Assessment of Low Voltage Ride-Through behaviour of several wind farms with crowbar protection

Recently, as wind farms have increasingly been built on the same wind belt to make good use of wind resources, the interactions between wind farms and the grid have become more complicated. Requirements like Low Voltage Ride-Through (LVRT) capability and its impact on neighboring wind farms, therefore, pose higher challenges, particularly in case of several wind farms on the same wind. This paper focuses on the performance of several wind farms when in severe transmission disturbances. Equations are derived to estimate the stator and rotor peak current of wind generator and the IEEE 39 Bus System is applied to analyze the LVRT capability of several wind farms by using DIgSILENT/PowerFactory. The results indicate that the LVRT capability is affected by increased wind farms in the vicinity and different fault locations. The capability can be improved by applying proper crowbar switching strategies as illustrated through simulations.