Harmonic Reduction and Reactive Power Improvement using Shunt Active Power Filter And Thyristor-Controlled Reactor

An integrated method for harmonic reduction and reactive power correction is proposed based on an integrated thyristor-controlled reactor (TCR) and a shunt active power filter (SAPF). In order to control the TCR, a PI controller with a triggering alpha derived from linear firing was used. To regulate voltage and monitor current, a nonlinear APF control was developed. This paper focuses on a decoupled method of controlling, where the controlled system is divided into two loops, one fast and one slow. A linearization control was applied to the inner loop, while a nonlinear feedback control law was applied to the outer loop. Integrated compensators were introduced to both the current and voltage loops in order to eliminate steady-state errors caused by oscillation of system parameters. The total harmonic distortion of the source current is below the permissible limits imposed by several regulatory authorities, and the power factor of the supply is very close to unity. Simulated and experimental results indicate considerable reductions in harmonic distortions and compensation for reactive power.