Maximum power tracking capture photovoltaic control method with self-adaptive search algorithm

Abstract

The invention discloses a maximal power tracing and catching photovoltaic controlled method with self-adaptive searching algorithm, which comprises the following steps: setting initial step-length; monitoring the voltage and the current of the i time solar battery array; evaluating the i time power; getting voltage change quantity delta Ui and power change delta Pi of the i time and the i-1 time; judging whether the delta Ui is 0; backing to sample if delta Ui=0; evaluating slope delta Pi / delta Ui of P-V curve if delta Ui is not equal to 0; judging whether delta Pi / delta Ui absolute value is not less than the setting accuracy E; un-changing dutycycle of buck circuit switching tube if |delta Pi / delta Vi|=E. This invention does not need device to test light intensity and temperature, which can decrease the cost of solar electric power generation system.

Description

technical field [0001] The invention relates to a special control device in a solar photovoltaic power generation system, and belongs to the technical field of combining power electronics technology and control technology. Background technique [0002] With the development of social economy, the consumption of energy and resources is getting faster and faster. Saving energy and protecting the environment have become a necessary condition for the sustainable development of human beings. People's attention is shifting from conventional energy to the development and utilization of renewable energy. As a huge amount of renewable energy, solar power has become a very important part of global development. One of the swiftest techniques. A solar cell is a device that uses the photovoltaic effect to convert light energy into electrical energy. The basic structure is a large-area diode. The phenomenon that a substance absorbs light energy to generate an electromotive force is calle...

AI Technical Summary

Problems solved by technology

The perturbation observation method also has great shortcomings: the perturbation method makes the operating point only oscillate at the maximum power point of the array, resulting in partial power loss, and the given initial value and tracking step size have a large impact on the search range and speed. Influence; the perturbation method sometimes produces the vector sequence ("misjudgment") phenomenon of the program during operation, so that the operating point is far away from the maximum power point

The method of fixed ΔU search and tracking is simple in design and easy in calculation, but due to the nonlinearity of the output power of solar cells, the contradiction between tracking accuracy and tracking speed is difficult to solve better

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