Finite Control Set - Model Predictive Control With Improved Harmonic Rejection Applied To Multi-Cell Afe Rectifier

A control scheme based on finite control set - model predictive (FCS-MPC) improved with a Feedback Quantizer is presented. The FCS-MPC is a control scheme popularly used in power converters because, among others, (i) the nonlinearities and constraints of the converter's operation, are quickly considering, (ii) it uses the natural discrete operation of power converters, and (iii) the rapid response to changes in both references or disturbances. However, the variable switching frequency operation in model-based predictive control results in a spread harmonic spectrum, generating resonances or saturation in input transformers when used in active front-end (AFE) rectifiers. This paper proposes an improved FCS-MPC, using a feedback Quantizer applied in a multi-cell AFE rectifier. This above consists of a feedback modulation technique, which allows minimizing the low-frequency harmonics in the converter PWM voltage. Simulation results verify the performance of the proposal obtaining improved harmonic spectrum of both input current and PWM voltage waveforms of the converter.