Dynamic Efficiency of Direct Control Based Maximum Power Point Trackers

Due to stringent standards for efficiency of maximum power point tracker (MPPT) of photovoltaic (PV) system, the performance of MPPT in PV system under dynamic environmental conditions is very crucial. Thus, this paper evaluates the performance of perturb & observe (P&O) and incremental conductance (IC) MPPT techniques using the European Efficiency Test, EN 50530, which is specifically devised for the dynamic performance of PV system. Both MPPT techniques are implemented in direct control structure in conjunction with a buck-boost converter, which is used for tracking device. Experiments are conducted using a custom designed PV array simulator. Results reveal that both methods yield almost equivalent MPPT efficiency, however, in average, the performance of IC method is found to be slightly better that gives 98.5% efficiency compare to 98.3% in P&O. It is also seen that the performance of IC method is very sensitive to its perturbation size, especially at low insolation levels.