Digital electric field sensor

Abstract

The invention provides a digital electric field sensor, including: an electric field induction system which converts a synthesized electric field under a high-voltage direct-current transmission line into induction current to be output to a measured signal input channel; a reference signal generation system which generates square signals having the same frequency and same phase as the induction current as reference signals to be output to a reference signal input channel; the measured signal input channel which amplifies, filters and performs AD sampling on the induction current and then outputs the induction current to a microprocessing module; the reference signal input channel used for outputting a synchronous reference signal sequence to the microprocessing module after AD sampling is performed on the reference signals; and the microprocessing module which calculates the amplitude and phase of the synthesized electric field under the high-voltage direct-current transmission line after two phase-sensitive detectors are utilized to perform phase-sensitive detection on an input discrete sequence and the synchronous reference signal sequence. The technical scheme provided by the invention can completely overcome the defects of output drift, sensing characteristic inconsistency and the like which exist in a traditional analog electric field sensor, and greatly improves measurement accuracy and reliability of long-term use.

Description

technical field [0001] The invention relates to an electric field sensor, in particular to a digital electric field sensor suitable for measuring ground synthetic electric field under a high voltage direct current transmission line. Background technique [0002] With the vigorous development of UHV transmission projects in my country, the electromagnetic environment around transmission lines has attracted increasing attention. Under the increasingly stringent environmental protection situation, the electromagnetic environment of transmission lines will become one of the important factors affecting its application and development, and it is a major technical issue that must be considered in line design and operation. Electric field strength is an important parameter of the electromagnetic environment, and its accurate detection is of great significance. [0003] The traditional analog DC electric field sensor is implemented based on the principle of a lock-in amplifier. The ...

AI Technical Summary

Problems solved by technology

However, due to human error, it is difficult to accurately adjust the phase difference to zero

The phase difference caused by human error causes the sensitivity of the sensor to be dispersed

In addition, the adjustment of the phase is realized through the sliding rheostat, and the sliding rheostat itself has drift characteristics, which will cause the drift of the phase angle after long-term use, which will cause the sensitivity of the sensor to shift and cause measurement errors

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