Research of kind of variable step size perturbation and observation MPPT based on power prediction

摘要

Based on the characteristics of the voltage and power of photovoltaic cells, an improved perturbation and observation method which achieves the maximum power point quickly is investigated in this paper. The method uses the power prediction method to estimate the disturbance direction in order to avoid the miscarriage of justice,gives a new step size algorithm and then through the variable step perturbation and observation method for maximum power point tracking.what is more,it has the advantages of fast tracking speed, high accuracy, and can avoid the possibility of error in the tracking process with the purpose of ensuring the system to track the maximum power point quickly and accurately. Compared with the traditional methods, simulation results show that this new method reaches the maximum power point in a shorter time with a more accurate maximum power and can overcome the contradiction between the speed and precision in MPPT.