A Low-Cost Hybrid Active Power Filter for High Voltage System

A novel low-cost shunt hybrid active power filter for power quality in high voltage system is proposed in the paper. The active power filter is based on three-phase four-switch structure. An inductor is parallel in the second-side of the transform, instead of connected in the first-side of transform. An improved SVPWM is proposed according to the APF structure. A novel coordinate matrix is proposed to transform three-phase circumrotating coordinate into two-phase static coordinate. The zero vector is composed of two space voltage vectors with same breadth and contrary direction at same working time in a switch period. Simulation results confirm the validity of the proposed structure and the improved SVPWM.