Development and laboratory validation of an LVDC back-to-back system with residential inverter, PV, and battery-based power generation
• The system includes a grid-connected converter, residential inverter, photovoltaic (PV) source with MPPT, and battery energy storage in a low-voltage DC (LVDC) Back-to-Back (B2B) configuration. The integrated design ensures that the energy sources are coordinated and the power is managed optimally for smart microgrids and residential networks. • A robust control strategy enables smooth transitions between grid connected and islanded modes. The system ensures that the DC-link voltage is stable through the use of a bidirectional buck-boost converter which controls the power flow during charging and discharging and also ensures that the load supply is not interrupted by the variability of the PV generation. • The proposed B2B system improves power quality by minimizing voltage sags/swells, harmonic distortion, and transient fluctuations. Real-time laboratory tests are used to validate the system’s performance and the results show that the system has high energy efficiency (94–97%) and is suitable for future PV and storage expansion. This study focuses on a consumer interface unit: a low-voltage (LV) back-to-back (B2B) converter that integrates photovoltaic (PV) generation, battery storage, and possibly other DC loads and, at the same time, decouples grid connection and supply to LV consumers. The present work explores the complexities of regulating the voltage of the DC bus and managing the current. The system employs Maximum Power Point Tracking (MPPT) to optimize solar energy harvesting and utilizes a DC-DC boost converter to amplify the voltage of the PV system. This enhances the dependability, particularly for LV (AC/DC) systems. Battery storage management is accomplished by utilizing a DC-DC buck-boost converter, ensuring a consistent power supply even in the presence of solar irradiation fluctuations. The grid-connected unit and the complete power management system (PMS) were simulated in Simulink. Thorough simulations in Simulink and laboratory validations through a rapid prototyping platform, demonstrate the system’s ability to deliver stable and efficient power in both operational modes. The incorporation of sophisticated control algorithms into the existing power management framework enhances responsiveness to fluctuations in load and solar energy, ensuring peak performance under varying conditions. Additional technical improvements have been made by fine-tuning the DC-link based on the number of IGBT-legs incorporated in the converter setup. This refinement enables more accurate regulation of the voltage levels, reducing switching losses and boosting overall energy efficiency. The system’s modular design facilitates straightforward scalability, allowing for future expansions like the integration of more renewable energy sources or increased storage capabilities. This strategy not only meets the present demands of residential users but also lays the groundwork for future smart grid solutions, promoting a more robust and flexible energy network.
Authors
- Zaid Hussein Ali (ORCID: https://orcid.org/0000-0003-1665-3295)
- David Raisz
Institutions
- Budapest University of Technology and Economics (HU)
- Northern Technical University (IQ)
Publication Details
- Journal
- Energy Conversion and Management X
- Published
- 2025-04-01
- DOI
- https://doi.org/10.1016/j.ecmx.2025.100997
- Citations
- 2
- Primary Topic
- Microgrid Control and Optimization
- Type
- article
- Field-Weighted Citation Impact
- 2.43
Funders
- Budapesti Műszaki és Gazdaságtudományi Egyetem