Denso Corporation

Denso Corpora Tion

Kazuma Fukushima

Yuu Yamahira

Tetsuya Matsuoka

Hiroshi Shimizu

Mitsunori Kimura

Kengo Mochiki

Yasuyuki Ohkouchi

Ryota Tanabe

Tomohisa Sano

Noriyuki Kakimoto

Kosuke Kamiya

Masakiyo Sumitomo

Mamoru Kuwahara

Akifumi Araragi

Yuta Hashimoto

Taijiro Momose

Tomoya Miura

Disclosed is a cooling system for cooling an electric drive system. The electric drive system includes a motor and an inverter configured to drive the motor. The cooling system includes a first cooler, a second cooler, a circulating flow passage and a pump. The first cooler is configured to cool the motor by heat exchange using a coolant flowing through the first cooler. The second cooler is configured to cool the inverter by heat exchange using the coolant flowing through the second cooler. The circulating flow passage passes through both the first and second coolers, and the coolant circulates in the circulating flow passage. The pump is arranged in the circulating flow passage to pump the coolant.

Cooling system

A power module is applied to an electric power conversion device in which multiple upper-lower arm circuits are connected to an electric power line in parallel. The power module includes the multiple upper-lower arm circuits; a capacitor connected to each of the multiple upper-lower arm circuits in parallel; an upper wiring that connects an upper arm and a positive electrode terminal of the capacitor; a lower wiring that connects a lower arm and a negative electrode of the capacitor; an upper electric power wiring that is an electric power wiring connected to the electric power line and connects a high potential line of the electric power line and the upper wiring; and a lower electric power wiring that is an electric power wiring connected to the electric power line and connects a lower potential line of the electric power line and the lower wiring.

Power module and electric power conversion device

A power converter includes: at least one pair of first and second semiconductor devices including multiple first and second semiconductor chips, having first and second switching elements providing upper and lower arms, and multiple first and second main terminals having at least one of multiple first and second high potential terminals and multiple first and second low potential terminals; and a bridging member providing an upper and lower coupling portion, together with the first low and second high potential terminals. The first and second semiconductor chips are arranged in line symmetry with respect to first and second axes and in line symmetry with the second axis as a symmetry axis to differentiate the arrangement of the second low potential terminal with respect to the second high potential terminal from the arrangement of the first low potential terminal with respect to the first high potential terminal.

Power converter with an upper arm and a lower arm and at least first and second semiconductor devices connected by a bridging member

A power conversion apparatus has a positive electrode bus bar and a negative electrode bus bar. The power conversion apparatus has a first semiconductor module incorporating an upper-arm switching element and including a positive electrode terminal and a second semiconductor module incorporating a lower-arm switching element and including a negative electrode terminal. The first semiconductor module and the second semiconductor module are placed such that the positive electrode terminal and the negative electrode terminal face each other in a direction orthogonal to a protruding direction. The positive electrode bus bar and the negative electrode bus bar respectively have coexisting parts placed together between the positive electrode terminal and the negative electrode terminal as seen in the protruding direction of power terminals. The coexisting parts are at least partially placed in a space between the positive electrode terminal and the negative electrode terminal.

Power conversion apparatus

A power conversion device provided with a switching circuit unit including a plurality of upper-arm switching elements connected to positive electrode wiring and a plurality of lower-arm switching elements connected to negative electrode wiring. The power conversion device includes a first semiconductor module incorporating a plurality of the upper-arm switching elements connected together in parallel, a second semiconductor module incorporating a plurality of the lower-arm switching elements connected together in parallel, and a third semiconductor module incorporating the upper-arm switching elements connected together in series and the lower-arm switching elements connected together in series.

Power conversion device including a plurality of semiconductor modules

In a power conversion device, each of semiconductor modules of a layered body includes a body portion incorporating a plurality of switching elements and a plurality of power terminals protruding therefrom. The semiconductor modules include upper-arm switching elements and lower-arm switching element that are alternately layered in a layering direction of the layered body. A capacitor is disposed on one side of the layered body and a current sensor is disposed on an opposite side of the layered body, in an orthogonal direction orthogonal to both a protruding direction of the power terminals and the layering direction. Each of the semiconductor modules includes, as the power terminals, two collector terminals connected to a collector electrode of the switching element and one emitter terminal connected to an emitter electrode of the switching element, and the emitter terminal is disposed between the two collector terminals in the orthogonal direction.

Power conversion device

In a power converter, a control circuit has a speed adjustment resistor that limits a control current to adjust a switching speed of each of first and second switching elements. The speed adjustment resistor has a resistance that varies depending on a voltage at the control electrode of each of the first and second switching elements. A feedback route connects between the control electrode of the first switching element and the control electrode of the second switching element. The feedback route has a resistance that is set to be lower than a value of the resistance of the speed adjustment resistor during a predetermined Miller period of each of the first and second switching elements.

Power converter with switching elements, control circuit having speed adjustment resistor, and feedback route

A plurality of semiconductor elements and a control circuit unit are provided. The plurality of semiconductor elements which are connected in parallel are configured to perform switching at the same time. The control circuit unit includes a drive circuit connected to the plurality of semiconductor elements which perform operation at the same time, control wirings and reference wirings. The control wirings connect control electrodes of the semiconductor elements to the drive circuit. The reference wirings connect reference electrodes of the semiconductor elements to the drive circuit. A parasitic inductance in the reference wiring is made smaller than a parasitic inductance in the control wiring.

A power conversion apparatus performs power conversion. The power conversion apparatus includes a semiconductor module and a cooler. The semiconductor module includes an insulated-gate bipolar transistor, a metal-oxide-semiconductor field-effect transistor, and a lead frame. The insulated-gate bipolar transistor and the metal-oxide-semiconductor field-effect transistor are connected in parallel to each other and provided on the same lead frame. The cooler has a coolant flow passage. The coolant flow passage extends such that the coolant flow passage and the lead frame of the semiconductor module are opposed to each other. The semiconductor module is configured such that the metal-oxide-semiconductor field-effect transistor is not disposed further downstream than the insulated-gate bipolar transistor in a flow direction of a coolant in the coolant flow passage of the cooler.

A power conversion apparatus includes a semiconductor module including a semiconductor device and a control circuit unit controlling the semiconductor module. The semiconductor module has main and subsidiary semiconductor devices connected in parallel. The control circuit unit performs control such that the subsidiary semiconductor device is turned on after the main semiconductor device is turned on, and the main semiconductor device is turned off after the subsidiary semiconductor device is turned off. The control circuit unit performs control such that, one of the turn-on and turn-off switching timings has a switching speed faster than that of the other of the switching timings. The semiconductor module is configured such that, at a high-speed switching timing, an induction current directed to turn off the subsidiary semiconductor device is generated in a control terminal of the subsidiary semiconductor device depending on temporal change of a main current flowing to the main semiconductor device.

Parallely connected first and second switches respectively have first and second on resistances. The second on resistance is higher than the first on resistance in a lower range of current, and lower than the first on resistance in a higher range of current. A current obtaining unit obtains a current parameter indicative of an input current flowing through both the first and second switches. A low-current control unit controls, based on the obtained current parameter, switching operations of the first and second switches to correspondingly increase the number of times of turn-on of the first switch relative to the number of times of turn-on of the second switch, and prevent simultaneous turn-on of the first and second switches while a value of the input current is located within a predetermined low-level current region, the low-level current region being lower than the threshold current.

Drive control apparatus

A semiconductor module includes an IGBT and a MOSFET. The IGBT is made of a silicon semiconductor. The MOSFET is made of a wide-bandgap semiconductor having a wider bandgap than the silicon semiconductor. The IGBT and the MOSFET are connected in parallel to each other to form a semiconductor element pair. The IGBT has a greater surface area than the MOSFET. The semiconductor module is configured to operate in a region that includes a low-current region and a high-current region. Electric current flowing through the semiconductor element pair is higher in the high-current region than in the low-current region. In the low-current region, the on-resistance of the MOSFET is lower than the on-resistance of the IGBT. In contrast, in the high-current region, the on-resistance of the IGBT is lower than the on-resistance of the MOSFET.

Semiconductor module and electric power conversion apparatus

In a driving apparatus for switches connected in parallel to each other, drivers respectively turn on or off the switches. A temperature obtainer obtains a value of a temperature parameter correlating with a temperature of at least one of the first and second switches. A selector selects at least one of the switches as at least one drive target switch. A driver causes at least one of the drivers to turn on the at least one drive target switch during an on duration and thereafter turn off the at least one drive target switch in each target switching cycle. The selector adjusts the number of the selected at least one drive target switch based on the value of the temperature parameter.

Driving apparatus for switches

A power conversion apparatus includes a first semiconductor element pair that includes a MOSFET made of wide bandgap semiconductor material and a wide bandgap diode made of wide bandgap semiconductor material which is reverse parallel-connected to the MOSFET, a second semiconductor element pair that includes an IGBT made of silicon semiconductor material and a silicon diode made of silicon semiconductor material which is reverse parallel-connected to the IGBT, and a control circuit section for controlling switching operation of the MOSFET and the IGBT. The first and second semiconductor element pairs are connected in series to each other.

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Kariya, Japan

Kazuma Fukushima