Adaptive step-size photovoltaic maximum power tracking method and system based on conductance increment

Abstract

The invention relates to a self-adaption step-length photovoltaic maximum-power tracking method based on an electrical conductance increment. The method comprises the steps that S1, an output currentand an output voltage of a photovoltaic battery are collected, and an output power, an output power increment and a voltage increment of the photovoltaic battery at the current time period and the last time period are acquired; S2, a relation between an absolute value of a specific value of the output power increment to the voltage increment and a set vibration threshold value is judged, and the step length is selected; S3, the plus or minus of a product of the output power increment and the voltage increment is judged, and the step length is determined; S4, the acquired step length is added to a reference duty ratio, and a control signal for controlling switch-on and switch-off of a Boost circuit is generated. The invention further discloses a system of the self-adaption step-length photovoltaic maximum-power tracking method based on the electrical conductance increment. The system comprises the photovoltaic battery, an MPPT controller, a current and voltage collection module, a vibration threshold value setting module, a step length setting module and a PWM control module. Compared with the prior art, the method has the advantages of self-adaption step-length selection, quick andstable tracking and the like.

Description

technical field [0001] The invention relates to the technical field of photovoltaic power generation, in particular to a method and system for tracking photovoltaic maximum power with an adaptive step size based on conductance increment. Background technique [0002] Solar photovoltaic power generation is considered to be the most promising new energy technology in the world at present. All developed countries have invested huge sums of money to compete in research and development, actively promote the process of industrialization, and vigorously develop market applications. However, the photovoltaic power generation industry has also encountered many problems in the development: (1) high cost of photovoltaic cells; (2) low photoelectric conversion efficiency; (3) the harm of partial shading. Maximum power point tracking is the most direct and effective method to reduce power generation costs and improve power generation efficiency. Most of the existing maximum power point t...

AI Technical Summary

Problems solved by technology

However, the photovoltaic power generation industry has also encountered many problems in the development: (1) high cost of photovoltaic cells; (2) low photoelectric conversion efficiency; (3) the harm of partial shading

However, intelligent algorithms often have the disadvantages of many control parameters, complex control ideas, and high hardware requirements, which restrict the engineering practice application of these algorithms to a certain extent, and as the operating environment of photovoltaic cells becomes more and more complex, Due to the shading of buildings, trees or dust, it often happens that the surface of the photovoltaic cell receives uneven light intensity. At this time, the photovoltaic power-voltage characteristic curve will have multiple peaks.

Some intelligent algorithms, like the traditional maximum power point tracking method, lack the ability of global optimization, and are only suitable for single-peak maximum power tracking systems. When tracking multi-peak systems, it will cause tracking failure

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