Model-predictive direct power control of AC/DC converters with one step delay compensation

This paper presents a model-predictive direct power control (MPDPC) strategy for a three-phase pulse width modulation (PWM) rectifier. The controller uses a system model to predict the system behavior on each sampling interval for each voltage vector. A cost function is then used to evaluate the active and reactive power ripples, from which the vector that generates the lowest power ripple will be applied during the next sampling interval. In addition, the influence of a one-step delay in the digital implementation is investigated and this is compensated for using a predictive scheme. The main advantages of the proposed strategy are that there is no need to use a switching table for voltage vector positioning, the power ripple is reduced, and the system displays excellent steady-state and dynamic performance. The proposed MPDPC was validated both in simulation, using MATLAB/Simulink, and experimentally, with a 5 kVA laboratory AC/DC converter.