q*i*rd , are the reference values of the rotor currents in d- and q-axis. Stator active and reactive power ir can be controlled by regulating the d, q-axis components of rotor current. POWER GRID SYSTEM In the past wind turbines were separated from the grid following grid faults. However, as of now, separation of wind turbines for voltage values 80% of the nominal voltage would lead to loss of an undesirable portion of power generation. Therefore, utilities now require an FRT capability as specified in Fig. 8. Wind turbine must stay connected even when the voltage at the point of common connection (PCC) with the grid drops to zero. The 150-ms delay shown in the figure accounts for the normal operating time of protection relays. The red solid line in Fig. 1 marks the lower voltage boundary rather than any characteristic voltage behavior. (11) Fig. 8. through requirements. Fig.8. Schematic diagram of a grid connected DFIG wind turbine system.
q*i*rd , ir are the reference values of the rotor currents in d- and q-axis. Stator active and reactive power can be controlled by regulating the d, q-axis components of rotor current. POWER GRID SYSTEM In the past wind turbines were separated from the grid following grid faults. However, as of now, separation of wind turbines for voltage values 80% of the nominal voltage would lead to loss of an undesirable portion of power generation. Therefore, utilities now require an FRT capability as specified in Fig. 8. Wind turbine must stay connected even when the voltage at the point of common connection (PCC) with the grid drops to zero. The 150-ms delay shown in the figure accounts for the normal operating time of protection relays. The red solid line in Fig. 1 marks the lower voltage boundary rather than any characteristic voltage behavior. (11) Fig. 8. through requirements. Fig.8. Schematic diagram of a grid connected DFIG wind turbine system.
EEE6%2004042534.docx