Power analysis of thyristor-regulated reactor with fully controlled semiconductor valves

Abstract

Flexible AC transmission systems that are built by using modern advances in power electronics are key components of smart grids. The object of research is a thyristor-controlled reactor, which is used as part of a static reactive power compensator to control the reactive power in the transmission and distribution electrical networks of power supply systems. It is proposed to use two-operation semiconductor gates in the regulator, which made it possible to obtain qualitatively new adjusting properties. The analysis of reactor power under the mode of phase control of the conductive state of gates by setting the moments of their closing time was carried out. Analytical expressions for angular power characteristics of the main harmonic were derived. It was revealed that by regulating, based on the phase principle, the conductive state of ideal semiconductor gates, which are switched on in series with ideal inductance, along with the adjustment of reactive power, the phenomenon of consumption of active power from the grid at the main harmonic is observed. It is shown that the reason for this is artificially obtained, with the help of semiconductor gates, active-inductive nature of the angle of displacement of the main harmonic of the current in the reactor relative to the voltage of the power supply. The study results prove the effect of adjusting the active power by a thyristor-regulated reactor. Research involving a virtual model illustrated the adjustment of the active power component of a synchronous generator by the effect on the rotor speed during gate adjustment of reactor power. The active power resource obtained in the process of thyristor adjustment of the reactor is commensurate with its installed capacity