A Model Predictive Control Strategy for Modular DAB Converter of an Input-Series Output-Parallel Solid-State Transformer

Solid-state transformers (SST) have been identified as key devices for future electrical grids that require the participation of distributed generation, electric vehicles, and energy storage in the electrical grid. Research on this subject has investigated functionalities of SST, such as power factor compensation in the public grid, precise regulation of output voltage, harmonic mitigation, short-circuit current limitation, and voltage drop immunity. This article investigates an independent model predictive control strategy used in the DC-DC stage of a SST with an Input-Series Output-Parallel (ISOP) topology, employing two DAB converters. To evaluate the topology, a small-scale prototype was constructed. The results demonstrate the feasibility of MPC control and modular strategies for the converters, including load distribution, processing time for voltage and current control, and the behavior of the Low Voltage DC bus during load changes.