Method and system for coordinately controlling reactive voltage of photovoltaic power station

Abstract

The invention provides a method and a system for coordinately controlling a reactive voltage of a photovoltaic power station. The method and the system measure the voltage of a grid-connected point ofa photovoltaic power station and the voltage of an in-station inverter, and the measured value is compared with a preset first threshold value interval of normal work; when the grid-connected point of the photovoltaic power station suddenly rises / falls in a voltage transient state in a normal working interval, voltage optimal value adjustment is carried out to coordinate reactive power distribution between the SVG and the in-station inverter, and when the grid-connected point voltage and the generator terminal voltage of the photovoltaic power station exceed a first threshold interval, the SVG and the in-station inverter enter an emergency closed-loop control mode to carry out reactive power adjustment respectively. According to the method and the system, the reactive power distributionbetween the SVG and the in-station inverter is coordinated when the voltage of the grid-connected point of the photovoltaic power station is suddenly increased / decreased, so that the transient reactive power support capability of the photovoltaic power station when the voltage of the grid-connected point of the photovoltaic power station is suddenly increased / decreased is better improved.

Description

technical field [0001] The present invention relates to the field of electric power control, and more specifically, relates to a method and system for coordinated control of reactive voltage of a photovoltaic power station. Background technique [0002] As one of the most mature and promising renewable energy sources, photovoltaic power generation has maintained a strong momentum of development in recent years. In the near future, the proportion of new energy in some local power grids may reach 80% or even higher. Grid-connected operation of new energy sources will become an important feature of the future power structure. [0003] However, as the proportion of new energy in the power grid is getting higher and higher, its influence on the power grid is also gradually expanding from the local area. The output of new energy units has obvious intermittency and volatility, which makes the large-scale integration of photovoltaic power generation put great pressure on the stable...

AI Technical Summary

Problems solved by technology

SVG consumes a large amount of factory power during work, which affects the economy, and in areas where a large number of new energy sources are connected to the grid, the simultaneous use of SVG actions at multiple grid-connected points will also bring about the coordination of dynamic voltage support.

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