Hitachi, Ltd.

Japan Ae Power Systems Corporation

Toshiaki Rokunohe

Fumihiro Endo

Akira Yamagishi

Li Lu

Tatsuro Kato

Kenji Tsuchiya

Takeshi Ito

Tokio Yamagiwa

Tomohiro Moriyama

Jun Nukaga

Yasutomo Saito

Masaru Tatemi

Ayumu Morita

Hiroaki Hashimoto

Yasuaki Aoyama

Makoto Hirose

Satoshi Ichimura

Hajime Urai

Toyokazu Tanaka

Yoichi Oshita

Ryoichi Shinohara

Ryouichi Shinohara

Akira Nishimizu

Tomoaki Utsumi

Katsuhiko Shiraishi

Katsuji Shindo

Yoshio Hamadate

Takashi Omori

Hisao Inami

Hirohiko Yatsuzuka

Hisashi Urasaki

Yoshitaka Yagihashi

Shunji Ito

Hiroyuki Nakamichi

Hideaki Uchiyama

Masanori Otsuki

Kenji Anno

Akira Takahama

Hideyuki Miyahara

Kenji Aoyagi

Provided is an oil leakage detection apparatus by which oil leakage detection is performed even for colorless oil with high detection accuracy and without complicating the apparatus. The oil leakage detection apparatus of the invention includes a distance measurement unit configured to measure a distance to the oil-input machine, an ultraviolet light source configured to irradiate the oil-input machine with ultraviolet light, a color imaging unit configured to capture an image of the oil-input machine irradiated with ultraviolet light, an image processing unit configured to diagnose oil leakage of the oil-input machine based on the distance measured by the distance measurement unit and the captured image of the color imaging unit, and a display unit configured to display a processed image processed by the image processing unit. Further, an oil leakage detection method of the invention includes measuring a distance from an oil-input machine, irradiating the oil-input device with ultraviolet light, capturing an image of the oil-input machine irradiated with ultraviolet light, diagnosing oil leakage of the oil-input machine based on the measured distance and the captured image, and displaying a processed image after the diagnosis processing.

Work terminal, oil leakage detection apparatus, and oil leakage detection method

A diagnostic method of switchgear and a device of switchgear that allow regularly grasping a state with high accuracy with a simple configuration is provided. The diagnostic method of switchgear includes: obtaining signals from an acceleration sensor mounted to a switchgear and a load current flowing through the switchgear; determining a frequency to be focused from a spectrum analysis result of the signals from the acceleration sensor in an advance preparation phase of diagnosis of the switchgear, generating learning data using at least the frequency and the load current as feature values; and regularly diagnosing the state of the switchgear from the feature values obtained during diagnosis and the learning data during the diagnosis of the switchgear.

Diagnostic method of switchgear and device thereof

An oil leakage detector of the present invention includes an image processing unit wherein the image processing unit calculates the values of saturation and intensity of each pixel in the color image of the object after an ultra-violet light is irradiated thereon, draws an intensity-saturation characteristic line of the saturation expressed in an X-axis and the intensity expressed in a Y-axis, sets an upper limit and a lower limit of intensity of each saturation as a threshold value based on an area without oil adhesion on the surface of the object, and determines, in the intensity-saturation characteristic line, an area corresponding to a pixel group where the intensity exceeds the threshold value of the upper limit and a pixel group where the intensity falls below the threshold value of the lower limit, to be an oil leakage adhered area.

Oil leakage detector and oil leakage detection method and image processing unit

A symptom of malfunction regarding operating characteristics of a switch should be detected exactly. A switch operating characteristic monitoring device is comprised of a current sensor that measures a close command current of a switch, an auxiliary switch that outputs signals from at least two or more auxiliary contacts with reference to positions of a contactor, a measurement unit that measures signals from the current sensor and the auxiliary switch, a diagnosis unit that judges whether or not a malfunction occurs, and a display unit that displays a malfunction when a malfunction has been determined. A threshold is obtained in advance from multiple results of an opening/closing test performed beforehand. A calculation is made for characteristic times which are obtained from the close command current and signals from the auxiliary switch during actual operation of a circuit breaker. If a deviation is found by comparison with a threshold, a malfunction is determined.

Switch operating characteristic monitoring device, switch equipped with same, and switch operating characteristic monitoring method

There is provided a diagnosing device for an on-load tap changing apparatus of a transformer, which can diagnose the degradation degree of insulating oil at high accuracy by a relatively simple device configuration. A diagnosing device for an on-load tap changing apparatus has an insulating oil tank in which insulating oil is sealed, a changeover switching device that is disposed within the insulating oil tank and performs the tap changing operation of a tap winding, a tap selector that selects the tap position of the tap winding, and a polarity (transposition) changer that inverts the polarity of the tap winding or a winding connected to the tap winding. The diagnosing device includes an arc discharge light detector that detects arc discharge light that is emitted at changing the tap position of the tap selector. The degradation degree of the insulating oil is diagnosed based on the arc discharge light detected by the arc discharge light detector.

Diagnosing device for on-load tap changing apparatus, diagnosing method for on-load tap changing apparatus, and diagnosing device for transformer

A gas leak detection device includes a learning section, which has a correlation between a gas temperature inside gas pressure containers and a surface temperature of the gas pressure containers in a learning period corresponding to a current value flowing in the conductor, to make database, and a diagnosis section, which extracts a gas temperature corresponding to the measured current value and the surface temperature from the learning section in a diagnosis period, corrects a gas pressure value corresponding to an arbitrary surface temperature to a gas pressure value of a reference temperature using the extracted gas temperature, and detects a leak of the insulating gas based on the corrected gas pressure value.

Gas leak detection device and gas leak detection method

A system and method for detecting leakage oil with a high degree of accuracy while avoiding the complexity of the system and the influence of noise light comprise: ultraviolet light sources arranged to irradiate an oil-filled device from a plurality of different incidence angles, and are switched on and off at the respective incidence angles in sequence, and include a wavelength exciting oil; an imaging device to photograph the oil-filled device irradiated with ultraviolet light emitted from the ultraviolet light sources when the ultraviolet light sources are switched on; a recorder to record respective images photographed by the imaging device; and a display to display the respective images. The respective images are compared, a site where a light emitting position does not change always is judged as a leakage oil site, and a site emitting light or not emitting light occasionally is judged as a noise light site.

Leakage oil detector system and method

The invention is intended to provide a circuit breaker or a circuit breaker operating method enabling a current interruption action to be performed efficiently. A circuit breaker is characterized in that includes a fixed contact and a movable contact that comes in and goes out of contact with the fixed contact; a main circuit conductor that is electrically connected to the fixed contact and the movable contact; an operating mechanism including a mover configured by concatenating permanent magnets or magnetic materials alternately having opposite N and S magnetic polarities along the direction of motion axis of the movable contact and magnetic poles disposed to face the N and S magnetic polarities of the mover and wound with windings; a current detector that detects a current flowing through the main circuit conductor; and a control device that varies the amount of a current to be supplied to the windings of the magnetic poles, depending on a current value detected by the current detector.

Circuit breaker and circuit breaker operating method

Oil leakage detector and oil leakage detection method

An object is to provide a switchgear having a simple structure. To solve the problem, a switchgear according to the invention is characterized by having a fixed side electrode, a movable side electrodeconfigured to come into contact with or separate from the fixed side electrode, and an operating mechanism configured to allow drive force for movement of the movable side electrodeto be generated, wherein the operating mechanism for operating the movable side electrodeincludes one operating mechanism, and the one operating mechanism allows the movable side electrodeto stop at three or more positions.

Switchgear

The present invention is provided to satisfy insulation and conductivity performance requirements, to reduce the size of a gas insulated bus, and also to make conditioning for a particle more reliable. In a gas insulated bus having a conductor supported in a cylindrical metal container via an insulator, insulating gas being contained in the metal container, the metal container has an expanded diameter part formed over a given range in an area of the metal container in which the insulator is positioned and a reduced diameter part formed over the entire area of the metal container except for the expanded diameter part. Thus, when the temperature of the insulator increases during conduction, heat from the insulator is transferred to the metal container via a large space in the expanded diameter part and released to the air through a large outer surface of the expanded diameter part of the metal container.

Gas insulated bus and particle removal method for gas insulated bus

In the measurement of partial discharge, a voltage detected by an antenna is input to a spectrum analyzer and a phase difference between an operating voltage and a power supply of the spectrum analyzer is obtained by phase domain analysis using the spectrum analyzer. Based on the phase difference and the voltage phase shift associated with the input impedance of a signal converter circuit, the time axis displayed on the screen of the spectrum analyzer is compensated. After the compensation has been carried out, the voltage detected by the antenna is input into the spectrum analyzer and the partial discharge pattern which synchronizes with the operating voltage is measured by phase domain analysis using the spectrum analyzer.

Method and system for measuring partial discharge

In a gas-insulated switchgear tank in which an electric insulating characteristic is improved by a gas, and which has a vacuum circuit-breaker, a disconnecting switch, and a container in which container the vacuum circuit-breaker and the disconnecting switch are arranged and an inside of which container is adapted to be hermetically sealed and filled with the gas in such a manner that the vacuum circuit-breaker and the disconnecting switch are at least partially surrounded by the gas, the gas includes Nand O.

Gas-insulated switchgear tank

A gas insulated switchgear capable of performing maintenance and inspection of a breaker without shutting down a bus line includes a first case containing a breaker and having a bushing for leading a load and a second case containing a plurality of disconnectors and having a plurality of bushings for leading a plurality of bus lines to be connected to the disconnectors. The first case and the second case are connected to each other through a gas partition spacer.

Gas insulated switchgear

Growing community of inventors

Tokyo, Japan

Toshiaki Rokunohe