Abstract
In actual operation, photovoltaic arrays inevitably encounter shadow problems, resulting in a power output decline and multiple peaks in the output characteristics. The effect of partial shade can be satisfactorily reduced by photovoltaic array reconfiguration. Almost all current reconfiguration techniques are based on the irradiance equalization principle. However, by analyzing the output characteristics of photovoltaic array, it is found that the irradiance equalization principle improves the output power by increasing only the minimum row current without considering the effect of the voltage, so the reconfiguration techniques based on this principle cannot obtain the global optimal configuration under some partial shading conditions. In order to maximize the output power of photovoltaic array under any partial shaded condition, this paper proposes a reconfiguration strategy based on direct power evaluation. In this approach, the reconfiguration problem is formulated as a 0-1 multi-knapsack problem, and a novel mathematical model is established to directly evaluate the maximum output power of photovoltaic array. Then, the optimal reconfiguration scheme is determined by solving the mathematical model. Finally, the effectiveness of the proposed reconfiguration strategy is proved in theory and simulations.
Highlights
Photovoltaic (PV) modules are connected in series and parallel to form a PV array [1]
Based on the analysis of the output characteristics of the PV array under partial shading conditions, this paper reveals the problems of the existing reconfiguration strategy based on the irradiance equalization principle
Since all the published methods are based on the irradiance equalization (IE) principle and their mathematical models are similar, the most ideal IE scheme can be obtained by any one of these methods under the premise of ignoring the differences in the computational abilities of the algorithms
Summary
Photovoltaic (PV) modules are connected in series and parallel to form a PV array [1]. The difference in electrical characteristics between PV modules will greatly reduce the output power of the entire PV array and cause local hot spots [2]. Bypass diodes are usually connected across each PV module to protect it from damage; this introduces multiple peaks in the P-V characteristics of a PV array [3]–[5]. The power loss caused by partial shading is related to the shading conditions and to the interconnection mode of a PV array [6]; among these modes, series-parallel (SP), total-cross-tied (TCT), and bridge-linked (BL) are the most common [7].
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.