Power regulation of roll transmission system to satisfy coarse rolling requirement in the continuous hot rolling line with small power

The paper presents the research of symmetrical and unsymmetrical grid fault ride-through for a wind turbine system. When a fault occurs, the rotor side converter is set to be out of operation and the rotor windings of the generator is connected to resistors in order to maintain the synchronous operation with the grid. While the grid side converter is regulated so as to generate reactive power to support the grid during the grid fault. The simulation results in Matlab-Simulink-Plecs environment show that the presented fault ride-through method obtains good transient responses when the system is undergo the symmetrical and unsymmetrical fault.