Hybrid wind power plant group coordination control method under power grid asymmetrical faults

Abstract

The invention discloses a hybrid wind power plant group coordination control method under power grid asymmetrical faults, and relates to control of a grid-side converter and a machine-side converter of a permanent magnet direct drive wind power system; the hybrid wind power plant group comprises a permanent magnet direct drive wind power plant and an asynchronous wind power plant; in the premise of not increasing hardware equipment, the active power output of the permanent magnet direct drive wind power plant is limited while the current margin of the grid-side converter is fully utilized; on the basis of controlling the output of the grid-side converter to satisfy positive sequence reactive power of the power grid guiding rule, the residual current margin is utilized to output a negative sequence current to realize synergistic inhibition of the grid-connected point negative sequence voltage, reduce adverse influence of the operation behaviors of the permanent magnet direct drive wind power plant to the operation behaviors of the asynchronous wind power plant, and effectively improve the power-grid fault operation capability and the grid-connected electric energy quality of the asynchronous wind power plant.

Description

technical field [0001] The invention relates to the technical improvement of a hybrid wind farm group containing a permanent magnet direct drive wind farm and an asynchronous wind farm, in particular to a method for the hybrid wind farm to effectively suppress the negative-sequence voltage of a grid-connected point under an asymmetrical fault of the power grid, and belongs to the technical field of electric power control . Background technique [0002] Because different types of wind turbines have their own characteristics, in the expansion and reconstruction of old wind farms and the construction of new wind farms, it is an important trend for large-scale wind power utilization to use different types of wind turbines to form a hybrid wind farm and use different types of wind turbines to coordinate with each other. one. Since most of my country's wind power resources are concentrated in remote areas, the connection to the main power grid is weak, and asymmetric faults in th...

AI Technical Summary

Problems solved by technology

However, under the grid asymmetrical fault condition, there will still be negative sequence components in the grid voltage and current, which will interact with the positive sequence voltage and current components to cause serious fluctuations in the output power of the hybrid wind farm

When an asymmetrical fault occurs, if the permanent magnet direct drive wind turbine only injects positive sequence reactive power into the grid, it may aggravate the double-frequency fluctuation of the power of the entire hybrid wind farm, causing a serious decline in the output power quality of the entire hybrid wind farm

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