Analysis of current and voltage harmonics introduced by the drive systems of a bucket wheel excavator

Abstract

Purpose. The quality of electricity is a problem of major interest, making it necessary to analyze the factors and causes that result in the worsening of the electric energy quality. An important aspect of electricity quality is the introduction of current and voltage harmonics in the alternating current network by non-linear consumers. The paper analyzes the deforming regime introduced by the drive systems of a bucket wheel excavator within a technological line at an open pit mine. Methods. The paper presents the measurements of power quality in a laboratory experimental study and measurements of an upgraded technological line at a lignite open pit. In this sense, the present the study of a distorting regime introduced by the drive systems formed from a static frequency converter and an asynchronous motor, as well as the results of quality power measurements introduced by the drive systems in the electric network. Findings. The paper presents analysis of the voltage and current harmonics introduced in the alternating current network of static converter-asynchronous motor drive systems, which is necessary to establish the deformation factor. The values of the deforming regime are essential to obtain the harmonic compensation solutions. Originality. The originality of the paper consists in the approach to the measurements performed and the analysis of the deforming regime introduced by the electric drive systems. Practical implications. The values of the current and voltage harmonics were determined both by the laboratory measurements and by measurements made on the supply line of a bucket wheel excavator in different operating regimes.