Abstract: |
Large integration of doubly-fed induction generator (DFIG) based wind turbines (WTs) into power networks can
have significant consequences for power system operation and the quality of the energy supplied due to their
excessive sensitivity towards grid disturbances. Under voltage dips, the resulting overcurrent and overvoltage in the
rotor circuit and the DC link of a DFIG, could lead to the activation of the protection system and WT disconnection.
This potentially results in sudden loss of several tens/hundreds of MWs of energy, and consequently intensifying
the severity of the fault. This paper aims to combine the use of a crowbar protection circuit and a robust
backstepping control strategy that takes into consideration of the dynamics of the magnetic flux, to improve DFIG’s
Low-Voltage Ride Through capability and fulfill the latest grid code requirements. While the power electronic
interfaces are protected, the WTs also provide large reactive power during the fault to assist system voltage
recovery. Simulation results using Matlab/Simulink demonstrate the effectiveness of the proposed strategy in terms
of dynamic response and robustness against parametric variations. |
Key words: Wind turbine, DFIG, Grid faults, Crowbar protection, Backstepping control, Low-voltage ride through |
DOI:10.1186/s41601-020-00172-w |
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Fund: |
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