This paper discusses model predictive current control of doubly-fed induction generators (DFIGs) where the rotor side is connected to a voltage source inverter (VSI) via an LC filter. The electrical system (DFIG, filter, VSI) is formulated as disturbed linear time-invariant (LTI) multiple-input multiple-output (MIMO) system without constraints. For such a system, an analytical solution of the MPC problem exists which allows for high prediction horizons. By extending the electrical system by integral error feedback (IEF), steady-state accuracy of the current control problem can be achieved. Simulation results compare the control performance of the proposed MPC scheme (i) without IEF, (ii) with IEF and (iii) with IEF and the use of future references during (symmetric) grid perturbations.
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