Control method for tracking maximum power point of photovoltaic grid-connected generation

Abstract

The invention discloses a control method for tracking maximum power point of photovoltaic grid-connected generation, which comprises the steps of: taking the iteration initial values of duty cycle D, with Dm equal to 0.2 and Dn equal to 0.9; computing an iteration variable Dy of a maximum power point from an upper line and an iteration variable Dx of a maximum power point from a lower line; computing maximum power Py of Dy according to the iteration variable Dy of the maximum power point from the upper line and detected voltage Uy and Iy thereof; computing maximum power Px of Dx according to the iteration variable Dx of the maximum power point from the lower line and detected voltage Ux and Ix thereof; and computing the maximum duty cycle Dmax by using a golden section method. The controlmethod can realize the computation of the maximum power point and is particularly applicable to the effective tracking of the maximum power point when solar power photovoltaic equipment is started orrestarted.

Description

technical field [0001] The invention relates to the technical field of solar photovoltaic grid-connected power generation, in particular to a maximum power point tracking control method for solar photovoltaic grid-connected power generation. Background technique [0002] The solar photovoltaic power generation system absorbs sunlight through solar cells and converts the sun's light energy directly into electrical energy output. The mainstream development trend of photovoltaic power generation system (hereinafter referred to as photovoltaic system) is grid-connected photovoltaic power generation system. The power generated by solar cells is a DC voltage, which must be converted into AC by an inverter device, and then used together with the AC power of the grid. This form of photovoltaic system is a grid-connected photovoltaic system. Photovoltaic grid connection is the development trend of solar energy utilization. Photovoltaic power generation systems will be mainly used in...

AI Technical Summary

Problems solved by technology

This method can quickly track illumination changes and the array voltage swing is smaller than the perturbation and observation method; the disadvantage is that the algorithm is more complicated, and when it is implemented by a digital method, the judgment of the maximum power point is prone to errors

[0009] In fact, the maximum power point is completely unknown when the lighting conditions such as the battery array is blocked and the system is restarted artificially. Technical Problems of Power Point Tracking Effectively

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