Island detection method for photovoltaic power plant based on SVG regulating power factors

Abstract

The invention discloses an island detection method for a photovoltaic power plant based on SVG regulating power factors. The island detection method comprises the following steps: (1) executing the step (2) when the active power outputted by the photovoltaic power plant is equal to or higher than a threshold value, and executing the step (3) when the active power outputted by the photovoltaic power plant is lower than the threshold value; (2) the SVG outputting reactive power according to the requirements of the voltage amplitude or power factor as the photovoltaic power plant is under grid-connected operation, and carrying out the island detection and performing the step (4)if the photovoltaic power station is under islanded operation; (3) the power factor output to the PCC by the photovoltaic power plant system being reduced by 0.05 to 0.1 than the predetermined value, and the power factor output to the PCC by the photovoltaic power plant system being a determined value if the frequency change at the PCC exceeds the threshold, the photovoltaic power station is under islanded operation and the active power outputted by the photovoltaic plant exceeds or equals to the threshold; (4) collecting the three-phase voltage signal at PCC, calculating the voltage amplitude and frequency; and determining the operating status of the system according to the voltage amplitude and the frequency value.

Description

technical field [0001] The invention relates to the technical field of power system analysis, in particular to an islanding detection method of a photovoltaic power station based on SVG to adjust power factor. Background technique [0002] In order to solve the increasingly severe energy crisis and environmental problems, the grid-connected photovoltaic power generation technology has developed rapidly. The cumulative installed capacity of photovoltaic power generation in China has reached about 47GW, becoming the country with the largest cumulative installed photovoltaic capacity in the world, of which about 90% are concentrated photovoltaics power station. Not all the transmission systems of photovoltaic power plants use dedicated channels. After the upstream protection of the system is activated, when the photovoltaic power plant is operating in an isolated island, the reclosing, backup and automatic switching and other equipment cannot operate normally, which seriously a...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide an islanding detection method for photovoltaic power plants based on SVG to adjust the power factor, which can effectively solve the problems of weak disturbance signals or mutual cancellation or amplification of disturbance signals in traditional active methods, and can quickly and reliably detect system running in silos

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