Toyota Jidosha Kabushiki Kaisha

Kabushiki Kaisha Toyota Chuo Kenkyusho

Denso Corporation

Takahide Sugiyama

Kenichi Takagi

Jun Saito

Kenichiro Nagashita

Shuntaro Inoue

Masaki Okamura

Masanori Usui

Yusuke Yamashita

Sachiko Aoi

Satoru Machida

Yoshitaka Niimi

Koji Hotta

Sachiko Kawaji

Takaji Umeno

Masanori Ishigaki

Akitaka Soeno

Tatsuji Nagaoka

Shinya Iwasaki

Tomoyoshi Kushida

Masaki Koyama

Yasushi Ookura

Tadashi Misumi

Shinya Yamazaki

Hiroko Iguchi

Shuji Tomura

Jiro Nakano

Naoyoshi Takamatsu

Takahiro Hirano

Hiroyuki Kano

Shigeaki Goto

Akinori Seki

Masaru Sugai

Kazuyoshi Tomita

Jun Muto

Hiroshi Osada

Fumiki Tanahashi

Makoto Imai

Satoshi Hirose

Norimune Orimoto

Toyokazu Ohnishi

Masayasu Ishiko

Tomoyuki Shoji

Disclosed is a technique capable of reducing loss at the time of switching in a diode. A diode disclosed in the present specification includes a cathode electrode, a cathode region made of a first conductivity type semiconductor, a drift region made of a low concentration first conductivity type semiconductor, an anode region made of a second conductivity type semiconductor, an anode electrode made of metal, a barrier region formed between the drift region and the anode region and made of a first conductivity type semiconductor having a concentration higher than that of the drift region, and a pillar region formed so as to connect the barrier region to the anode electrode and made of a first conductivity type semiconductor having a concentration higher than that of the barrier region. The pillar region and the anode are connected through a Schottky junction.

Diode, semiconductor device, and MOSFET

A power supply circuit includes inductors, capacitors, and switching elements. Ports are electrically insulated from each other. Two switching elements are alternately switched, and two other switching elements are alternately switched. The inductors are wound such that a magnetic flux is generated in the same direction when a phase difference between the switchings of the switching elements is zero. Duties of the switchings of the switching elements are changed equally, and a phase difference between the switchings is changed.

Power supply circuit including converter and power supply system using the same

An electric power conversion circuit comprises U-phase and V-phase switching circuits, a transformer, and an &#x3b1;-phase switching circuit. A primary winding of a transformer is connected between the U-phase switching circuit and the V-phase switching circuit, and both ends of a secondary winding are connected to the &#x3b1;-phase switching circuit. The &#x3b1;-phase switching circuit comprises positive and negative terminals, a half bridge including and two switching devices, and a voltage divider circuit. The half bridge is provided between the positive terminal and the negative terminal, and a common connection point between the two switching devices is connected to one end of the secondary winding. A voltage divider output point of the voltage divider circuit is connected to the other end of the secondary winding.

Electric power conversion circuit

A power supply system includes first and second DC power supplies and a power converter having first to fifth semiconductor elements and first and second reactors. The first and fourth semiconductor elements are electrically connected between a first node and a second node, and a first power line, respectively. Second and third switching elements are electrically connected between the first node and the second node, and a second power line, respectively. A fifth switching element is electrically connected between the first node and the second node. The first reactor is electrically connected in series with the first DC power supply, between the first node and the second power line. The second reactor is electrically connected in series with the second DC power supply, between the first power line and the second node.

Power supply system having two DC power supplies

The present invention provides a power conversion circuit system in which a circulating current can be reduced by accurately detecting the circulating current, to thereby improve efficiency in power conversion. The power conversion circuit system includes a power conversion circuit composed of a primary conversion circuit having left and right arms and a secondary conversion circuit having left and right arms, and a control circuit for controlling switching of switching transistors in the primary and secondary conversion circuits. The control circuit detects the circulating current at at least one of timings lagged by &#x3c0;/2+&#x3c6;/2 from at least either a peak timing or a valley timing in a carrier counter where &#x3c6; represents a difference in phase between the primary and secondary conversion circuits, and performs feedback control for reducing the detected circulating current to zero.

Isolated DC-DC power conversion circuit system with circulating current reduction

An electric power conversion circuit system for reducing core loss in a transformer particularly during light loading and improving conversion efficiency during light loading comprising an electric power conversion circuit composed of a primary side conversion circuit having a left arm and a right arm and a secondary side conversion circuit having a left arm and a right arm, and a control circuit for controlling switching of switching transistors of the first side conversion circuit and the secondary side conversion circuit. When the output voltage is at a relatively light load, the control circuit controls to change the duty of the transmitting side among the primary side conversion circuit and the secondary side conversion circuit and controls to change the half-bridge phase differences of the left arm and the right arm of the primary side conversion circuit and the secondary side conversion circuit, respectively.

Electric power conversion circuit system

A magnetically coupled reactor includes a coupled core member, a first coil, and a second coil. The coupled core member includes a first core and a second core made of a magnetic material and disposed to face each other, a coil channel, and a sheet-like magnetic body by which a coupling portion between cores is put between the first core and the second core at an outer portion of the first and second cores. Each coil is wound around a leg through the coil channel in a lap winding manner such that the coils are overlapped on top of each other in the coil channel when seen in an axial direction. The sheet-like magnetic body extends from the coupling portion between coils into the coil channel and includes a portion arranged between coils located between the coils in the axial direction.

Magnetically coupled reactor and power converter

There is provided an electric power conversion circuit system having a primary side electric power conversion circuit, a secondary side electric power conversion circuit, and a control circuit. The control circuit sets at least one of a half-bridge phase difference between a lower-left-arm transistor and a lower-right-arm transistor of the primary side electric power conversion circuit and a half-bridge phase difference of the secondary side electric power conversion circuit based on OFF periods of the primary side and secondary side electric power conversion circuits, dead-times of the primary side and secondary side electric power conversion circuits, and an amount of change of a power supply voltage so that a current in a non-transmission period of electric power is zero between the primary side and secondary side electric power conversion circuits.

A cooling type switching element module includes an outer conductor pipe, an inner conductor pipe that transmits electric power in conjunction with the outer conductor pipe, and first and second switching elements. The first switching elements are provided on outer surfaces of the outer conductor pipe, and the second switching elements are provided on outer surfaces of a projecting portion of the inner conductor pipe. A coolant flows within the inner conductor pipe, and outside the outer conductor pipe. The first and second switching elements are cooled from both sides by the coolant flowing within the inner conductor pipe, and by the coolant flowing outside the outer conductor pipe. By employing the above-described structure, it is possible to provide a switching element module having a cooling function, in which improved cooling performance, improved electrical performance, and downsizing are achieved.

Cooling-type switching element module

There is known a semiconductor device in which an IGBT structure is provided in an IGBT area and a diode structure is provided in a diode area, the IGBT area and the diode area are both located within a same substrate, and the IGBT area is adjacent to the diode area. In this type of semiconductor device, a phenomenon that carriers accumulated within the IGBT area flow into the diode area when the IGBT structure is turned off. In order to prevent this phenomenon, a region of shortening lifetime of carriers is provided at least in a sub-area that is within said IGBT area and adjacent to said diode area. In the sub-area, emitter of IGBT structure is omitted.

Semiconductor device having both IGBT area and diode area

A semiconductor device comprises a semiconductor substrate, a first electrode formed on a first main surface of the semiconductor substrate, and a second electrode formed on a second main surface of the semiconductor substrate. The semiconductor substrate includes a first region in which a density of oxygen-vacancy defects is greater than a density of vacancy cluster defects, and a second region in which the density of vacancy cluster defects is greater than the density of oxygen-vacancy defects.

Reverse recovery using oxygen-vacancy defects

A diode region and an IGBT region are formed in a semiconductor layer of a semiconductor device. A lifetime controlled region is formed in the semiconductor layer. In a plan view, the lifetime controlled region has a first lifetime controlled region located in the diode region and a second lifetime controlled region located in a part of the IGBT region. The second lifetime controlled region extends from a boundary of the diode region and the IGBT region toward the IGBT region. In the plan view, a tip of the second lifetime controlled region is located in a forming area of the body region in the IGBT region.

Semiconductor device

In a semiconductor device, an IGBT cell includes a trench passing through a base layer of a semiconductor substrate to a drift layer of the semiconductor substrate, a gate insulating film on an inner surface of the trench, a gate electrode on the gate insulating film, a first conductivity-type emitter region in a surface portion of the base layer, and a second conductivity-type first contact region in the surface portion of the base layer. The IGBT cell further includes a first conductivity-type floating layer disposed within the base layer to separate the base layer into a first portion including the emitter region and the first contact region and a second portion adjacent to the drift layer, and an interlayer insulating film disposed to cover an end of the gate electrode. A diode cell includes a second conductivity-type second contact region in the surface portion of the base layer.

Growing community of inventors

Nagakute, Japan

Takahide Sugiyama