Abstract: A method of monitoring vibrations in a blade structure of a turbine including generating signals from a sensor located adjacent to a radial outer edge of the blade structure to sense passage of targets located on the blade structure. The sensor is mounted eccentrically and the signals are obtained with the sensor located at different angular positions. In a first aspect of the invention, the signals from the sensor are used to determine a target slope angle of a target on a first turbine blade during operation of the turbine. In a second aspect of the invention, the signals from the sensor are used to position the sensor in response to a sensed variation in the axial position of the target on the first turbine blade.

Abstract: A method of monitoring vibrations in a blade structure of a turbine including generating signals from a sensor located adjacent to a radial outer edge of the blade structure to sense passage of targets located on the blade structure. The sensor is mounted eccentrically and the signals are obtained with the sensor located at different angular positions. In a first aspect of the invention, the signals from the sensor are used to determine a target slope angle of a target on a first turbine blade during operation of the turbine. In a second aspect of the invention, the signals from the sensor are used to position the sensor in response to a sensed variation in the axial position of the target on the first turbine blade.

Abstract: A method for monitoring turbine blade vibrations comprises the step of transmitting a continuous wave of microwave energy toward a rotating row of blades. Each passage of an individual blade tip through the path of the continuous wave produces a signal indicative of the time at which each passage occurs. The signal is then monitored and analyzed to detect blade vibrations. The signal can be based on a standing wave or a reflected wave.

Abstract: Method of attaching a target for use in a system for monitoring the vibration of a plurality of shrouded turbine blades to a shroud segment. The target includes a shim plated with a highly conductive material for inducing variations in eddy currents generated by stationary sensors, as part of a system for monitoring blade vibrations. The target is spot welded to the shroud segment of the turbine blades at the turbine site using portable welding equipment, providing effective and low cost installation.

Abstract: A system for monitoring the vibration of a plurality of shrouded turbine blades carried by a rotor and configured in a row includes a stationary sensor for inducing eddy currents in each shroud segment as each shroud segment passes the sensor. A target is located on each shroud segment for causing variations in the induced eddy currents. The sensor is responsive to the induced eddy currents to produce an output signal containing information corresponding to the time of arrival of the target at the sensor. Another sensor is provided for producing a pulse once per rotor revolution. A blade vibration monitor is responsive to the output signal and the once per rotor revolution pulse to extract blade vibration information therefrom.