A part-stochastic (PSO) part-deterministic (HC, hill climbing) algorithm is employed to facilitate MPPT under partial shading conditions. The relevant paper is available at http://www.ped.pwr.edu.pl/pdf-80969-16967?filename=Hybrid%20MPPT%20algorithm%20for.pdf. The accompanying model has been developed by my colleague Karol Basinski. The search algorithm is similar to https://www.mathworks.com/matlabcentral/fileexchange/64056-hybrid-swarm-based-repetitive-controller-with-adaptive-forgetting-for-a-grid-tie-converter. If you are interested in PV modeling, there is also https://www.mathworks.com/matlabcentral/fileexchange/48319-photovoltaic-module-explicit-neural-model to help you start the adventure.