Mitsubishi Electric Corporation

Sumco Corporation

Teijin Limited

Ushio Denki Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Oki Electric Industry Co., Ltd.

Proterial, Ltd.

Sumitomo Mitsubishi Silicon Corporation

Freund Corporation

Umetoku Co., Ltd

Daido Chemical Co., Ltd.

Hitachi Metals, Ltd.

Satoshi Murakami

Ryota Kondo

Masaki Yamada

Takaaki Takahara

Naohisa Uehara

Nobuyuki Morimoto

Akihiko Endo

Hideki Nishihata

Yoshihiro Takeshima

Yuta Komatsu

Akira Nakagawa

Hiroyasu Iwabuki

Osafumi Hidaka

Takashi Kaneyama

Kazutoshi Awane

Ryosuke Kobayashi

Hidehiko Kinoshita

Yoshiaki Ishiguro

Nobuhiro Kihara

Kimihiko Tanaya

Kenichi Inoue

Takeshi Nakatani

Noriyuki Wada

Kiyoshi Imai

Hiroyuki Higashino

Yusuke Naruse

Shigeru Umeno

Satoshi Ishibashi

Yoshinori Koshida

Takahiro Okanoue

Yuichi Muramoto

Takafumi Mizojiri

Kei Hayase

Yuuya Tanaka

Yoshihiro Kanahashi

Mutsuhito Yoneta

Mitsuyasu Kunihiro

Michisuke Ohe

Susumu Maruo

Hiroto Mizutani

Shuho Koseki

Masanori Sato

Hajime Toyoda

Akinu Nakabayashi

Tamio Motoyama

Kengo Nishimura

Hirotaka Fujii

Shusaku Tanabe

Tatsuya Shouji

Tomoyuki Taniguchi

Katsuhiro Obata

Yoshikazu Suzuki

Makoto Akashi

Yoshifusa Tachimori

Naoki Hayashi

Toshifumi Miyamoto

Toru Otomo

Nobuhiro Ikeda

Kousuke Uda

Takashi Ogisu

Yoshito Saji

A feedback control unit includes a controller which calculates a duty ratio for switching elements on the basis of a command value and a detection value of electrical information. A continuous/discontinuous current mode distinguishment unit includes a duty ratio increase/decrease distinguishment unit which performs distinguishment between increase and decrease in the duty ratio, and an output voltage detection value increase/decrease distinguishment unit which performs distinguishment between increase and decrease in a detection value of a voltage of second terminals. If the duty ratio has decreased and the detection value of the voltage has increased, or if the duty ratio has increased and the detection value of the voltage has decreased, the continuous/discontinuous current mode distinguishment unit determines that an operation mode is a discontinuous current mode, and feeds back a result of the determination to the feedback control unit.

Device for controlling power conversion circuit

A power conversion device according to the present disclosure has one end connected to a DC voltage source and another end connected to a load, and includes: an inverter circuit which converts DC voltage from the DC voltage source to AC voltage to be outputted to the load, and includes a leg in which an upper arm and a lower arm each having a switching element, and a resistor, are connected in series, and a smoothing capacitor connected in parallel to the leg; a current detection circuit which detects voltage across the resistor, to detect current of the resistor; and a control circuit which controls the inverter circuit. The control circuit corrects the current value detected by the current detection circuit, using an operation condition of the inverter circuit, and controls the inverter circuit using the corrected current value. Thus, error occurring in the current detection circuit can be corrected.

Power conversion device

A power conversion device and a motor system according to the present disclosure comprises an inverter circuit which is connected to a motor, a switch circuit, and a control circuit. The power conversion device and the motor system are characterized in that the inverter circuit and the switch circuit are capable of two-level operation and three-level operation, and the control circuit switches between the two-level operation and the three-level operation on the basis of the motor torque command and the rotational speed command. As a result, it is possible to reduce the total loss in the power conversion device and the motor.

Power conversion device and motor system

A method for manufacturing a forged article, capable of improving the durability of a die for forging is provided. The method, includes forging a steel material, by using a die, by spraying or applying a water-soluble polymer lubricant containing 0.01 to 0.98 mass % of a water-soluble sulfate onto a working surface of the die, the die being made of a raw material having a constituent composition of by mass %, of 0.4 to 0.7% of C, 1.0% or less of Si, 1.0% or less of Mn, 4.0 to 6.0% of Cr, 2.0 to 4.0% of (Mo+½W), 0.5 to 2.5% of (V+Nb), 0 to 1.0% of Ni, 0 to 5.0% of Co, 0.02% or less of N, and a remnant composed of Fe and impurities, and having hardness of 55 to 60 HRC, and the die including a nitrided layer or a nitrosulfidized layer on the working surface thereof.

Method for manufacturing forged article

An inverter is provided for driving a motor. A first capacitor, and a second capacitor including capacitors connected in series, are connected in parallel to a DC power supply. A switch circuit having switching elements is connected between the inverter and the second capacitor. A control circuit is provided for controlling the inverter and the switch circuit. The control circuit performs control to switch the switch circuit so as to supply current from the second capacitor to the inverter during 3-level operation, and supply current from both of the first capacitor and the second capacitor to the inverter during 2-level operation.

A period from when switching elements S, Sat first diagonal positions in a full-bridge inverter are turned off at the same time to when switching elements S, Sat second diagonal positions are turned on at the same time, is defined as T, and a period from when the switching elements S, Sat the second diagonal positions are turned off at the same time to when the switching elements S, Sat the first diagonal positions are turned on at the same time, is defined as T. With a total length of Tand Tset to be constant, the lengths of Tand Tare controlled to be changed every switching cycle.

A light source unit includes a plurality of LED elements; an LED substrate that comprises a plurality of subdivided regions arrayed in a circumferential direction at least at an outwardmost locus as viewed from a direction perpendicular to the mounting surface; and cooling member(s) which are provided at surface(s) on a side opposite the mounting surface of the LED substrate and at which provided at each of the plurality of subdivided regions there are inlet port(s) for flow thereinto of cooling medium for cooling LED element(s), outlet port(s) that are for discharge of cooling medium and that are disposed more toward a center of the LED substrate than inlet port(s) as viewed from the direction perpendicular to the mounting surface of the LED substrate, and flow passage(s) which connect inlet port(s) and outlet port(s) and through interior(s) of which cooling medium flows.

Light source unit and light irradiation device

A power conversion device includes: a main body including a substrate to which a power conversion unit and a coil are provided; and a first heat dissipation portion which holds the substrate and dissipates heat of the substrate, wherein the substrate is formed by one sheet, the coil is formed integrally with the substrate, the first heat dissipation portion is fixed to a substrate first surface of the substrate, a heat dissipation second surface of the first heat dissipation portion has a coil cooling portion opposed to and abutting on a part where the coil is formed, of the substrate.

Power converter

A magnetically coupled reactor and a DC/DC converter are provided between a DC power supply and an inverter. A first smoothing capacitor is provided between the DC power supply and the coupled reactor. A second smoothing capacitor is provided between the DC/DC converter and the inverter. A controller is provided in order to control switching operations of the inverter and the DC/DC converter. The controller causes semiconductor switching elements composing upper and lower arms of the DC/DC converter to perform complementary operations so as to be alternately turned on/off, and causes left and right legs to operate with their switching phases shifted from each other, thereby electric charges stored in both smoothing capacitors are discharged by energy loss in the coupled reactor and the DC/DC converter.

Power conversion device with controller to discharge smoothing capacitors

The light irradiation device includes a light source supporter having a tubular shape is closed on a side of one end, a plurality of light-emitting elements placed on an outer wall surface of the light source supporter, a tubular body extending inside the light source supporter in an axial direction of the light source supporter, a first flow channel formed between the tubular body and the light source supporter and having an annular shape when viewed from the axial direction; and a second flow channel formed inside the tubular body, wherein the first flow channel and the second flow channel communicate with each other on a side of one end of the light source supporter, and the tubular body contains a material having a thermal conductivity lower than a thermal conductivity of a material constituting an outer wall of the first flow channel.

Light irradiation device

A power conversion device including: a reactor formed such that a DC winding and a plurality of coupled windings are wound around one magnetic body, one end of the DC winding is connected to a voltage source, one end of each of the plurality of coupled windings is connected to another end of the DC winding, another end of each of the plurality of coupled windings is connected to each intermediate connection point between a plurality of upper and lower arms composed of switching elements, and magnetic fluxes generated by currents flowing through the DC winding and the coupled windings merge with each other in the same direction; and a control device for controlling the switching elements, wherein the upper arms or the lower arms are controlled by in-phase driving or interleave driving on the basis of the duty of switching operation.

Power conversion device with in-phase and interleave driving based on determination of duty ratio

A resonant inverter includes: an input capacitor; an inverter; a snubber circuit; a transformer having a primary winding connected to an AC end of the inverter; a resonant coil, a resonant capacitor, and a current sensor on the secondary winding side of the transformer; and a control unit, wherein, on the basis of current detected by the current sensor, the control unit controls switching elements so as to perform zero voltage switching at the time of turning-on, at a frequency at which a load including the resonant coil and the resonant capacitor becomes capacitive, and performs power regeneration of energy stored in a snubber capacitor to a DC voltage source.

Resonant inverter

A tablet printing device includes a first conveying disk that conveys a tablet while sucking and supporting a side surface of the tablet and an inkjet head capable of applying print processing to the front and back surfaces of the tablet conveyed by the conveying disk. The tablet is conveyed while being supported by a second conveying disk at its front and back surfaces and subjected to inspection of the side surface by a side surface inspection device. The tablet is transferred from the second conveying disk to the first conveying disk at a tablet delivery part and then supported by a suction hole formed in an end surface of the first conveying disk with the front and back surfaces fully exposed. The front and back surfaces are subjected to print processing ead, followed by print inspection, and only a non-defective tablet is discharged through a non-defective tablet discharge part.

Tablet printing device

A power conversion device including: a reactor formed such that a DC winding and a plurality of coupled windings are wound around one magnetic body, one end of the DC winding is connected to a voltage source, one end of each of the plurality of coupled windings is connected to another end of the DC winding, another end of each of the plurality of coupled windings is connected to each intermediate connection point between a plurality of upper and lower arms composed of switching elements, and a control device for controlling the switching elements, wherein switching of the upper arms or the lower arms is controlled in accordance with a magnitude of a duty of the switching operation and a magnitude relationship between DC current ripple and AC current ripple composing current ripple in the coupled windings.

A transformer is composed of three or more windings magnetically coupled. An AC/DC converter () for converting AC power of an AC power supply (), a capacitor (), and a switching circuit () are connected to one winding (), and a switching circuit () or () for power conversion of a DC power supply is connected to at least one of the other windings. Voltage of the capacitor () or the AC power supply () is detected. On the basis of the detected value thereof, the operation state of each switching circuit (), (), () is determined by an operation state determination circuit (). On the basis of a result of the determination, the power supply is switched among the AC power supply () and the DC power supplies () and () by an output switch circuit ().

Power conversion device which detects power shortage and switches to a power supply that is capable of supplying power

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Tokyo, Japan

Satoshi Murakami