An Active Power Filter using Single-Phase NPC Converters and Predictive Control for Medium Voltage Distribution Systems

An active power filter implemented with three single-phase Neutral Point Clamped (NPC) converters is presented and analyzed. The proposed active power filter is aimed to compensate current harmonics and reactive power in three-phase medium voltage power distribution systems. A predictive control algorithm provides the switching states that ensure fast current tracking capability. To take advantage of the predictive control implementation simplicity, this paper includes useful information to replicate this implementation on similar topologies of multilevel converters. The proposed scheme presents lower line to line voltage harmonic distortion as well as an independent control in each phase, compared with the conventional three-phase NPC topology. Simulated results confirm the implementation viability of the proposed active power filter topology and associated control strategy.