Parameter Extraction Testbed to Optimize Interconnections of Non-Planar Photovoltaics

The performance of photovoltaic (PV) systems drops considerably due to partial shading. Partial shading is inherent to non-planar PV applications where the surface normal of various segments of the PV material is not uniformly oriented, which causes non-uniform insolation. A mitigation technique is to optimize the interconnections between the PV elements to yield the highest energy harvest by finding and grouping the homogeneous cells. This paper presents results from an experimental study using a new experimental testbed that was developed to extract PV parameters in-situ. The experimental testbed is flexible, scalable, and suitable for research and development of non-planar PV applications. The benefit of this testbed is to collect data considering factors like cell aging, partial shading, and temperature effects. Such factors are not accounted for in manufacturer datasheets. The non-planar experimental setup enables the testing of a variety of PV interconnections to gather the characteristic i-v and p-v curves for PV characterization. Extracted parameters can then be used to model, simulate, and emulate the operation of the non-planar PV systems. Developed simulation and emulation models are used for testing and tuning maximum power point tracking (MPPT).