In a collaborative effort with a researcher Akgül from Department of Mathematic, Near East University, a study introduces a novel approach to enhance the performance and stability of grid-connected solar photovoltaic (PV) systems amidst variable shading conditions. The paper proposes a hybrid modular multilevel converter (MMLC) design aimed at optimizing power generation and mitigating power quality issues without the need for additional active or passive filters.
Traditional MMLCs face challenges in achieving high power output due to increased complexity and losses stemming from the necessity of employing numerous cells for voltage level generation. In contrast, the hybrid MMLC proposed in this research minimizes losses and complexity by employing fewer IGBT switches while maintaining the same number of output levels. This innovation leverages series and parallel connections of half and full bridge cells within the converter configuration to boost power production and improve voltage output.
To address fluctuations in input irradiation and temperature that impact output parameters such as voltage, current, and power, the study introduces a zero sequence control (ZSC) strategy. By injecting zero sequence voltage (ZSV) into each phase of the converter output, the proposed approach ensures balanced power distribution among the phases feeding into the low voltage grid. Simulation results conducted using PSCAD software demonstrate the effectiveness of the hybrid MMLC in stabilizing power output and improving performance under varying environmental conditions.
Furthermore, the study underscores the versatility of the proposed converter model, which can accommodate additional PV panels to scale up power generation capacity. Additionally, while the zero sequence converter is primarily utilized for active power balancing in this research, its applicability can be extended to include reactive power compensation in future studies. The integration of battery storage systems represents a promising avenue for further enhancing the utility and effectiveness of the proposed approach in grid-connected PV systems.
In conclusion, this research offers a comprehensive solution to optimize power generation, stabilize output parameters, and enhance the overall performance of grid-connected solar PV systems. By addressing power quality issues and improving system efficiency, the proposed hybrid MMLC design holds significant promise for advancing the integration of renewable energy sources into the electrical grid, contributing to a more sustainable and resilient energy infrastructure.
More Information:
https://www.sciencedirect.com/science/article/pii/S2090447923001077
