Long Horizon, Quadratic Programming Based Model Predictive Control (MPC) for Grid Connected Modular Multilevel Converters (MMC)

Excellent control performance is a prerequisite to operate compact modular multilevel converter (MMC) designs that employ very small module capacitance values. This paper presents a novel model predictive control (MPC) scheme featuring a linear and accurate prediction model to overcome the drawbacks of comparable control schemes. The MPC is based on a modulator that determines the switching states of the individual modules to guarantee scalability of the algorithm also for MMCs with a high number of modules. The control performance of the proposed MPC scheme is evaluated with simulations and compared to a classic cascaded PI-controller scheme.