Hitachi, Ltd.

The Kansai Electric Power Co., Inc.

Hitachi Mitsubishi Hydro Corporation

Hitachi Information & Control Solutions, Ltd.

Hitachi Engineering Services Co., Ltd.

Sumco Corporation

Tamura Corporation

Hitachi Industry & Control Solutions, Ltd.

Hitachi Industrial Products, Ltd.

East Japan Railway Company

The Kansai Elect. Power Co.

Akira Bando

Hiroto Nakagawa

Masaya Ichinose

Yasuhiro Kiyofuji

Masakazu Ishikawa

Shin Kokura

Naoya Mashiko

Masamitsu Kobayashi

Eiji Haraguchi

Satoru Funaki

Osamu Nagura

Akihiro Onozuka

Kenichi Ono

Takashi Hotta

Kotaro Shimamura

Takao Kuwabara

Wataru Sasaki

Shigeta Ueda

Masahiro Shiraishi

Tomomichi Ito

Yoshitaka Takahashi

Hiromichi Endoh

Yusaku Otsuka

Yasuteru Oono

Takashi Umehara

Yu Iwasaki

Keiji Saito

Junichi Shiozaki

Takahiko Kikui

Hisao Nagayama

Eiji Kobayashi

Toru Yoshihara

Yuichiro Morita

Kazuhiro Imaie

Shigenori Inoue

Mitsuyasu Kido

Tadao Kawai

Chikara Tanaka

Eizo Kita

Yasuhiro Imazu

Kenta Watanabe

Hiroshi Sugisaka

Takeshi Takehara

Shigehiro Kayukawa

Hiroshi Kashiwazaki

Takayoshi Yamamoto

Osamu Sakuchi

Yasuteru Ohno

Keiichi Mitsuhashi

Ryuichi Murakawa

Hideyuki Yoshikawa

Tsutomu Yamada

Yasuhiro Nakatsuka

Hirokazu Suzuki

Shuji Katoh

Koji Sakamoto

Hiromitsu Sakai

Seiichi Nakamura

Yusuke Seki

Masahiko Honda

Hideki Nishihata

Naomi Sato

Kazuo Mera

Nobuo Tsumaki

Toshiki Shimizu

Tomoji Watanabe

Hironari Kawazoe

Hideaki Masuko

Akira Kikuchi

Hashime Nagai

Yasuyuki Furuta

Riyuusuke Kasamatsu

Jun Narushima

Yuuichiro Morita

Ichiro Hitomi

Haruo Nohara

Akihiro Sakayori

Shigeaki Hayashi

Hikaru Meguro

Yoshio Eguchi

Akihiro Nakano

Shoichi Ozawa

Ikuro Miyashita

Yasuaki Nakayama

Yoji Tanaka

Takashi Oyake

Hiroyasu Satou

Akira Momiyama

Toshihiko Usui

Masaki Uchita

Junichi Shiozaki, Deceased

Toshio Taguchi

Rikiya Inoue

Junko Shiozaki

Takao Kuwahara

Masahiro Minato

Yosuke Nakaide

Keiichi Yamashita

Kazunori Tsubuku

Tsuneo Hayashi

There is provided an adjustable speed generator motor system with full power converter (FPC system) in which two 3-level converters are connected back-to-back on the DC side, and by providing a mode in which a fly-wheeling diode is forced to conduct a current independently for three phases according to the current polarity and a mode in which the fly-wheeling diode is forced to conduct a current independently for three phases according to magnitude relation of the absolute value of a 3-phase AC current and the current polarity of each phase the FPC system is capable of continuing stable operation.

Adjustable speed generator motor system with full power converter

A modular multilevel power converter includes: a capacitor voltage adjuster that calculates an active current component command to make an average voltage of capacitors match a command value; an active power detector that receives an AC current signal and an AC voltage signal and calculates an active power; an active power adjuster that calculates a DC current command value to make the active power match a command value; a first active power command suppressor that suppresses an absolute value of an active power command value; and a second active power command suppressor that adjusts an absolute value of an active power command value.

Modular multilevel power converter and variable speed generator-motor

An MMC converter includes three units of two-terminal arms on a P-terminal side, and three units of two-terminal arms on an N-terminal side. An inductive element between the arms on the P-terminal side and the arms on the N-terminal side includes a reactor provided with a UP coil and a UN coil concentrically wound around an iron-core leg, a reactor provided with a VP coil and a VN coil concentrically wound around an iron-core leg, and a reactor provided with a WP coil and a WN coil concentrically wound around an iron-core leg. Each of the coils is wound around in a direction such that the iron-core legs are excited by a flow-through current from the N terminal to the P terminal.

Modular multilevel converter and modular multilevel converter system

A secondary magnetic excitation generator-motor device that inputs a first ignition pulse command to a three-level NPC power converter such that a detected excitation current value corresponds with an excitation current command value, the secondary magnetic excitation generator-motor device having a function of identifying a first phase, a second phase, or a third phase in descending order of a current absolute value, wherein a pulse switch to output an ignition pulse command to the three-level NPC power converter switches the ignition pulse command to the second ignition pulse command when a current absolute value exceeds a set overcurrent level 1, and switches the ignition pulse command to the first ignition pulse command when current absolute values for three phases are all equal to or smaller than a set overcurrent level 2.

Secondary magnetic excitation generator-motor device

In a variable speed generator/motor device including a variable frequency power converter, a direct current voltage device including a voltage type self-excited converter, an automatic voltage adjuster, and a converter current adjuster that controls unit converters, a first three-phase branch circuit is provided between the direct current voltage device and an alternating current system; a second three-phase branch circuit is provided between the variable frequency power converter and a three-phase alternating current synchronous machine; a first load switch is provided between the first three-phase branch circuit and the second three-phase branch circuit; a measurement current transformer is provided between the three-phase alternating current synchronous machine and the second three-phase branch circuit; when switching from a converter mode in which the variable frequency power converter drives the three-phase alternating current synchronous machine to generate power to a bypass mode, the first load switch is closed to stop a gate command to the unit converters; and when switching from the bypass mode to the converter mode, a current command value of the converter current adjuster is calculated from a current value of the measurement current transformer, the gate command to the unit converters is started, and the first load switch is opened.

Variable speed generator/motor device

In a variable speed generator-motor apparatus, a power converter includes six two-terminal arms each formed by serially connecting k unit converters that can output arbitrary voltage, an AC rotating electric machine includes an armature winding with 60-degree phase zone formed from a double layer coil, the armature winding being divided into first and second pole sides to form double star connection by binding neutral points and to be drawn out as two sets of three-phase terminals; three-phase terminals on the first pole side are connected to first terminals of three arms, and second terminals of the three arms are star-connected to a first terminal of a DC power supply; three-phase terminals on the second pole side are connected to second terminals of remaining three arms, and first terminals of the three arms are star-connected to a second terminal of the DC power supply.

Variable speed generator-motor apparatus and variable speed generator-motor system

Feeder sections to be a target of interchange are to be expanded in order to improve the effect of power interchange between feeders. A control device for railway power conditioner is connected to a first feeder connected to a load side of a transformer in a first railway substation including a transformer receiving power from a power grid, and a second feeder connected to a load side of a transformer in a second railway substation including a transformer receiving power from a power grid, and decides an amount of power interchanged between the first and second feeders. The control device decides the amount of power interchanged between the first and second feeders, using the received power in the first railway substation and power on the first feeder, and the received power in the second railway substation and power on the second feeder.

Control device for railway power conditioner and control system for railway power conditioner

A switching element of a power converter generates a low voltage, using a current flowing in the power converter, and supplies a power to drive itself. A switching element of a power converter for conversion from direct current into alternate current or from alternate current into direct current includes: a terminal and a terminal which are used in building the switching element itself in the power converter; a capacitor, a high-side controllable switch and a low-side controllable switch enabling outputting the voltage of the capacitor, the voltage being output between the terminal and the terminal, and a self-supply power source for supplying a power to drive the bi-directional chopper switching element itself, using a current flowing in the capacitor.

Switching element, power converter, direct current transmission system, current control device, method of controlling power converter, and method of controlling current in voltage source converter

The present invention provides a duplexed operation processor control system that includes operation processors, an I/O device, and at least one communication path that couples the operation processors to the I/O device, and at least one communication path that couples the operation processors with each other. The duplexed operation processor control system switches over either of the operation processors to be a primary operation processor that executes a control operation for a control target, and the other to be a secondary operation processor that is in a stand-by state, and the secondary operation processor snoops control data synchronously when the primary operation processor acquires the control data from the control target.

Duplexed operation processor control system, and duplexed operation processor control method

A control apparatus for use with a voltage source converter includes legs, each of which is configured by a plurality of converter modules each having a capacitor. Each of the legs has a first terminal on a positive side and a second terminal on a negative side. The control apparatus is configured to create command pulses for operating the converter modules. The command pulses have a frequency that is a non-integer multiple of a frequency of a system voltage. The non-integer multiple may be, for example, 3.5.

Multilevel voltage source converter and method for balancing capacitors

The excitation overcurrent detection unit for the doubly-fed electric machine is provided with a function to determine an excitation current magnitude relationship among three phases. The firing pulse is held to on-state or off-state to cause the largest-current phase and the second-largest-current phase to charge the DC capacitor by the operation of diodes. The conduction ratio of the third-largest-current phase or minimum current phase is controlled according to the detected current value to protect against a possible short-circuit across the DC capacitor. When the voltage of the DC capacitor exceeds a preset value, the voltage is suppressed by operating active or passive power devices.

Doubly-fed generator and doubly-fed electric machine

A commanded negative-sequence current is added to a commanded current so as to suppress double-frequency pulsation on the DC side. The commanded negative-sequence current is found from three values (i.e., the detected value of positive-sequence voltage vector on the power-supply side, the detected value of negative-sequence voltage vector, and a commanded positive-sequence current). Thus, the pulsations which occur on the DC side of a semiconductor power converter and which have a frequency double the power-supply frequency are suppressed even when the AC power supply is at fault while assuring stability of the current control system, thus permitting stable and continuous operation.

DC/AC power converter with DC side double frequency pulsation suppression caused by AC side faults

A control apparatus for an input-output device includes a hardware part and a software part, in which a controller in the hardware part carries out a control operation in accordance with a signal from the input-output device, outputs a result of the control operation to a process, and has a timer unit to be excited at a constant period; and the software part has an information process part, a control process part, and an interrupt control unit to switch over the information process part and control process part one another, in which the interrupt control unit suspends an execution of the information process part to execute the control process part in priority and resume the information process part by switching over to the information process part from the control process part, when the execution of the control process part is terminated.

Control apparatus for process input-output device

A receiving device including: a receiver receiving two frames, each including substantially same data attached thereto with a data error detection code, a frame error detection code, and safety flag information indicating a safety function or not, respectively; a first detector connected to the receiver for performing error detection of the frames by use of the frame error detection code, respectively; a second detector connected to the receiver for performing error detection of the data by use of the data error detection code, respectively; and a Direct Memory Access Controller (DMAC) connected to the first and second detectors for outputting one among the data included in the two frames under a condition of the safety function in the two frames when no error is detected in the frame and data error detections.

Sending device, receiving device, communication control device, communication system, and communication control method

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Hitachi, Japan

Akira Bando