Photovoltaic energy storage power generation module based on Lyapunov switch coupling extremum search

Abstract

The invention discloses a photovoltaic energy storage generating module based on Lyapunov switch coupling extremum searching. The photovoltaic energy storage generating module comprises a photovoltaic battery unit interface, a photovoltaic battery voltage equalization unit, an SEPIC feed buck-boost conversion unit, a lithium ion battery unit interface, a switching unit and a main control unit, wherein the SEPIC feed buck-boost conversion unit is connected with the photovoltaic battery voltage equalization unit in series; the switching unit is connected with the SEPIC feed buck-boost conversion unit and a lithium ion battery unit; and the main control unit is connected with the switching unit and a 2-Lyapunov extremum searching MPPT control sub unit. The 2-Lyapunov extremum searching MPPT control sub unit comprises a front-stage photovoltaic voltage equalization Lyapunov extremum searching MPPT control sub unit used for carrying out extremum searching on the photovoltaic battery voltage equalization unit, and a rear-stage SEPIC feed buck-boost Lyapunov extremum searching MPPT control sub unit used for carrying out extremum searching on the SEPIC feed buck-boost conversion unit. The front-stage photovoltaic voltage equalization Lyapunov extremum searching MPPT control sub unit and the rear-stage SEPIC feed buck-boost Lyapunov extremum searching MPPT control sub unit carry out extremum searching alternately.

Description

technical field [0001] The invention belongs to the field of photovoltaic lithium batteries, in particular to a photovoltaic energy storage power generation module based on Lyapunov switch coupling extremum search. Background technique [0002] As a new type of energy, solar energy has attracted increasing attention, and photovoltaic power generation, one of its main applications, has a broad market prospect. However, the main disadvantage of solar energy is that the energy is unstable. It is not available during the day and at night, and the sunny day is strong and the cloudy day is weak. Usually, it is necessary to equip an energy storage battery to stabilize the influence of solar energy instability. Therefore, a photovoltaic energy storage power generation system emerges as the times require, which includes a photovoltaic cell for converting solar energy into electric energy and an energy storage battery for storing the electric energy generated by the photovoltaic cell....

AI Technical Summary

Problems solved by technology

Since the photovoltaic cells of the existing photovoltaic lithium battery energy storage system are connected in series with anti-reverse protection diodes, and the photovoltaic cells are directly connected to charge the lithium-ion cells, the existence of the forward voltage drop causes the photovoltaic cells to The charging efficiency of the unit to the lithium-ion battery unit is low, which reduces the energy utilization rate of the photovoltaic battery unit and cannot fully utilize the power supply potential of the photovoltaic battery unit

At the same time, although there is a balanced management of the photovoltaic lithium battery energy storage system, it has not effectively improved the shadow effect of photovoltaic cells, thereby reducing the energy utilization rate of photovoltaic cells.

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