A Grid-connected Microgrid System Based on Electric Power Exchange Sub-microgrid

Abstract

The invention belongs to the technical field of new energy microgrids, and specifically relates to a grid-connected microgrid system based on a power and electric energy switching sub-microgrid. According to the invention, a new energy microgrid connected with a public grid is designed into a grid-connected microgrid and the power and electric energy switching sub-microgrid, wherein the grid-connected microgrid and the power and electric energy switching sub-microgrid can operate independently, and are respectively connected with a controlled switch and the public grid. Moreover, the power and electric energy switching sub-microgrid is controlled and selected to be connected with the grid-connected microgrid or the public grid, thereby enabling the grid-connected microgrid and the public grid to operate independently. In addition, the power and electric energy switching sub-microgrid undertakes the seamless switching of the power and electric energy between the grid-connected microgrid and the public grid, thereby achieving the electric energy complementation between the microgrid and the public grid for operation, and achieving the local consumption of the new energy microgrid and a mode that the new energy power is mostly self-generated and self-consumed and the remaining power is used for surfing on the Internet. Furthermore, when the public grid is cut off, the grid can be automatically switched to the microgrid for off-grid operation, thereby guaranteeing the uninterrupted power generation and supply for a microgrid user, and effectively achieving the electric energy complementation of the grid-connected microgrid and the public grid and the reasonable switching of grid connection and grid disconnection.

Description

technical field [0001] The invention belongs to the technical field of new energy microgrids, and in particular relates to a grid-connected microgrid system based on electric power exchange sub-microgrids. Background technique [0002] In the application of new energy microgrid, the new energy microgrid connected to the public grid is one of the important ways of new energy application in areas with electricity, and it is also the main direction of new energy application in the future. It is generally believed that a typical microgrid is a distributed power supply, Energy storage devices and power loads are connected to the power bus of the microgrid through power electronic devices. Through the control of the switch at the PCC at the connection point of the public grid, the conversion of the grid-connected operation of the microgrid to the off-grid island mode is realized; its operation needs to be realized The microgrid and the public grid complement each other, that is, t...

AI Technical Summary

Problems solved by technology

[0003] At present, when two or more power grids are switched online in real time, the operation mode of first shutting off, then switching, and then closing is mainly adopted under the control of fast switches. Due to the timeliness of control, seamless switching cannot be achieved, especially for large Large-scale grid-connected microgrids are even worse

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