Dynamic FRT belt for wind turbines

Abstract

The invention relates to a method for controlling at least two converter-based power supplies, comprising the following steps: presetting a first droop for a first converter-based power supply; presetting a second droop for a second feed based on the converter, wherein the second droop is different from the first droop; the converter-based first feed is controlled according to the first droop and the converter-based second feed is controlled according to the second droop. The invention also relates to a wind turbine and to a wind farm.

Description

technical field [0001] The invention relates to a method for controlling at least two converter-based feeders. Background technique [0002] Converter-based feeders, such as wind energy installations, wind farms or photovoltaic installations, usually have the so-called FRT characteristic (Fault Ride Through). [0003] This means, in particular, that the converter-based feeder supports the grid voltage of the supply network with the aid of additional reactive current or additional reactive power during a grid fault in the supply grid [0004] Thus, with the aid of the FRT characteristic, converter-based feeders support the grid voltage of the supply grid, ie shift the grid voltage of the supply grid to Within normal range, for example from 0.95p.u. to 1.05p.u. of grid rated voltage. [0005] In the case of the usual load connection within the supply network, it can now happen that the grid voltage of the supply network briefly leaves the permissible range of the grid voltag...

AI Technical Summary

Problems solved by technology

[0007] If there are now too many converter-based feeders with such an FRT characteristic in the corresponding network segment of the supply network, triggering the FRT characteristic simultaneously and over a large space may lead to The feeder supports the grid voltage, but the supply grid is stuck at an operating point that is outside the permissible range of the grid voltage

[0008] In this case, for example, there is a permanent undervoltage at the converter-based feeder, which leads to separation of the converter-based feeder from the corresponding network segment, i.e. the supply network

[0009] The FRT characteristics of converter-based feeders can cause grid support to occur, but converter-based feeders can still accidentally become disconnected from the supply grid, which in turn can lead to grid instability and, in the worst case, lead to power grid outage

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