MPPT control method based on resistance matching of photovoltaic power generation system

Abstract

The invention discloses an MPPT control method based on resistance matching of a photovoltaic power generation system. A fuzzy MPPT controller samples voltage and current values of a photovoltaic array in the power generation process in real time by means of a voltage and current circuit, an MPPT fuzzy control algorithm of the fuzzy MPPT controller is used to generated a PWM control signal by calculation and processing, the PWM control signal is used to control work of a Boost circuit, the duty ratio of a DC chopper circuit is adjusted, the load impedance matching is controlled, and thus, theinternal resistance of a circuit of the photovoltaic power generation system matches the load impedance most rapidly. The method has the advantages that the circuit of the photovoltaic power generation system can be started for power generation at extremely low illumination intensity, relatively low circuit serial resistance and very low consumption of the circuit itself by means of photovoltaic array simulation and fuzzy control, the photovoltaic power generation system can get up early and sleep late, the power generation time of the system is prolonged, the MPPT fuzzy control algorithm enable the system to run at the maximal power point, and the power generation capacity of the photovoltaic power generation system is improved.

Description

Technical field [0001] The invention relates to the field of photovoltaic power generation, in particular to an MPPT control method based on resistance matching of a photovoltaic power generation system. Background technique [0002] The power output of the photovoltaic array has a nonlinear relationship with voltage and current, but under certain conditions of light intensity and temperature, the output of the photovoltaic array has a maximum power point, which requires dynamic control to track the maximum power point under different conditions ( Maximum powerpoint tracking abbreviation: MPPT). [0003] MPPT control is essentially an optimization process. By measuring voltage, current and power, comparing their changes, determine the positional relationship between the current operating point and the peak point, and then control the current (or voltage) to the current operating point and The peak power point moves, and finally the control current (or voltage) swings back and fort...

AI Technical Summary

Problems solved by technology

The traditional control is a PID (proportion, integral, derivative) control algorithm based on the conductance increment principle or the disturbance observation principle. PID control has low tracking accuracy, slow speed, and is sensitive to external disturbances and parameters. Disadvantages such as poor perturbation robustness, energy can not be used efficiently

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