Grid-connected and off-grid hybrid solar energy photovoltaic generating system

Abstract

The invention relates to a solar energy photovoltaic power generation application, particularly a hybrid photovoltaic generating system which mainly adopts grid-connected power generation but also can carry out off-grid power generation. The generating system comprises a controller, a solar cell array, a storage battery, a direct current emergency load, a grid-connected inverter and a public distribution network. Most direct current electric energy output by the solar cell array is converted into alternating current electric energy through a grid-connected inverter and then sent to the public distribution network; and small part of direct current electric energy is supplied to the direct current emergency load and the storage battery through a direct current buck converter and a low-voltage direct current bus. When the voltage of the low-voltage direct current bus is beyond the normal range, the storage battery can supply energy to the direct current emergency load through a charge-discharge controller. The grid-connected and off-grid hybrid solar energy photovoltaic generating system mainly adopts grid-connected power generation but also can carry out off-grid power generation; even when the public distribution network fails and grid-connected power generation is not available, the system also can supply energy to the direct current emergency load, thus improving the system efficiency and the annual generating time, and having a good application prospect.

Description

technical field [0001] The invention relates to an application of solar photovoltaic power generation, in particular to a hybrid photovoltaic power generation system capable of mainly generating electricity connected to the grid and simultaneously generating electricity off the grid. Background technique [0002] Solar photovoltaic power generation can replace and reduce the use of limited and non-renewable coal, oil, natural gas and other primary fossil energy and the secondary energy converted from it. Promoting the application of solar photovoltaic power generation is of great significance to reducing the consumption of fossil energy and optimizing the energy structure. [0003] Solar photovoltaic power generation does not emit pollutants that damage the atmosphere and the ecological environment, and is a clean and green energy that is in harmony with the ecological environment on which human beings depend. Promoting the application of solar photovoltaic power generation...

AI Technical Summary

Problems solved by technology

[0007]However, for the grid-connected power generation system, when the distribution network fails, in order to prevent the island effect, the grid-connected inverter will not be allowed to work, and the solar cells will The convertible electric energy of the array is not used; and for the off-grid power generation system, when the battery pack is fully charged and there is no electrical load, the solar cell array will not be able to generate electricity because there is no output load. The convertible power of the array is not utilized

Images