Circulating Current Suppression Strategy of Modular Multilevel Converter Based on Model Predictive Control

Modular Multilevel Converter (MMC) has the characteristics of high voltage level and low switching frequency. The traditional modular multilevel converter circulating current control strategy mostly adopts PI principle, parameter setting is complicated accuracy not high, process more difficult. Model predictive optimal method based on model in existing time domain. This paper proposes a Predictive Control (MPC) carrier phase-shifted pulse width modulation (PSC-PWM) to suppress current, output wave through prediction. Compared with strategy, this simple implement, does require complex tuning calculations, combines capacitor equalization obtain wave. A 7-level MMC simulation system built MATLAB / SIMLINK verify theory, comparing methods, it can be concluded that proposed calculation efficiency, good strong robustness.