Turbine generator faults can be detected by receiving a current signal from the turbine generator, and synchronously sampling the current signal to obtain a set of current signal samples that are evenly spaced in the phase domain, in which phase differences between adjacent current signal samples in the set of current signal samples are substantially the same. The process includes generating a frequency spectrum of the current signal samples, identifying one or more excitations in the frequency spectrum, and detecting a fault in the turbine generator based on the one or more excitations in the frequency spectrum.

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Detecting Faults in Turbine Generators

A wind turbine generator fault detection method is described. The method includes acquiring current data from a wind turbine generator during operation, determining frequency demodulated signals and amplitude demodulated signals by frequency demodulating and amplitude demodulating the current data, resampling the frequency and amplitude demodulated signals corresponding to the current data, monitoring a frequency spectra of the resampled frequency and amplitude demodulated signals corresponding to the current data to identify one or more excitations in the frequency spectra. In response to identifying one or more excitations in the frequency spectra at one or more of the variable fault characteristic frequencies, the method includes generating and transmitting an alert that indicates that a wind turbine generator fault is detected.

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Detecting Faults in Wind Turbines

A system includes an encoder to monitor a machine and generate an encoder output signal indicative of at least one of the motion or position of the machine. A combiner can be configured to receive the encoder output signal from the encoder and to receive machine diagnostic data from at least one other sensor. The combiner can combine the machine diagnostic data with the encoder output signal to provide a combined signal that includes the machine diagnostic data synchronized with the at least one of the motion or position of the machine. An output stage can provide the combined signal to a remote system.

Machine diagnostic encoder

The invention discloses a combined vibration damper of a screw drill complete machine test-bed and a manufacturing method thereof. The combined vibration damper comprises a vibration attenuation base which comprises a loading system base, a first clamping system base and a second clamping system base, wherein the loading system base is arranged on an equipment foundation in a rigidity way; the first clamping system base and the second clamping system base are connected into a whole through a bolt and are arranged on the equipment foundation through a rubber vibration attenuation block; an interval of 30-50 mm is reserved between the loading system base and each clamping system base; the first clamping system base and the second clamping system base are respectively internally provided with a plurality of cubic cavities with an equal size; the volume of each cubic cavity is 0.1-0.2 cubic meter; discrete type balance weight sand is respectively filled into the cubic cavities, and the filling efficiency is 80-90 %; and the weight of the balance weight sand is 25-35 % of the total weight of the whole device. The test-bed is capable of restraining resonance and testing precisely in the testing process by the combined vibration damper, and the usage precision of surrounding working devices is not affected.

Combined vibration damper of screw drill complete machine test-bed and manufacturing method thereof

Measurement of bladed rotors and, more particularly, speed measurement of bladed rotors in a turbine engine using microwave probes is described. In one embodiment, an apparatus for measuring bladed includes a microwave sensor that radiates a microwave signal toward a bladed rotor and receives a reflected microwave signal from the bladed rotor, a radio frequency module that generates the microwave signal radiated by the microwave sensor and down-converts the reflected microwave signal into a down-converted signal, and a main processing module configured to generate an output pulse train signal representative of a speed of the bladed rotor based on the down-converted signal. In another embodiment, a method for measuring bladed rotors is described including radiating a microwave signal, receiving a reflected microwave signal, down- converting the reflected microwave signal, and generating an output pulse train signal representative of a speed of a bladed rotor based on the down-converted signal.

Measurement of bladed rotors

Vibration analysis is performed on a machine having a variable frequency drive by using a tachometer to monitor rotational speed of the drive shaft and a logic device to calculate speed parameters associated with the drive shaft using the tachometer data. The speed parameters include a maximum speed, a minimum speed, and an average speed of the drive shaft. By correlating the vibration spectra of the motor drive with the speed parameters, machine faults can be identified based upon the energy distribution in the spectra. Further, vibration waveforms from two or more locations on the machine can be sequentially acquired through synchronous triggering by using a pulse edge of a stable tachometer signal. The waveforms can be compared to determine a phase difference to help in identifying any machine faults that may be present.

System and method for vibration analysis and phase analysis of vibration waveforms using dynamic statistical averaging of tachometer data to accurately calculate rotational speed

PROBLEM TO BE SOLVED: To perform vibration analysis and phase analysis of vibration waveforms using dynamic statistical averaging of tachometer data to accurately calculate rotational speed.SOLUTION: Vibration analysis is performed on a machine having a variable frequency drive by using a tachometer to monitor rotational speed of a drive shaft and a logic device to calculate speed parameters associated with the drive shaft using tachometer data. The speed parameters include a maximum speed, a minimum speed, and an average speed of the drive shaft. By correlating vibration spectra of a motor drive with the speed parameters, machine faults can be identified based upon energy distribution in the spectra. Further, vibration waveforms from two or more locations on the machine can be sequentially acquired through synchronous triggering by using a pulse edge of a stable tachometer signal. The waveforms can be compared to determine a phase difference to help in identifying any machine faults that may be present.SELECTED DRAWING: Figure 1

Nidhin Anthony Jose

Papers

System and method for vibration analysis and phase analysis of vibration waveforms using dynamic statistical averaging of tachometer data to accurately calculate rotational speed

Vibration analysis system