Use of the Larionov Scheme as Negative Sequence Filter of a Three-Phase Voltage System

Abstract

The paper studies the possibility of using a three-phase two-half-wave rectification circuit as a filter of symmetrical components. A review of the main technical solutions for the measurement and control of symmetrical voltage components in three-phase networks was carried out. An experimental setup has been developed to analyze the voltage signals at the input and output of the rectifier with unbalanced power supply. The relationship between the level of the output voltage of the rectifier and the magnitude of the positive sequence voltage at its input is shown. The relationship between the negative sequence voltage and the level of output voltage ripple is revealed. As a source of information about the magnitude of the negative sequence voltage, it is proposed to use the harmonic level with a frequency of 100 Hz in the pulsating voltage signal at the rectifier output. It has been experimentally determined that a three-phase rectifier circuit can be used as a negative sequence filter in those cases where a relative error of up to 4% is not critical.