Sampling resistor sensor for extra-high-voltage corona current

Abstract

The invention relates to a sampling resistor sensor for the extra-high-voltage direct corona current. The sampling resistor sensor comprises a cylinder-shaped sampling resistor, wherein an insulation tube penetrates through the hollow part of the sampling resistor, each end of the insulation tube is fixedly connected with an insulation flange plate, two grading rings are respectively fixed on the two insulation flange plates through metal flange plates arranged at the centers of the two grading rings, one end of one metal flange plate is connected into an extra-high-voltage transmission line through a screened lead, the corona current of the extra-high-voltage transmission line is required to be measured, the other end of the metal flange plate is connected with one end of the sampling resistor through the screened lead, the other end of the sampling resistor is connected with the other metal flange plate through a screened lead, the sampling resistor is connected with a shunt resistor in parallel through a screened lead, and the shunt resistor is arranged in the insulation tube. The sampling resistor sensor can be widely used in the direct current extra-high-voltage environment with plus or minus 1200 KV (kilovolt) to the largest extent and realizes the wide-frequency-domain accurate measurement of the corona current in the extra-high-voltage transmission line.

Description

technical field [0001] The invention relates to a sampling resistance sensor, in particular to a sampling resistance sensor for measuring DC corona current in an extra-high voltage transmission line. Background technique [0002] In order to meet the increase in electricity load, improve the structure of the power grid, and implement the strategy of "power transmission from west to east, mutual supply between north and south, and national networking", it is imperative to develop UHV power grids. UHV transmission is developed on the basis of EHV transmission. It can realize long-distance and large-capacity transmission of electric energy. It is suitable for asynchronous interconnection of large-scale power grids. It has the advantages of low line cost and low power loss. Among them, the study of corona loss of transmission lines is one of the key technologies of UHVDC power transmission and transformation projects, and corona current is the most direct parameter to characteri...

AI Technical Summary

Problems solved by technology

However, the measurement frequency band of the existing sampling resistance sensor is narrow, generally lower than 2MHz, and the highest does not exceed 4.5MHZ

Moreover, in the prior art, a single non-inductive resistor is used as the sampling resistor, and the influence of distributed capacitance on the corona current measurement result is not considered

However, existing scientific studies have shown that the corona signal range covers a wide frequency band from low frequency to high frequency, and the upper limit can reach 30MHz

The existing corona current sampling sensors can no longer meet the actual needs of studying electromagnetic environments such as radio communication interference, and the lack of high-frequency band information has brought great obstacles to the complete analysis and understanding of corona phenomena.

At the same time, the application voltage range of the existing corona current measurement system is generally lower than 500KV, and the maximum does not exceed 1000KV, so it cannot be applied in UHV transmission lines

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