Сomprehensive provision of standard power quality parameters in three-phase networks by the use of hybrid filter-compensating converters

Abstract

In this work the conditions of the most effective use of the developed perspective means for the solution of the actual problem of complex providing of electromagnetic compatibility in modern distribution public electricity networks are considered. This is achieved by improvement of a number of voltage quality characteristics (harmonics, asymmetry and voltage fluctuations). The simulation model of a three-phase four-wire distribution network is proposed, which allows estimating voltage quality characteristics when connecting non-linear and asymmetric loads. The simulation modeling of the operation of the specified network with certain characteristics, with different values of the power of single- and three-phase nonlinear load (rectifiers) is carried out. The simulation results showed that in modern conditions, with a high concentration of electronic equipment in the distribution network, it is not enough for each separate unit of equipment to have a built-in individual means for reducing the emission of disturbances, which ensures compliance with the requirements of the European Harmonized Standards for Electromagnetic Compatibility. Therefore, in order to solve this problem in the electricity networks it is suggested for consumers to additionally apply group electromagnetic compatibility means, including hybrid filter-compensating converters that combine functional capabilities of a regulated filter balancing device which based on an autotransformer with the zig-zag connection of windings and an active parallel power filter. The analysis of simulation results of a three-phase electric network with standard characteristics of a distribution transformer allowed to determine the ratio of power of one- and three-phase nonlinear load of consumers and linear load asymmetries in network, for which a hybrid filter-compensating converter has an advantage over the known passive group means of improving the quality of voltage and allows you to provide the quality of voltage in accordance with the norms of the international standards.