Adaptive Power Line Harmonic Detection for Active Filter Applications

The objective of this thesis research is to develop an efficient method for accurate detections of power line harmonic distortions for the control of active filters. The research has achieved its objective with four significant results. First, an adaptive power line harmonic detection method is developed, which is based on the findings of extensive research in the areas of inside and outside of power electronics controls. Second, a simple and practical formulation of the adaptive harmonic detection method is developed, which is simplified significantly from the original complex design formulations for noise cancellations. Third, vigorous verifications of effectiveness of the adaptive detection method using computer simulations are carried out, which cover the steady state operations, the dynamic operations, normal power line conditions, non-ideal supply and load conditions, etc. Fourth, experimental verifications of the accuracy of the adaptive detection method are conducted, which cover typical distorted power line conditions for normal and unbalanced operations. For illustration, this thesis presents carefully designed computer simulation and experimental case studies that cover a wide range of power line conditions.