A method for monitoring a status of a reduction gear of a gas turbine includes the steps of: obtaining measurements of parameters accomplished during an operating phase of the gas turbine, these parameters including temperatures of a lubricating oil of the reduction gear at the inlet and at the outlet of the reduction gear, a parameter representing a speed of the gas turbine, as well as at least one context parameter; selecting measurements; normalizing temperatures of the lubricating oil using the measurements of the context parameter; evaluating a thermal efficiency of the reduction gear by using a physical model defining the thermal efficiency based on a difference between the temperature of the lubricating oil; and determining a status of the reduction gear depending on a step of comparing the evaluated thermal efficiency with respect to a reference signature.

A method of identifying a fault in a system of gears in a wind turbine is provided. The method determines two or more centre harmonic frequency amplitudes according to vibrations of the system of gears and determines a plurality of sideband amplitudes of each of the centre harmonic frequency amplitudes. Further, the method sums the centre harmonic frequency amplitudes to calculate a total centre harmonic frequency amplitude and sums each of the sideband amplitudes of the centre harmonic frequency amplitudes to calculate a total sideband amplitude. The method then determines a value indicative of damage incurred by the system of gears based upon the first centre harmonic frequency amplitude and the average sideband amplitude.

A method of identifying a fault in a system of gears in a wind turbine is provided. The method determines two or more centre harmonic frequency amplitudes according to vibrations of the system of gears and determines a plurality of sideband amplitudes of each of the centre harmonic frequency amplitudes. Further, the method sums the centre harmonic frequency amplitudes to calculate a total centre harmonic frequency amplitude and sums each of the sideband amplitudes of the centre harmonic frequency amplitudes to calculate a total sideband amplitude. The method then determines a value indicative of damage incurred by the system of gears based upon the first centre harmonic frequency amplitude and the average sideband amplitude.

An abnormality of a gear is more appropriately predicted. An abnormality prediction device of the present disclosure is used in a feeding device including a driving section, a gear connected to the driving section, and a detection section configured to detect a position of a medium fed in accordance with driving of the gear, and intermittently feeding the medium. The abnormality prediction device acquires detection information regarding a feed amount of the medium based on the position of the medium detected over time by the detection section, decomposes the acquired detection information into a trend component regarding a moving average of the gear, a cycle component based on a cycle of the gear, and a random component obtained by excluding the trend component and the cycle component, obtains an abnormality level of the gear based on the cycle component obtained by the decomposition, and outputs the obtained abnormality level.

An abnormality of a gear is more appropriately predicted. An abnormality prediction device of the present disclosure is used in a feeding device including a driving section, a gear connected to the driving section, and a detection section configured to detect a position of a medium fed in accordance with driving of the gear, and intermittently feeding the medium. The abnormality prediction device acquires detection information regarding a feed amount of the medium based on the position of the medium detected over time by the detection section, decomposes the acquired detection information into a trend component regarding a moving average of the gear, a cycle component based on a cycle of the gear, and a random component obtained by excluding the trend component and the cycle component, obtains an abnormality level of the gear based on the cycle component obtained by the decomposition, and outputs the obtained abnormality level.

There is provided a sensor including a sensor element, a substrate on which the sensor element is disposed, and a casing that accommodates the substrate. The casing has a doughnut shape, and has a connecting portion for externally connecting a wire. In a doughnut-shaped internal space of the casing, the substrate is disposed, and the wire is disposed in the connecting portion from a side of the substrate far from the connecting portion. A central cylinder portion is interposed between the substrate and the wire.

There is provided a sensor including a sensor element, a substrate on which the sensor element is disposed, and a casing that accommodates the substrate. The casing has a doughnut shape, and has a connecting portion for externally connecting a wire. In a doughnut-shaped internal space of the casing, the substrate is disposed, and the wire is disposed in the connecting portion from a side of the substrate far from the connecting portion. A central cylinder portion is interposed between the substrate and the wire.

A system includes a chip detector that includes a magnet, the chip detector operable to collect a plurality of chips in a lubricant flow. The system also includes a radiation sensor associated with the magnet and operable to detect radiation emitted by at least some of the plurality of chips collected by the magnet.

A system includes a chip detector that includes a magnet, the chip detector operable to collect a plurality of chips in a lubricant flow. The system also includes a radiation sensor associated with the magnet and operable to detect radiation emitted by at least some of the plurality of chips collected by the magnet.

A detection system includes a loadcell connected to a gear and motor of a crystal puller apparatus to measure force applied to the gear in a time domain. The data is analyzed though a Fourier transform to obtain data in the frequency domain. The frequency domain data includes an amplitude which corresponds to mechanical wear of the gear. The time domain data is compared against a threshold amplitude to determine if the gears have mechanical wear such that preventative maintenance can be performed on the motor.