LVRT and HVRT control strategies of doubly- fed induction generator

The Doubly Fed Induction Generator (DFIG) has a high sensitivity to the Grid Faults (GFs), which can cause many problems on the power quality and the production continuity. Actually, the grid connection requirements impose strict laws to respect to Low Voltage Ride Through (LVRT), High Voltage Ride Through (HVRT), and grid support capacities following the Grid Codes (GCs). In fact, when detecting voltage fault, Wind Turbines (WTs) should stay in connection with the grid in order to hold a safe and stable operation. The main objective of this work is to propose LVRT and HVRT strategies able to retain WTs connected to the grid during severe grid voltage faults. The proposed approach is a hybrid method combining two methods (active and passive methods): The first aim is to develop the control of DFIG, while the second is applied for severe voltage faults using hardware protection circuits