Hitachi, Ltd.

Sony Corporation

Kazutoshi Ogawa

Hiroshi Kageyama

Takeshi Tanaka

Katsumi Ishikawa

Kiyoshi Nakata

Toru Masuda

Masahiro Nagasu

Ayumu Hatanaka

Hideki Ayano

Tsutomu Kominami

Mami Kunihiro

Takeo Takagi

Tomomi Kanazawa

Shuichi Terakado

Takeshi Shinomiya

Masaomi Konishide

Kuniaki Otsuka

Naoki Kunihiro

Hiroyuki Shirata

Shigeo Isayama

This three-phase AC motor drive device is provided with: a load; an inverter devicefor driving the load; an MCOK_A_connected between the inverter deviceand the load and electrically connecting or disconnecting the inverter deviceto or from the load; a voltage detectorhaving terminals respectively connected to the circuits of at least two phases to detect the voltages between the three phases; and a current detectorfor detecting the currents of the three phases. In the connection from the inverter deviceto the load, the inverter device, the MCOK_A_, the voltage detector, the current detector, and the load are aligned in this order.

Three-phase AC motor drive device, rail vehicle equipped with same, and three-phase AC motor drive method

A power semiconductor apparatus which is provided with a first power semiconductor device using Si as a base substance and a second power semiconductor device using a semiconductor having an energy bandgap wider than the energy bandgap of Si as a base substance, and includes a first insulated metal substrate on which the first power semiconductor device is mounted, a first heat dissipation metal base on which the first insulated metal substrate is mounted, a second insulated metal substrate on which the second power semiconductor device is mounted, and a second heat dissipation metal base on which the second insulated metal substrate is mounted.

Power semiconductor with a Si chip and a wideband chip having matched loss and area ratios

Temperature rise in semiconductor switching element that is part of a power conversion device is estimated to assess the degradation and remaining lifetime of the switching element. This is accomplished with a heat generation amount calculation unit in a calculation processor, where current command values Id* and Iq* and voltage command values vu*, vv* and vw* are used to calculate a chip loss. Current values iu*, iv* and iw* of all output phases are estimated from the current command values. The ON/OFF loss of the chip is represented by a function of an estimated value for a current flowing in each output phase, and the loss can be derived by integration with a PWM carrier frequency f. With respect to a conduction loss, a conduction time is integrated with the estimated current value and a saturation voltage, which is a function of the estimated current value.

Power conversion device and temperature rise calculation method thereof

The present invention provides a power converter which, while ensuring safety, implements control for the flow of a constant current in a specified switching element, more accurately determines the lifetime of a switching element, and reduces the number of temperature detectors. The power converter is provided with a mechanism which causes a brake device to operate or which confirms that a brake mechanism is operating. The power converter supplies current to the d-axis and the q-axis of a rotational coordinate system, within the range of the braking torque of the brake mechanism, and passes the desired current to the desired element. Furthermore, temperature detectors are attached only in chips in sections where a crack readily develops in the upper solder layer or peeling is readily generated in the wire bonding, and in chips where a crack readily develops in the lower solder layer.

Power converter

In order to reduce the average power of the ringing noise, the present invention provides a power converter comprising: an arm circuit including a high-voltage side switching device to which a first diode is connected in parallel and a low-voltage side switching device to which a second diode is connected in parallel; and a main power supply connected to a series circuit of the high-voltage side switching device and the low-voltage side switching device, wherein a connecting point between the high-voltage side switching device and the low-voltage side switching device is connected to a load, and a resonant frequency calculated from inductances of wirings of a closed circuit including the first diode, the second diode, and the main power supply and a capacitance across the first diode is different form that calculated from the inductances of the wirings and a capacitance across the second diode.

Power converter and motor driving device using the same

The invention provides a switching circuit of a power semiconductor device having connected in parallel SiC diodes with a small recovery current, capable of significantly reducing turn-on loss and recovery loss without increasing the noise in the MHz band, and contributing to reducing the loss and noise of inverters. The present invention provides a switching circuit and an inverter circuit of a power semiconductor device comprising a module combining Si-IGBT and SiC diodes, wherein an on-gate resistance is set smaller than an off-gate resistance.

Drive circuit of semiconductor device

Power semiconductor apparatus having a silicon power semiconductor device and a wide gap semiconductor device

The threshold value for a normally-off junction FET is a low value. Accordingly, in a semiconductor driver circuit using the normally-off junction FET, there have existed such problems as high-accuracy voltage control, high-speed charging into an input capacitor, and misoperations. A semiconductor driver circuit which is the most suitable for the normally-off junction FET is proposed by applying the high-accuracy gate-voltage generation scheme based on a Zener diode, a reduction in the turn-on loss based on a speed-up capacitor, the connection of an inter-gate-source capacitor, and a misoperation-preventing circuit based on the source-terminal optimum implementation scheme.

Drive circuit for switching device

The invention provides a switching circuit and a power converter having a built-in power source for a conduction control terminal even if they have a single-arm structure. In the switching circuit having a switching device and a conduction control terminal power source capacitor, a negative terminal of the capacitor is connected to a reference voltage terminal of a main power source and to the gate terminal selectively through a half-bridge circuit and a positive terminal of the capacitor is selectively connected to a positive terminal of the main power source and to a source terminal of the switching device through a half-bridge circuit. The capacitor is charged when the positive terminal is connected to the main power source and discharges when the negative terminal is connected to the gate terminal and the positive terminal is connected to the source terminal and applies voltage to the gate terminal of the switching device.

Switching circuit and power converter

An automatic circuit adjusting system comprises a circuit adjusting tool assembly. The circuit adjusting tool assembly is movable to adjust different orientations of circuit elements. The circuit adjusting tool assembly has a plurality of adjusting tools. The circuit adjusting tool assembly is controlled in its movement and selection of adjusting tools by means of a microprocessor based controller. The controller is so programmed as to shift the circuit adjusting tool assembly to different orientations of circuit elements on a printed circuit board in order according to a preset order. The controller is also preset to schedule selection of the desired one of the adjusting tools corresponding to the position of the circuit adjusting tool assembly. According to the preferred construction, the circuit adjusting tool assembly comprises a single common driving motor for driving a plurality of the adjusting tools. Driving torque of the driving motor is distributed to the respective adjusting tools through a common power train that drives all of them at the same speed and magnitude. The adjusting tools in the circuit adjusting tool assembly are thrustingly movable in an axial direction to engage with their respective one of the cirucit elements to be adjusted. The adjusting tools are normally placed in an idling position and shifted to an active position to engage with the corresponding cirucit elements when selected by the controller.

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Hitachi, Japan

Kazutoshi Ogawa