Frequency Weighted Finite Control Set MPC of Multilevel Inverter for Controlled Spectrum of Load Current

An upgraded finite control set model predictive control strategy (MPC) for a multilevel inverter is introduced in this paper. A 3-level neutral point clamped (NPC) inverter is presented. The control strategy ensures current control with a narrow spectrum and unwanted harmonics reduction. The designed model predicts system behavior for all probable switching states of the multilevel inverter and uses a cost function to generate the expected operation. This cost function is frequency weighted as it employs a discrete-time filter for current errors. The current drawn by load as well as voltage spectrum is modified by precisely designing the filter resulting in the reduction of undesirable harmonic components. The proposed strategy is corroborated by plausible simulation results. The simulation result shows a narrower load current spectrum after the addition of a 2kHz filter component in the cost function.