Ground electric field measurement system for AC/DC parallel powerline and measurement method thereof

Abstract

The invention relates to a system and a method for measuring ground electric field of AC / DC parallel transmission lines, which belongs to the technical field of high voltage transmission line electromagnetic environment. The system mainly comprises sequentially connected rotary voltmeter, an oscilloscope, and a computer for storing mixed electric field analytic program; and the method comprises the following steps: reading calibration data of the rotary voltmeter; setting sampling frequency of the oscilloscope; carrying out frequency spectral analysis on sampled data and searching peak frequency; analyzing the peak frequency to judge fundamental frequency, difference frequency and multiple frequency; calculating an amplitude value of each fundamental frequency external electric field; and storing external electric field frequency spectrum information. The method successfully measures AC / DC mixed electric field by adopting the system for measuring the ground electric field of the AC / DC parallel transmission lines and has higher measuring accuracy.

Description

technical field [0001] The invention belongs to the technical field of electromagnetic environment of high-voltage transmission lines, and in particular relates to the development of a ground electric field measurement system under AC-DC parallel high-voltage transmission lines. Background technique [0002] With the rapid development of my country's power system construction, there are more and more applications of AC-DC parallel transmission in power transmission-intensive areas such as power stations and substations. Especially in the construction of the UHV DC power grid, on the one hand, the DC and AC lines near the converter station exit converge in one place, and the possible paths may be the same. Setting up the AC and DC lines next to each other or even sharing the same corridor can save a lot of land and reduce the difficulty of design; On the other hand, if the newly added long-distance cross-regional DC transmission lines can share the existing AC transmission co...

AI Technical Summary

Problems solved by technology

At present, the measurement device for the above physical quantities is only suitable for a separate DC line or AC line. If it is directly applied to an AC-DC parallel line, it may be difficult to obtain the real value because the AC and DC cannot be taken into account, or the effects caused by the AC and DC cannot be distinguished. source of pollution

[0004] The principle of the ground electric field measurement device under the AC and DC lines is different. If different devices are used to measure the AC and DC components respectively, it cannot be guaranteed that the measured AC field and DC field are at the same position; The linear effect may produce a non-DC or power frequency AC electric field. Using traditional measurement methods will inevitably ignore this part of the electric field and affect the measurement accuracy

Images