Phase Parameter Measurement Method of Asymmetric AC Transmission Line Based on Distributed Parameter Model

Abstract

The invention relates to a distribution-parameter-model-based asymmetrical alternating current transmission line phase parameter precisely measuring method. The method comprises the following steps: synchronously measuring the phase voltage and the phase current at the front end and the tail end of the three phases of asymmetrical transmission lines; using the synchronous time service function of the GPS technology to realize the synchronizing sampling of voltage and current; based on the asymmetrical power transmission line model for distribution parameters, obtaining a corresponding differential equation group; and then obtaining eighteen phase parameters including the resistance, inductance and capacitance of the asymmetrical transmission lines through the measurement manner and the calculation method. The method is mostly suitable for the phase parameter measurement of a non-position shifting or partially position shifting power transmission line, can achieve high measurement accuracy and can meet the requirement for actual engineering measurement.

Description

technical field [0001] The invention relates to an accurate measurement method for phase parameters of an AC transmission line, in particular to an accurate measurement method for an asymmetrical AC line phase parameter. Background technique [0002] The transmission line is an important part of the power system and the carrier of electric energy transmission. Transmission line parameters are important parameters for power flow calculations and short-circuit calculations, as well as important references for relay protection setting and fault location. Obtaining high-precision line parameter data is of great significance to the stable operation of the power grid. [0003] In the process of erecting the actual line, it is difficult to completely transpose the transmission line. Usually, the AC line is not transposed or not completely transposed. Due to the non-transposition of the line, the three-phase line needs to be considered separately in the measurement process. phase ...

AI Technical Summary

Problems solved by technology

[0005] The present invention mainly solves the drawbacks in the prior art that cannot be used for phase parameter measurement of long-distance (200km and above) transmission lines due to the use of concentrated parameters and ignores the distributed capacitance, and also avoids the existing measurement method due to the assumption that the line is completely transposed The technical problem that leads to the oversimplification of the parameters, which makes the measurement error too large; provides a measurement method, which is not only suitable for the measurement of the phase parameters of the short-distance asymmetrical line, but also suitable for the measurement of the phase parameters of the long-distance asymmetrical transmission line. Measure a total of 18 phase parameters including resistance, inductance and capacitance at one time

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