A parallel control method for large-capacity energy storage converters used in energy storage power stations

Abstract

The invention provides a parallel control method for high-capacity energy accumulation converters of an energy accumulation power station. The parallel control method comprises the steps that first, all electrical equipment in the energy accumulation power station is initialized; second, communication information is sent between PCS units; third, if the quantity of the communication information sent by the PCS units and the quantity of response information received by the PCS units are the same, the PCS units start to conduct grid connection; fourth, one PCS unit is determined to be used as a main machine, and the rest PCS units are slave machines; fifth, the slave machines conduct adjusting according to the output voltage of the main machine, and grid connection begins; sixth, if the slave machines do not complete grid connection within preset time, grid connection is stopped, and grid connection failure signals are sent. Compared with the prior art, according to the parallel control method for the high-capacity energy accumulation converters of the energy accumulation power station, on-line reliable parallel connection of the multiple energy accumulation converters can be achieved, and the capacity of the energy accumulation power station is expanded. The strategy of electrically free main machine seizing of the energy accumulation converters is adopted, the risk of faults caused by manually setting the main machine is avoided, and the reliability of the energy accumulation power station is improved.

Description

technical field [0001] The invention relates to a control method for an energy storage converter, in particular to a parallel control method for a large-capacity energy storage converter used in an energy storage power station. Background technique [0002] Energy storage power stations include pumped water storage power stations, wind energy pumped water storage power stations, and energy storage power stations that use large-capacity battery packs combined with various new energy sources for power generation. [0003] ①: The pumped storage power station is equipped with pumping-generating dual-purpose units, which can pump water and generate electricity. During the day and the first half of the night, the reservoir releases water, and the high water level water passes through the dual-purpose unit. At this time, the dual-purpose unit acts as a generator to convert the mechanical energy of the high water level water into electrical energy and transmit it to the grid. Solve...

AI Technical Summary

Problems solved by technology

[0005] For energy storage power stations using energy storage batteries as energy storage devices, the capacity of the energy storage battery cells is small, and the battery system needs to be composed of battery cells connected in series and parallel, and then connected to a single energy storage converter (Power conversion system , PCS), due to the limited capacity of the battery system and PCS system, it is currently unable to meet the power requirements of megawatt power plants. Parallel connection will lead to voltage and current sharing problems between systems. If it is not handled properly, it will cause the life of the energy storage battery to be reduced or damaged, and it will cause circulation between PCS systems and cause equipment failure.

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