V. CONCLUSION
In this paper, an improved P&O algorithm using FLC has
been proposed by referring to the mechanisms of the
conventional P&O algorithm and nonlinear characteristics of
photovoltaics. The strategy to create adaptive perturbation
offsets for accelerating the MPPT velocity and improving the
MPPT efficiency were validated by the simulation and
experimental results. As mentioned in this paper, the tracking
range and perturbation offset determine the overall
performance of the MPPT control strategies. In practice,
although the P-V characteristics of PVs could frequently vary
due to the temperature, shading, and irradiation conditions,
especially in a cloudy day, a self-checking mechanism that is
embedded into the proposed fuzzy rule base can be easily
activated under the changes of temperature, shading, and
irradiation conditions.