Enhancing Solar Photovoltaic Power Utilization Through String Inverter Technology: A Review
Keywords:
Grid-connected system, Maximum power point tracking, Solar photovoltaic, Solar power utilization, String inverterAbstract
Solar Photovoltaic (PV) systems are widely used for clean electricity generation, but their actual energy output is affected by changing solar irradiation, temperature, partial shading, module mismatch, and conversion losses. This paper studies the use of solar string inverter technology to improve the utilization of available photovoltaic power. In a string inverter arrangement, PV modules are connected in series to form separate strings, allowing the power produced by each string or group of strings to be managed more effectively. An important feature of this system is Maximum Power Point Tracking (MPPT), which continuously adjusts the operating condition of the PV array to extract higher available power when sunlight conditions change. The reviewed studies indicate that string-based conversion can reduce the interaction between differently performing PV strings and provide a modular approach to solar power conversion. The use of controlled DC conversion and multilevel inverter topology can also improve voltage regulation and AC output quality. One reviewed multilevel system achieved unity power factor with a reported total harmonic distortion of approximately 0.63%. Overall, string inverter technology provides an effective approach for improving solar-energy harvesting, system flexibility, power quality, monitoring, and reliable grid-connected operation.
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