Fast periodic steady state solution of systems containing thyristor switched capacitors

In this paper, a novel, efficient and simple single-phase model of the thyristor switched capacitor (TSC) is presented. Its dynamic behaviour is described by a set of ordinary differential equations (ODEs) in the time domain. The periodic steady-state solution of electric systems containing this type of static VAr compensators is efficiently obtained with the application of two Newton techniques for the acceleration of time domain computations to the limit cycle. A comparative analysis between the periodic steady-state solutions obtained with the conventional brute force (BF) procedure and the Newton methods (numerical differentiation and direct approach, respectively) is presented in terms of total number of cycles and CPU times required to reach the limit cycle. An harmonic analysis is presented in order to analyze the harmonic distortion produced by the TSC's operation.