Development of a comprehensive power quality controller for power distribution system

A comprehensive power quality controller combined with Thyristor Controlled Reactors (TCR) and Resonant Impedance Type Hybrid Active Filter (RITHAF) is proposed in this paper for power distribution system. The RITHAF topology presented in the paper is different from the conventional Active Power Filter (APF). The basic of the new RITHAF topology is to add a Fundamental Series Resonance Circuit (FSRC) in parallel with the secondary of coupling transformer of APF, in order to force the fundamental current flow through the FSRC instead of the APF or the secondary of coupling transformer. By this way, it can reduce the rating VA of the APF greatly. The TCR and the Passive Filter (PF) of the RITHAF makes a Static Var Compensator (SVC), which acts as a classic reactive power compensator for load balancing and power factor correction , while the RITHAF acts as a classic APF which eliminate the harmonics so as to raise power quality and power factor. The main circuit structure is introduced in the paper, also the operation principle and control method are analyzed. The simulation and experimental results verify the effectiveness and advantage of the comprehensive power quality controller for power distribution system.