| Abstract: | To coordinate the protection of PMSG (permanent magnet synchronous generator), collector circuits and outgoing
lines, a comprehensive and improved protection method of PMSG based wind farms with LVRT (low voltage ride
through) capability is proposed. The proposed method includes adding a short time delay to the collector network
current protection zone I and a directional protective relaying to the collector network protection, installing
grounding transformers and zero sequence current protection, and generator low-voltage protection action
improvement. A LVRT scheme consisting of variable resistance dumping circuit, grid side dynamic reactive power
control and reactive power compensation control is proposed. The fault characteristics of PMSG based wind farms
are analyzed, and a PMSG based wind farm in Dabancheng, Xinjiang, is used as an example to analyze typical wind
farm protection configuration, the setting values considering LVRT requirements, and the coordination problems.
Finally, an improved wind farm protection coordination methodology is proposed and its validity is verified by
simulation. |
