Grid-connected and off-grid integrated solar power generation subsystem and system

Abstract

The invention provides a grid-connected and off-grid integrated solar power generation subsystem and system. The subsystem comprises a master control module which obtains the voltage and current information of a solar module, an energy storage module and a mains supply module, switches a power supply state according to the obtained voltage and current information and outputs a corresponding control command, a maximum power tracking module which boosts a direct current outputted by the solar module to obtain a boosted direct current for the power supply of a load, a bidirectional DC conversionmodule which performs charging or power supply of the energy storage module according to the corresponding control command, and an inverter module which receives the boosted direct current through a bus, carries out AC conversion on the boosted direct current according to the corresponding control command and outputs an alternating current supplied to the load, wherein the charging of the energy storage module is to step down the received boosted direct current and store the direct current into the energy storage module, the power supply of the energy storage module is to boost the voltage ofthe energy storage module and outputs the boosted direct current for the power supply of the load. The energy conversion is reduced, and the subsystem is convenient to use.

Description

technical field [0001] The invention relates to the field of power electronics, in particular to a grid-connected and off-grid integrated solar power generation sub-system and system. Background technique [0002] The off-grid solar power generation system refers to that the electricity generated by the photovoltaic power generation system is stored in the battery, and converted into AC power for direct use by the power-consuming equipment through the inverter, or directly supplies electricity for the DC power-consuming equipment without inverter. Connected to the grid. It is widely used in remote mountainous areas, areas without electricity, islands, communication base stations and other application places. The system generally consists of a photovoltaic array composed of solar cell components, a solar charge and discharge controller, a battery pack, an off-grid inverter, a DC load and an AC load, etc. The photovoltaic array converts solar energy into electrical energy wh...

AI Technical Summary

Problems solved by technology

When the inventor implemented the integrated solar power generation subsystem of the present invention, he found that this method has the following defects: in areas where the power supply is relatively stable, it is generally powered by the mains, and the energy generated by the solar modules It will be converted into battery voltage for energy storage, and then provided to the inverter circuit by the battery through the step-up link when the mains power is lost.

When the power supply is sufficient, the solar energy is converted into battery power, and multi-level energy conversion leads to a decrease in conversion efficiency and power loss

Due to the low voltage of the battery, the input voltage of the solar module array is limited, which leads to more parallel connection of solar modules during the construction process, making construction difficult

For this reason, the off-grid solar power generation system is not suitable for use in places where electricity is convenient, and it is difficult to be widely used.

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