Method for measuring phase self-admittance and phase self-impedance parameters of alternating-current extra-high voltage same-tower double-circuit lines

Abstract

The invention discloses a method for measuring phase self-admittance and phase self-impedance parameters of alternating-current extra-high voltage same-tower double-circuit lines. The phase self-admittance measurement method includes the following steps that (1) the head end and the tail end of a phase to be measured are in an open state, and the head ends and the tail ends of other phases not to be measured are short-circuited over the ground; (2) alternating-current voltage is applied to the head end of the phase to be measured, the head end and the tail end of the phase are synchronously measured to obtain head end voltage, head end currents, tail end voltage and tail end currents of the phase to be measured, and the time error of synchronous measurement of the head end and the tail end of the phase to be measured is smaller than 1 microsecond; (3) self-admittance is obtained according to a formula. A traditional measurement method is changed, distribution parameter characteristics of a wiring mode and an algorithm, influences of other phases on the phase to be measured and existence of power frequency interference are considered, especially in a long-distance electric transmission and distribution circuit, errors of self parameters measured in the method are reduced and requirements of a project are met.

Description

technical field [0001] The invention belongs to power transmission and transformation testing, in particular to a method for measuring phase self-admittance and phase self-impedance parameters of an AC ultra-high voltage double-circuit line on the same tower. Background technique [0002] For the measurement of phase self-impedance and self-admittance of long-distance UHV AC double-circuit lines on the same tower, the simple measurement method is directly obtained by dividing the head-end voltage by the head-end current and dividing the head-end current by the head-end voltage. The characteristics of wire distribution parameters and the existence of power frequency interference often produce large errors. The longer the line distance is, the greater the error is. This kind of error may not be tolerated in engineering applications, so it is not suitable for the measurement of long-distance line phase parameters. . The wiring mode of each phase during the measurement process ...

AI Technical Summary

Problems solved by technology

[0003] The purpose of the present invention is to propose a technical scheme for measuring the phase self-admittance and phase self-impedance parameters of AC UHV double-circuit lines on the same tower in response to the above problems. For the problem of power frequency interference, the long-line equation is solved by using the voltage and current measured simultaneously at both ends to overcome the mutual influence of capacitance and impedance. This method is applicable to the measurement of phase parameters of lines with different lengths

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