An Innovative Linear Susceptance Model Deploying a Thyristor Controlled Reactor with Harmonic Suppression Circuitry and Advanced Current Controller

Abstract

The Thyristor Controlled Reactor (TCR), an operative reactive power device, is controlled non-linearly in its inductive operational mode, resulting in injection of odd current harmonics. This introduces challenges regarding power quality, which necessitates conditioning of the device. In this study, the development of a continuously and linearly controlled compensating susceptance, constructed from a TCR equipped with harmonic suppression and absorption features, is presented. The series suppression circuitry incorporated within the design consists of a series RLC circuit, resonating at the frequency of the AC source. Simultaneously, the shunt absorption circuitry is specifically designed to eliminate the third and fifth harmonic current components produced by the TCR. This innovative arrangement substantially minimizes the odd harmonics generated by the TCR. In addition, an advanced current controller has been introduced, allowing the reactive current of the proposed susceptance to be linearly controlled in both inductive and capacitive modes. The proposed susceptance was designed and simulated on PSpice, utilizing a 50Hz, 220V AC source. Simulation results demonstrate that the susceptance current reaches its steady-state value within approximately 100ms. Furthermore, the susceptance current in the steady-state region is almost completely devoid of harmonics. Notably, the proposed susceptance displays remarkable linearity during its response to reactive current demands across both inductive and capacitive operational modes. This research provides a significant step forward in addressing the challenges associated with TCR power quality.