ZPUC-MMC: Real-Time Implementation with Model Predictive Control

With reduced number of components count, Modular Multilevel Converter (MMC) based on ZPUC converter can generate a higher number of voltage levels when compared to well-known topologies. However, the capacitors voltage balancing of ZPUC topology remains a challenge when operating as a submodule due to the high number of capacitor’s voltages to be regulated at the same time in each submodule. This becomes more complicated when several submodules operate and when no self voltage balancing can be achieved such the case of seven-level ZPUC (7L-ZPUC) converter. For this reason, Model Predictive Control (MPC), well known of its superiority in achieving multiple control objectives and superior dynamic performance is introduced in this paper as a controller for the MMC converter based 7L-ZPUC. A Finite Set Model Predictive Control method (FS-MPC) is designed to control a three-phase grid-connected MMC. The proposed FS-MPC is designed to generate thirteen-level output phase voltage and 25-level line-to-line voltages. A detailed real-time model of the converter and its suggested controller is developed and implemented in the real-time simulation software Hypersim to validate the effectiveness of the proposed predictive control. Real-time implementation results verify and demonstrate the good performance of the overall Software In the Loop (SIL) application.