Toshiba Mitsubishi-Electric Industrial Systems Corporation

The University of Tokyo

Kabushiki Kaisha Toshiba

Tmeic Corporation

Toshiba Industrial Products and Systems Corporation

Tetsuo Yoshimitsu

Toshihiro Tsuda

Yuichi Tsuboi

Kotaro Mura

Kunihiko Hidaka

Akiko Kumada

Hisatoshi Ikeda

Satoshi Hiroshima

Tatsuya Hirose

Masaaki Furukawa

Takayuki Sakurai

Kodai Ushiwata

Hiroyuki Ogawa

Yu Yamashita

Takahiro Imai

Shinsuke Kikuta

Yuji Yamamoto

Shinichiro Yamada

Yoshihiro Ishikawa

Hirotake Nakaji

Teruo Kanekawa

Masayuki Hikita

Masahiro Kozako

Takahisa Ueno

Jintong Sun

Hirotsugu Tsutsui

Kiyoshi Umezu

Tomomi Ikegami

Hiromitsu Hirai

Masahiro Takeno

A resin producing method is a method of producing a resin with which an insulating structure formed on an outer peripheral portion of a conductor is impregnated. The resin producing method includes a dispersion liquid mixing step of mixing an epoxy resin and a dispersion liquid in which a nanofiller is dispersed in a reactive diluent that reduces a viscosity of the epoxy resin by reacting with the epoxy resin, and a curing agent mixing step of mixing a composition produced by the dispersion liquid mixing step, with a curing agent that cures the epoxy resin. The epoxy resin includes, for example, an alicyclic epoxy resin.

Method of producing resin and method of producing insulating structure

A resin producing method is a method of producing a resin with which an insulating structure formed on an outer peripheral portion of a conductor is impregnated, the method including: a filler mixing step of mixing a nanofiller at a ratio of 15 wt % or more with an epoxy resin to form a mixture; a shear mixing step of causing the mixture to be subjected to shear mixing; a diluent mixing step of mixing a reactive diluent that reduces a viscosity of the epoxy resin, with the mixture after the shear mixing step; and a curing agent mixing step of mixing an acid anhydride curing agent with the mixture after the diluent mixing step.

An impulse voltage generation device comprises: a high voltage generator to generate high DC voltage; a capacitor that is disposed in parallel to the high voltage generator and can be charged to a high voltage state; a power semiconductor switch that is placed at an output side of the high voltage generator and in series to the high voltage generator and is designed to shut off or allow electricity output from the high voltage generator; a function generator to output changes over time of impulse voltage to be applied to the test target; a current detector to detect output current; and an overcurrent protection circuit that is configured to conduct analog-to-digital conversion at sampling intervals sufficiently shorter than the application intervals when receiving a current signal from the current detector, monitors values of the output current, and to block output from the function generator to the power semiconductor switch if it is determined that there is an abnormality.

Impulse voltage generation device, and power semiconductor switch protection method

A three-dimensional surface potential distribution measurement system for measuring a surface potential of a measurement object comprises: a laser light source; a Pockels crystal exhibiting Pockels effect in which a refractive index changes depending on potential difference between the first end surface and the second end surface; a mirror disposed so as to be attached stationarily to the second end surface of the Pockels crystal; a photodetector to detect a light intensity of the laser light corresponding to the potential difference of the Pockels crystal; a housing that holds those elements; a three-dimensional motion-driver capable of three-dimensionally moving the housing; and a driving controller that controls the three-dimensional motion-driver.

Three-dimensional surface potential distribution measurement system

A producing method is for an electrical insulating structure to cover an outer surface of a to-be-insulated object. The method comprises: a tape production step of producing a main insulation tape by using a nanoparticle-containing joining macromolecular polymer; a taping step of winding a main insulation tape on outside of the to-be-insulated object to form a main insulated part; a vacuum drawing step, which is performed after the taping step, of vacuum drawing the tape-wound to-be-insulated object; and an impregnation step, which is performed after the vacuum drawing step, of injecting a impregnating macromolecular polymer to impregnate the main insulated part therewith.

Electrical insulating structure producing method, electrical insulating structure and rotating electrical machine

A producing method is for an electrical insulating structure covering an outer surface of a to-be-insulated object. The electrical insulating structure producing method comprises: a sheet production step of producing a main insulating sheet in which nanoparticles have been mixed; a cutting step in which the main insulating sheet is cut into main insulation tapes; a taping step of winding each of main insulation tapes on outside of the to-be-insulated object to produce a tape-wound to-be-insulated object in which a main insulated part is formed; a vacuum drawing step of vacuum drawing the tape-wound to-be-insulated object; an impregnation step of injecting a impregnating macromolecular polymer to impregnate the main insulated part in the tape-wound to-be-insulated object, and a solidifying step of raising the temperature of the insulated part to solidify the macromolecular polymer containing the nanoparticles.

This electrical tree test method is a method for testing for electrical trees in an insulating member including a mica insulation applied to an electrical conductor. The method comprises: an assembly setting step of setting an electrode setting assembly to the outside of the mica insulation; an impregnation step of impregnating the mica insulation with synthetic resin after the assembly setting step; a removal step of removing components of the electrode setting assembly, except an electrode structure, after the impregnation step; a power supply connecting step of connecting, after the removal step, the electrical conductor and the electrode structure to a power supply in order to apply a voltage between the electrical conductor and the electrode structure; and a voltage applying step of applying a voltage between the electrical conductor and the electrode structure, after the power supply connecting step.

Electrical tree test method, electrode structure, and electrode setting assembly

A producing method for an electrical insulating structure that covers an outer surface of a to-be-insulated object is provided. The method comprises: a taping step of winding a main insulation tape on outside of the to-be-insulated object; a spraying step of spraying nanoparticles onto the outer surface of the wound main insulation tape; a vacuum drawing step of vacuum drawing the tape-wound to-be-insulated object; and an impregnation step of injecting a nanoparticle-containing impregnating macromolecular polymer in which nanoparticles have been kneaded to impregnate the to-be-insulated object therewith. In the spraying step, microcapsules, which contain the nanoparticles and are able to release the nanoparticles before the impregnation step, are sprayed.

Producing method for electrical insulating structure, electrical insulating structure and rotating electrical machine

A partial discharge measurement device includes: an impulse voltage application unit; a measurement control unit; and first and second partial discharge detection unit. The measurement control unit includes: a first and a second detector level partial discharge counting unit; and a partial discharge resistance evaluation unit. Each of the first and the second detector level partial discharge counting units outputs a first or second detection signal when the first or second detection signal exceeds a predetermined specified value. The partial discharge resistance evaluation unit counts the number of occurrences of partial discharge based on an output from the first and second detector level partial discharge counting unit, and regards the impulse voltage value at which the count value has reached a predetermined value as a partial discharge inception voltage under the repeated impulse voltage application.

Partial discharge measurement device

A water-tree resistance evaluation material including: a material selection selecting a candidate insulation material; a test carrying out a water tree test on a test piece having electrode holes formed on a first surface; and a candidate insulation material evaluation evaluating characteristics of the candidate insulation material, including progress and speed of a water tree. The test includes: a system and condition setting for setting a test system; a voltage application for grounding a ground-side electrode that is immersed in the ground-side aqueous solution, while applying an AC voltage to an application-side electrode that is immersed in the application-side aqueous solution; a measurement step; and a period determination for determining whether a test period has exceeded a predetermined period.

Water-tree resistance evaluation method, insulation design method, and rotary electric machine

A three-dimensional surface potential distribution measurement apparatus includes: a laser light source; a Pockels crystal; a mirror; a light detector; a support structure which supports the aforementioned elements while maintaining a relative positional relationship therebetween; a movement driver which can move the support structure three-dimensionally; a rotary driver which supports the test object and can rotate the test object about an axis extending in a longitudinal direction of the test object; and a drive controller which controls the movement driver and the rotary driver. The drive controller coordinates a driving operation by the movement driver and by the rotary driver while maintaining a gap between the second end face of the Pockels crystal and a surface of the test object at a predetermined value such that the second end face of the Pockels crystal approaches all the surfaces of the electric field reduction system on the test object.

Three-dimensional surface potential distribution measurement apparatus

A water tree testing apparatus using a flat test piece comprising a candidate insulation material an d having a first surface having a plurality of electrode holes formed therein has: a liquid-permeable conductive first permeable member that is attached to the first surface and covers the electrode holes; a liquid-permeable conductive second permeable member that is attached to a second surface that is opposite side from the first surface, and extends along the second surface as to face the first permeable member with the test piece therebetween; a first water tank for immersing the first surface in the first aqueous solution; a second water tank for immersing the second surface in the second aqueous solution; a first electrode, and a second electrode.

Water tree testing method and water tree testing apparatus

A surface-potential distribution measuring device includes: a laser light source; a Pockels crystal; a mirror; a photodetector that detects light intensity of the laser beam reflected by the mirror; a holding and mounting part that holds and moves the Pockels crystal; a voltage correction database; and a calculation unit that identifies an input voltage corresponding to a testing output voltage as a surface potential of the electric-field-reduction system. The Pockels crystal is formed in such a way that a size of a cross section of the Pockels crystal that is perpendicular to an axial direction changes along the axial direction. The holding and mounting part has a protection unit to protect a structure of the Pockels crystal, a movement unit to that moves the Pockels crystal in order to measure a surface potential of the electric-field-reduction system, and a drive control unit to control the movement unit.

Surface potential distribution measuring device

In a surface potential distribution measuring device for an electric field reduction system of a rotating electrical machine, a Pockels crystal is used between a laser and the surface (test location) of the electric field reduction system. Light intensity of a laser beam reflected on a mirror provided between the Pockels crystal and the test location corresponds to an output voltage that is the voltage difference between the first end surface and the second end surface of the Pockels crystal. Even when an inverter voltage is generated, by using a light detector having a frequency band capable of following the high frequency components of the inverter pulse voltage, the light intensity is detected by the light detector. Therefore, from the light intensity (output voltage), the surface potential distribution measuring device can measure the surface potential of the electric field reduction system in which an inverter pulse voltage is generated.

Surface potential distribution measuring device and surface potential distribution measuring method

An impulse voltage generator uses a predetermined rectangular waveform signal and a high voltage to generate an impulse voltage. The high voltage is obtained by boosting an instruction voltage of the rectangular waveform signal on a per-cycle basis. A partial discharge frequency calculation section receives detection signals based on partial discharges occurring in an object to be measured by the application of the impulse voltage and counts the detection signal on a per-cycle basis as a partial discharge frequency. An application voltage signal observation circuit observes an application voltage signal indicating the impulse voltage applied to the object to be measured. In a first cycle in which the partial discharge frequency reaches a specified frequency or more, a voltage value acquiring section sets, as a partial discharge starting voltage, the peak value of the voltage indicated by the application voltage signal output from the application voltage signal observation circuit.

Growing community of inventors

Tokyo, Japan

Tetsuo Yoshimitsu