Grid-connected and off-grid power supply system and method

Abstract

The invention discloses a grid-connected Internet disconnection power supply system and a method thereof. The grid-connected Internet disconnection power supply system comprises a power supply bus, a power grid, a generating set, a power detection module, a measuring and calculating module, a preset module, a comparison module, a calculating module, a determination module and a control module. The generating set and the power grid simultaneously provide power for a load. During usage, the preset module sets power-grid expected output power. When the power detection module detects that actual output power of the power grid is greater than the power-grid expected output power, the determination module determines a size relationship of a generating-set installed capacity and set expected output power. If the generating set can satisfy the set expected output power, the control module makes the power grid output as the power-grid expected output power and the generating set output as the set expected output power, and passive control is changed into active control. An electricity demand to the power grid is effectively reduced, and simultaneously normal power supply of the power grid is avoided from being impacted and energy supply reliability and equipment security are guaranteed.

Description

technical field [0001] The invention relates to the technical field of power supply systems, in particular to a power supply system and method for grid-connected and off-grid. Background technique [0002] The building-type power supply system using generator sets has two schemes: isolated grid operation and grid-connected operation. During grid-connected operation, it is divided into grid-connected and grid-connected and off-grid according to the requirements of the grid. A reasonable generator set power supply scheme is an energy project. The key to success or failure. At present, the grid-connected and off-grid power supply scheme is usually realized by "reverse power" protection. A power direction detection device is installed at the grid power supply. When the grid absorbs energy is detected, a signal is sent to cut off the output switch of the generator set or the grid switch. However, such a design will cause a sudden change in the output power of the generator set, ...

AI Technical Summary

Problems solved by technology

However, such a design will cause a sudden change in the output power of the generator set, causing shutdowns, short-term energy absorption by the grid, causing problems such as grid protection and metering abnormalities, which seriously affect the reliability of energy supply and equipment safety.

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