Dynamic characteristics research of electric output in the curcuit with thyristor voltage regulator supplying the synchronous motor

Abstract

Societal development is followed by increasing consumption of electrical energy. Sharp increase of energy consumption is conditioned by escalation of production and technological advancement. The number of industrial consumers is rising, most of which are non-linear, non-symmetrical and ever-changing. Primarily they are semiconductor converters of high power capacity. These are thyristor converters and thyristor regulators. Thyristor voltage regulators are widespread in different production spheres. Mostly they are used as soft start devices for synchronous and asynchronous machines. Thyristor transducers and thyristor voltage regulators are used to control the modes of electrical installations as well. Higher harmonics emerge during thyristor converter’s operation. These upper harmonics can cause overheating and breakdown of neutral conductors, false starts of fuses and automatic switches, accelerated aging of wires and cables, additional power losses in transformers, distortion of voltage sine wave, premature wear and failure of capacitors in power compensation installations, failures of computer and telecommunication hardware, lower power factor of electrical installations and incorrect metering. Proper evaluation of electrical energy quality is one of the most important problems for industrial enterprises in the conditions of modern technological advancement. The up-to-date standard which declares the order of evaluating electrical power components is IEEE 1459-2010 standard. The standard provides the definitions used for measuring electric power quantities under sinusoidal, non-sinusoidal, balanced, or unbalanced conditions. The mathematical expressions used in the past are listed, as well as the new expressions, and the explanations of the new definitions features