve the effect of solving the influence of single-phase grounding distance protection

CN102175952AInactive Publication Date: 2011-09-07NORTH CHINA ELECTRIC POWER UNIV (BAODING) +3
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2011-09-07
Estimated Expiration
Not applicable · inactive patent

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Abstract

The invention discloses a circuit single-phase ground distance measurement method in the field of relay protection technique of the power system. In the method, the distance from a protection installation point to a ground fault point by calculating the vector difference between the phase voltage of a fault phase of the protection installation point and the fault voltage of the single-phase ground fault point can be calculated. The method has the advantages of high measurement accuracy and practical value without being influenced by the load current and the transition resistance.
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Description

technical field

[0001] The invention belongs to the technical field of electric power system relay protection, and in particular relates to a method for measuring the single-phase grounding distance of a line. Background technique

[0002] As the voltage level of the power system is getting higher and higher, how to safely, effectively and reliably improve the power transmission capacity of the transmission line is a major issue facing the current power system in our country. As the first line of defense to ensure the safety of the power grid, relay protection is of great significance to the safe, economical and stable operation of the power grid. Malfunction or refusal of relay protection will cause serious harm to the power system. When a short-circuit fault occurs on a transmission line, especially a single-phase-to-ground short-circuit fault, it is usually not a metallic fault. At this time, due to the existence of large transition resistance at the fault point, this w...

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Embodiment Construction

[0024] The preferred embodiments will be described in detail below in conjunction with the accompanying drawings. It should be emphasized that the following description is only exemplary and not intended to limit the scope of the invention and its application.

[0025] figure 2 It is a 500kV ultra-high voltage power transmission system applying the method of the invention. The system is a typical double-ended power supply system, the busbars on both sides are m and n respectively, the length of section I of transmission line is 200km, and the length of section II of transmission line is 200km. The protection applying the method of the present invention is installed at the end m of section I of the transmission line. The phase angle difference of the equivalent power sources on both sides of m and n is δ, and the amplitudes of the power sources on both sides of m and n are 1.05 times the standard unit value and 1 times the unit unit value respectively. The transmission line...