The invention relates to a photovoltaic MPPT (
Maximum Power Point Tracking) method based on an improved grey wolf optimization
algorithm. According to the technical scheme, the method comprises the steps: S1, selecting N random values from [0, 1] to serve as the initial position of a grey wolf
population, wherein grey wolf individuals represent the duty ratio in a
photovoltaic system; S2, acquiring the output power of the
photovoltaic system under the control of each duty ratio, taking the output power as the fitness of
gray wolf individuals, and recording the three gray wolves with the maximum fitness as alpha wolf, beta wolf and
delta wolf in sequence; S3, shrinking the search range of the grey wolf
population, and updating the upper and lower limits of a search interval; S4, performing position updating on the grey wolf
population by using an improved position updating formula; S5, executing reverse search, comparing with
gray wolf population fitness, and updating alpha wolf, beta wolf and
delta wolf; S6, judging whether a termination condition is met or not, and if yes, stopping iteration and stabilizing the
photovoltaic system at the duty ratio corresponding to the alpha wolf; otherwise, returning to the step S2, and continuing iteration.