Maximum power point tracking system and method for photovoltaic power generation system

Abstract

The invention discloses a maximum power point tracking system and a method for a photovoltaic power generation system. The system comprises an internal resistance sensor, wherein the internal resistance sensor provides alternating current signals into a direct current main loop of the photovoltaic power generation system and can simultaneously obtain and compare the alternating current response signals with the same frequency as the alternating current on the equivalent output impedance of a solar panel and the equivalent input impedance of a maximum power point tracking (MPPT) controller, a comparison result is obtained, and the output pulse duty ratio of the MPPT controller is regulated until the comparison result is zero. Through the full circuit ohm law, when the impedance value of the equivalent load is the same as the internal resistance of a power supply, the power supply output power obtained by an equivalent load is maximum, and the maximum power point is reached. The method can be used for detecting the maximum power point of the system in real time, in addition, the change of the maximum power point is accurately and fast tracked, so the power consumption caused by oscillation regulation of the output voltage value and the current value of the solar panel and the searching of the changed maximum power point is eliminated, and the output efficiency of the photovoltaic power generation system is improved.

Description

technical field [0001] The present application relates to the technical field of photovoltaic power generation, in particular to a maximum power point tracking system and method for a photovoltaic power generation system. Background technique [0002] The solar panel is affected by light, temperature, etc., and the output power also changes all the time. The maximum power point tracking means that the MPPT (Maximum Power Point Tracking, maximum power tracking) controller can detect the output voltage value and current value of the solar panel in real time. , and adjust the output power of the photovoltaic power generation system, that is, change the load impedance and then change the voltage and current values ​​of the system, so that the actual output power of the system is as close as possible to the current theoretical maximum output power, so as to supply power to the load with the highest efficiency. [0003] The maximum power tracking system in the prior art at least i...

AI Technical Summary

Problems solved by technology

[0006] In order to solve the above technical problems, the embodiment of the present application provides a maximum power point tracking method and device for a photovoltaic power generation system to solve the problem of low output power utilization of the photovoltaic power generation system. The technical solution is as follows:

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