A determination apparatus includes circuitry to receive a detection result of a time-varying physical quantity generated by rotation of a rotator attached to a rotation shaft, and rotation angle information of the rotator; and determine a rotation state of the rotator based on the detection result and the rotation angle information.

A method for detecting defects in a rotational element of a machine based on changes in measured vibration energy includes: (a) collecting vibration data over an extended period of time using vibration sensors attached to the machine; (b) processing the vibration data to generate a time waveform comprising processed vibration values sampled during sequential sampling time intervals within the extended period of time; (c) detecting multiple time blocks within the extended period of time during which the processed vibration values exhibit sustained increases at progressively increasing rates; and (d) generating alerts based on detection of the multiple time blocks during which the processed vibration values exhibit sustained increases at progressively increasing rates. The multiple time blocks may include a first time block during which the processed vibration values increase at a first rate, and a second time block occurring after the first time block during which the processed vibration values increase at a second rate that is greater than the first rate.

A signal processing method and apparatus quantifies signal “character” in the frequency domain from highly complex signals in a statistically consistent manner. Particular aspects focus on spectral density analyses such as skewness spectral density (SSD), kurtosis spectral density KSD), and probability spectral density (PDSD), among other types of spectral density. Applications of the inventive technique enable not only identification of signal characteristics, but also quantification of signal behavior in an explainable way. Higher orders of spectral densities are 1) physical and statistical, 2) convergent with boundable error, 3) integrable and relatable to the time-domain, and 4) typically differentiable.

A method (400) of determining blade tip deflection characteristics is applied to moving rotor blades (R.sub.1, R.sub.2) in a turbomachine (10) comprising a housing and rotor including a shaft with the rotor blades attached thereto and at least one proximity probe (202). The method (400) includes measuring ((402) a proximity signal caused by a presence of a proximate tip of a moving rotor blade (R.sub.1) and calculating (404) by a control module (212) a shaft Instantaneous Angular Position (IAP) as a function of time, and performing (410) an order tracking process which includes expressing (412) the measured proximity signal in the angular domain and resampling (414) the expressed proximity signal to render it equidistant in the angular domain. The method (400) includes performing (416) a pulse localisation process which includes filtering (418) the proximity signal yielding a complex-valued response, expressing (420) the complex-valued response in terms of a local amplitude and phase, and calculating (422) local phase shifts between each expressed signal and a reference signal.

A method of analyzing a vibratory signal derived from rotation of at least one moving part belonging to a rotary mechanism forming all or part of a drive train for transmitting drive torque, the rotary mechanism being fitted to an aircraft and the method comprising at least one first measurement step including measuring vibration in at least one direction and generating a vibratory signal representative of the operation of the rotary mechanism as a function of time, the first measurement step being performed by means of at least one vibration sensor; and at least one second measurement step including measuring an angular position of the moving part, the moving part having at least one degree of freedom to move in rotation about a respective axis of rotation Z. Such an analysis method makes it possible to determine at least one usable range for the vibratory signal.

A method of identifying a fault in a synchronous reluctance electric machine, the method including carrying out a first vibration measurement on a stator in a first radial direction of the stator; carrying out a second vibration measurement on the stator in a second radial direction of the stator; determining, on the basis of at least one of the first vibration measurement and the second vibration measurement, a first vibration frequency; determining, on the basis of the first vibration measurement and the second vibration measurement, a mode shape of the vibration at the first vibration frequency; and determining, on the basis that the first vibration frequency f.sub.b and the mode shape m fulfil the following barrier fault conditions:

f.sub.b=f.sub.r, and m=1

where f.sub.r is a rotation frequency of a rotor, that a flux barrier of the rotor is defect.

The disclosure is directed to a method comprising the steps: carrying out multiple measurements on a mechanical object, the measurements each differing by one or more parameters influencing the measurement; determining a spectrogram on the basis of the measurement data of the measurements and depending on a predefined parameter of the mechanical object; determining one or more excitations of the mechanical object; reproducing the excitations in the spectrogram.

Disclosed herein is a vibration monitoring and diagnosing system for monitoring conditions of a wind power generator and diagnosing a defective portion thereof using vibration characteristics obtained from acceleration sensors mounted to the wind power generator. A vibration-based defect detecting method may include: collecting vibration data of the wind power generator using the plurality of sensors; extracting a first characteristic value of a time domain based on the vibration data; extracting characteristic values in one or more frequency bands for a location of each sensor in a frequency domain or an envelope frequency domain if the first characteristic value is greater than a preset alarm setting value; and determining that a defect is present when at least one characteristic value of the characteristic values is greater than a preset normal value.

A state observation device (30) uses an ADC (37) to digitize a detection signal from a gap sensor (21) at a low-speed sampling period and uses a separation unit (38) to separate the digitized detection signal into vane detection signals considered to be for the detection of a vane of a compressor impeller and non-vane detection signals considered not to be for the detection of a vane. Further, the determination unit (39) extracts a vane peak detection signal considered to be for a vane peak by comparing a vane detection signal with vane detection signals corresponding to other vanes and non-vane detection signals, and a shaft vibration and tip clearance are determined as states of the compressor impeller on the basis of the extracted vane peak detection signal. Thus, the state observation device (30) is capable of observing the state of a rotary machine without carrying out high-speed sampling.

A system and method for receiving a plurality of first inputs from a transducer, where the plurality of first inputs correspond to vibrations of a rotational machine, and filtering the plurality of first inputs to derive a frequency of interest. The system and method then generates a sinusoidal signal at the frequency of interest and a pulse train of one or multiple pulses per revolution at the frequency of interest from the sinusoidal signal. The system and method further identifies a first pulse at a zero crossing within the pulse train and counts zero crossings to define blocks of data for use in time synchronous averaging calculations.