Scientists in Pakistan have developed a fuzzy reconfiguration method that can reportedly mitigate power losses due to shading and hotspot faults by up to 23.5% compared to conventional techniques. The proposed scheme is said to be suitable for both square and rectangular PV arrays of different sizes.
Scientists at Pakistan’s National University of Sciences and Technology have developed a new fuzzy logic technique to reduce power losses in PV systems due to partial shading and hotspot faults with different severity levels.
The proposed fuzzy reconfiguration scheme is reportedly suitable for both square and rectangular PV arrays of different sizes. “Six different scenarios of shading and hotspot faults are established in both arrays in order to cater maximum possible shading patterns,” the researchers explained, noting that the new technique proposes a generalized reconfiguration scheme for each scenario. “Different shading scenarios exhibit severity levels, which helps in the quantification of faults.”
The six scenarios consider partial shading with a uniform pattern, partial shading with a non-uniform pattern, and the insurgence of hotspots.
The research group also defined six power loss categories: Very small fault (VSF); small fault (SF); medium fault (MF): large fault (LF); very large fault (VLF); and hotspot fault (HF). It also established a dataset against each faulty scenario.
Image: National University of Sciences and Technology, Results in Engineering, CC BY 4.0
The novel technique was implemented experimentally in a 12-module (4 x 3) PV array, with each module having and output of 150 W.
“Fuzzy logic controller is implemented using Arduino uno microcontroller,” the scientists explained. “Initially, all panels are connected in series and parallel through switches. Opening and closing of switches reconfigure the PV system. A tilt of 30° and pitch of one foot is used.”
The experiments showed that the fuzzy reconfiguration method can mitigate power losses due to shading and hotspot faults by up to 23.5% compared to conventional techniques, the scientists said. “None of the reconfiguration techniques addresses mitigation of output power loss due to shadowing and hotspot faults with different severity levels in series/parallel (SP) configuration,” they added.
The proposed technique was introduced in “A fuzzy reconfiguration approach for mitigating power losses in PV systems,” published in Results in Engineering. “Overall, this research work provides insights into designing and developing fuzzy logic-based switching matrices for the PV industry to mitigate power losses due to shading and hotspot faults,” the academics concluded.
