MPPT control system and method for small-power wearable photovoltaic system

Abstract

The invention discloses an MPPT control system and method for a small-power wearable photovoltaic system.The MPPT control system comprises a solar cell, a filter capacitor C1, a DC-DC conversion unit, an open-circuit voltage sampling unit, a working voltage sampling unit, an MCU processor, a filter capacitor C3 and an energy storing unit.Sampling measuring is conducted to acquire the open-circuit voltage Uoc and the output voltage Vpv of the solar cell; controlling is conducted based on the approximate proportion relation of about 0.8 Uoc of the voltage Um at the maximum power point, the duty ratio of the DC-DC conversion unit is adjusted, and the output voltage Vpv of the solar cell is changed so that the solar call can work near the maximum power point; the working voltage Vpv1 and the working voltage Vpv2 of the solar cell are compared; if the difference of the Vpv1 and the Vpv2 is larger than voltage Q, an open-circuit voltage sampling switch Q2 is opened, and sampling measuring is conducted to acquire the open-circuit voltage Uoc; the duty ratio of the DC-DC conversion unit is adjusted, and the output voltage of the solar cell is changed.Maximization of energy collection can be achieved.

Description

technical field [0001] The invention belongs to the technical field of maximum power point tracking control of solar cells in a photovoltaic system, and in particular relates to an MPPT control system and method for a low-power wearable photovoltaic system. Background technique [0002] With the development of electronic information technology, there have been many mobile electronic devices carried by the human body, such as mobile communication tools, personal digital assistants, and medical electronic devices. Currently, most of these mobile electronic devices are powered by batteries. However, due to factors such as battery energy storage capacity, size, and service life, the battery power storage capacity in mobile devices is limited. When the battery power is exhausted, the device cannot be used, resulting in a limited use time of the device. With the research and development of new energy technologies, extracting energy from the surrounding environment and converting ...

AI Technical Summary

Problems solved by technology

However, the traditional open-circuit voltage method needs to interrupt the normal operation of the system to measure the open-circuit voltage in order to obtain the open-circuit voltage during the tracking process, which will inevitably cause temporary power loss.

In addition, conventional fuzzy control, neural network control, etc. have high requirements on hardware, and the control system is relatively complicated, and there are still certain limitations.

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