Abstract: A proactive method and related wind turbine system are provided for reducing vibrations in the rotor blades when the rotor hub is locked against rotation. The method includes determining an initial blade orientation to wind direction and wind parameters for wind impacting the rotor blades. Based on the wind parameters and blade orientation, an angle of attack is determined for the rotor blades that will at least reduce vibrations expected to be induced in the blades from the current wind conditions. With a controller, the rotor blades are pitched to achieve the angle of attack using a pitch control system. The angle of attack is determined and the rotor blades are pitched from the initial blade orientation to the new angle of attack prior to vibrations being induced in the rotor blades.

Abstract: An electric power system includes an OLTC transformer including a plurality of primary and secondary windings inductively coupled to each other. The electric power system includes at least one on-load tap changer coupled to at least one of the primary and secondary windings that is selectively configurable to regulate the portion of the primary and secondary windings inductively coupled to each other. The electric power system also includes a plurality of buses coupled to the transformer and are positioned downstream therefrom. The electric power system further includes at least one processor coupled to the tap changer configured to regulate a voltage bandwidth of the tap changer as a function of estimated voltage values of at least one bus as estimated based on a priori values of power/current transmitted through each bus. The a priori values are substantially based on measured power/current transmission through the on-load tap changer.

Abstract: An electric power system includes an OLTC transformer including a plurality of primary and secondary windings inductively coupled to each other. The electric power system includes at least one on-load tap changer coupled to at least one of the primary and secondary windings that is selectively configurable to regulate the portion of the primary and secondary windings inductively coupled to each other. The electric power system also includes a plurality of buses coupled to the transformer and are positioned downstream therefrom. The electric power system further includes at least one processor coupled to the tap changer configured to regulate a voltage bandwidth of the tap changer as a function of estimated voltage values of at least one bus as estimated based on a priori values of power/current transmitted through each bus. The a priori values are substantially based on measured power/current transmission through the on-load tap changer.

Abstract: An electric power system including an on-load tap changing (OLTC) transformer is provided. The OLTC transformer includes a primary winding and a secondary winding. A portion of the at least one primary winding and at least one of the secondary windings are inductively coupled to each other. Further, the electric power system includes at least one on-load tap changer coupled to the at least one primary winding or the at least one secondary winding of the OLTC transformer. The on-load tap changer is configured to regulate the portion of the at least one primary winding or the at least one secondary winding that are inductively coupled to each other. Furthermore, the system includes at least one controller coupled to the on-load tap changer. The controller is configured to determine a permissible voltage range defined by a bandwidth around a voltage set-point at the at least one on-load tap changer, where the bandwidth is a function of one or more electrical network states.

Abstract: An electric power system including an on-load tap changing (OLTC) transformer is provided. The OLTC transformer includes a primary winding and a secondary winding. A portion of the at least one primary winding and at least one of the secondary windings are inductively coupled to each other. Further, the electric power system includes at least one on-load tap changer coupled to the at least one primary winding or the at least one secondary winding of the OLTC transformer. The on-load tap changer is configured to regulate the portion of the at least one primary winding or the at least one secondary winding that are inductively coupled to each other. Furthermore, the system includes at least one controller coupled to the on-load tap changer. The controller is configured to determine a permissible voltage range defined by a bandwidth around a voltage set-point at the at least one on-load tap changer, where the bandwidth is a function of one or more electrical network states.