Hitachi, Ltd.

Other

Hitchi, Ltd.

Shin Kimura

Mutsuhiro Mori

Hiroshi Fukui

Kiyoshi Nakata

Ryuichi Saito

Masahiro Nagasu

Tsutomu Yatsuo

Akira Horie

Yoshihiko Koike

Yoshio Terasawa

Syuuji Saitoo

Shigeki Sekine

Hideki Miyazaki

Kenichi Onda

Yasuo Matsuda

Takahiro Nagano

Norikazu Tokunaga

Junichi Sakano

Takayuki Iwasaki

Hisao Amano

Saburo Oikawa

Hideo Kobayashi

Satoshi Shimada

Katsunori Suzuki

Kazuji Yamada

Kazuhiro Suzuki

Satoshi Ibori

Naoki Sakurai

Nobuyoshi Mutoh

Hidekatsu Onose

Naohiro Momma

Jin Onuki

Hirokazu Inoue

Yutaka Sato

Masayoshi Sato

Tomoyuki Tanaka

Isao Kobayashi

Yasumichi Yasuda

Shinji Yamada

Yasutoshi Kurihara

Mutsuhiro Terunuma

Satoru Inarida

Shuji Musha

Toshiki Kurosu

Yukio Kamita

Shuuji Musha

Yukimasa Sato

A railway vehicle operation-control system includes at least one central processing unit being connected to a plurality of devices, which are connected in parallel, via information communication means, the plurality of the devices having at least one operational state-monitoring function which transmits information on operational states of each device to the central processing unit; wherein a total controlled-variable necessary for the system is attained by allocating the total control variable to each device based on operational states determined from results of monitoring performed by the operational state-monitoring function, and a performance margin which is defined as a difference between a permissible power-output value and a current power-output value for each device while monitoring and reflecting the performance margin of each device.

Railway vehicle operation-control system and a railway vehicle using the operation control system

A semiconductor circuit or a semiconductor device has the current-voltage characteristic that, in a blocking-state of the semiconductor circuit or the semiconductor device, a current gently flows for values of a voltage equal to or greater than a first voltage value but equal to or smaller than a second voltage value, whereas a current abruptly flows for values of a voltage greater than the second voltage value. Due to the current-voltage characteristic, energy accumulated in an inductance provided within the circuit is consumed by a differential resistance of the semiconductor circuit or a semiconductor, thereby preventing the occurrence of the electromagnetic noise and an excessively large voltage.

Semiconductor circuit preventing electromagnetic noise

A semiconductor module has a plurality of power semiconductor devices mounted on a substrate, and a metal foil for wiring is mounted on the substrate so that an asymmetric unit arrangement of the semiconductor devices is formed. In the device, all of the units are arranged in the same direction on the substrate, and all of the units are electrically connected with electrode terminal feet, and the electrode terminal feet are electrically connected with linkage terminal foot. The electrode terminal feet are disposed with a certain interval.

Semiconductor module

A wide bandgap semiconductor single crystal is applied as a semiconductor substrate material of a semiconductor surge absorber, and a surge absorption operation starting voltage is set by a punchthrough of a pn junction, to obtain a semiconductor surge absorber with a repetitive operation and a high surge endurance.

Semiconductor surge absorber, electrical-electronic apparatus, and power module using the same

In order to detect a current with high accuracy in an electric power converting system, an inductor is connected to a main terminal of a switching element in series, and a voltage generated in both ends of the inductor during switching period is integrated using an integrating circuit to detect the current.

Electric power converting system with integrator providing output indicative of current

A gate drive circuit of a voltage drive switching element, which is characterized by control of di/dt and dv/dt when an IGBT is switched by controlling increases in the switching time and loss of the IGBT, includes a drive means for amplifying a signal for controlling the switching operation of a voltage drive switching device including the IGBT, a means for detecting the gate voltage of the IGBT, a voltage decrease (increase) means for slowly decreasing (increasing) the output voltage when the drive means is turned on (off) in the course of time, and a voltage increase (decrease) means for slowly increasing (decreasing) the output voltage. By switching from the voltage decrease (increase) means to the voltage increase (decrease) means according to the detected value of the gate voltage of the IGBT, di/dt and dv/dt are controlled when the IGBT is turned on (off).

Gate drive circuit of voltage drive switching element

A semiconductor circuit or a semiconductor device has the current-voltage characteristic that, in a blocking-state of the semiconductor circuit or the semiconductor device, a current gently flows for values of a voltage equal to or greater than a first voltage value but equal to or smaller than a second voltage, whereas a current abruptly flows for values of a voltage greater than the second voltage value. Due to the current-voltage characteristic, energy accumulated in an inductance provided within the circuit is consumed by a differential resistance of the semiconductor circuit or a semiconductor, thereby prevent the occurrence of the electromagnetic noise and the excessively large voltage.

Semiconductor circuit and semiconductor device for use in equipment such as a power converting apparatus

A power converting apparatus comprising a group of semiconductor switches and DC terminals electrically connected to the group of semiconductor switches, in which a clamping circuit is connected to the semiconductor switches or the DC terminals. Otherwise, a diode having a wide band gap is connected in parallel with a snubber diode or a snubber capacitor of a snubber circuit connected in parallel with the semiconductor switches. With such arrangement, an overvoltage or oscillating voltage impressed on the semiconductor switches is suppressed.

Power converter with clamping circuit

An inverter device includes plural modules, each module being formed by a series circuit having a parallel circuit of a switching device and a first diode, and a parallel circuit of a second switching device and a second diode, allowing a reduced size, high reliability, high frequency switching and low noise. Each of the semiconductor modules includes a plurality of switching device chips and at least one diode chip formed on a metal substrate. Electrode plates are provided in locations of the module adjacent to the switching device chips and the diode chips to facilitate connection of the electrodes of the respective chips to one another and to the outside of the module.

Semiconductor module including switching device chips and diode chips

An inverter device includes plural modules, each module being formed by a series circuit having a parallel circuit of a first switching device and a first diode, and a parallel circuit of a second switching device and a second diode, allowing a reduced size, high reliability, high frequency switching and low noise.

Semiconductor module for a power conversion device

An inverter device includes plural modules, each module being formed by a series circuit having a parallel circuit of a first switching device and a first diode, and a parallel circuit of a second switching device and a second diode, allowing a reduced size, high reliability, high frequency switching and low noise. Each module forms one arm portion of the inverter. Lifetimes of the diodes and the switching devices are set in a manner to equalize losses in the inverter. Preferably, insulated gate bipolar transistors (IGBTs) formed by diffusion are used as the switching devices since the lifetimes of these devices can easily be adjusted to optimize design of the inverter.

Power conversion device and semiconductor module suitable for use in the

Neutral-point clamped inverter device using semiconductor modules

In a module using a high-speed switching element such as an IGBT for a high-speed inverter, a matching condition is established between the switching characteristic of the IGBT and the recovery characteristic of the diode to be connected thereto in an anti-parallel fashion. As a result, the oscillating voltage appearing in the inverter circuit is suppressed to prevent erroneous operation of the inverter system.

Parallel circuit module including a diode and an IGBT

An ON holding circuit is provided which outputs a signal which identifies an ON state of an insulated gate transistor to a gate voltage input circuit, and inhibits the gate voltage input circuit from being responsive to an input signal which identifies an OFF state of the insulated gate transistor when an overcurrent adjusting circuit operates continuously.

Drive circuit for an insulated gate transistor having overcurrent

A gate turn-off thyristor and a transistor are disclosed, each of which comprises: a semiconductor substrate including at least three semiconductor layers between a pair of principal surfaces, adjacent ones of the semiconductor layers being different in conductivity type from each other, a first one of the semiconductor layers being formed of at least one strip-shaped region with a constant width, a second one of the semiconductor layers being exposed to a first principal surface of the semiconductor substrate together with the strip-shaped region; a first main electrode kept in ohmic contact with the strip-shaped region at the first principal surface; a first control electrode kept in ohmic contact with the second semiconductor layer on one side of the strip-shaped region in the direction of the width thereof and connected directly to a control terminal; a second control electrode kept in ohmic contact with the second semiconductor layer on the other side of the strip-shaped region in the direction of the width thereof and connected to the control terminal through the first control electrode and the resistance of the second semiconductor layer between the first control electrode and the second control electrode; a second main electrode kept in ohmic contact with a second principal surface of the semiconductor substrate; and means provided in the semiconductor substrate for accelerating the spatial biasing of a conductive region to the other side of the strip-shaped region in the direction of the width thereof when a current flowing across the semiconductor substrate is cut off, thereby enlarging the area of safety operation.

Semiconductor device provided with electrically floating control

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Hitachi, Japan

Shin Kimura