Hitachi, Ltd.

Hitachi Construction Machinery Co., Ltd.

Other

Hitachi Industrial Equipment Systems Co., Ltd.

Fuji Heavy Industries Ltd.

Hitachi Home and Life Solutions, Inc.

Motoo Futami

Masaya Ichinose

Shinya Oohara

Akira Kikuchi

Mitsugu Matsutake

Hiromitsu Sakai

Kazuhiro Imaie

Kouichi Miyazaki

Kenji Takeda

Hironari Kawazoe

Kazumasa Ide

Masahiro Komachiya

Tsunehiro Endo

Shin Yamauchi

Mamoru Kimura

Hiroshi Arita

Yasuo Notohara

Yasuhiro Imazu

Tadashi Sodeyama

Takeshi Uchida

Kazuo Tahara

Kenji Kubo

Yasuhiro Kiyofuji

Yasuyuki Sugiura

Naoshi Sugawara

Yoshio Eguchi

Shoji Fukuda

Takashi Shiraishi

Kunio Miyashita

Takeshi Abe

Takeshi Inoue

Toshiyuki Ajima

Shigeo Yoshida

Tomohiko Yasuda

Haruo Koharagi

Takeyuki Itabashi

Hironori Sasaki

Kichio Nakajima

Tohru Kohno

Kei Sakabe

Shuji Katoh

Yoshitaro Ishii

Shigeta Ueda

Osamu Kubota

Susumu Nakano

Takayuki Sato

Fumio Jyoraku

Tomomichi Ito

Ken Takeuchi

Toshikazu Minoshima

Kazuo Suzuki

Hiromu Kakuya

Hisanori Toyoshima

Kazumi Fujii

Tunehiro Endo

Koujirou Yamashita

Shoichi Ito

Hisao Suka

Kohei Honkura

Mitsuhisa Kawamata

Kouichi Yokoura

Tooru Kitayama

Atusi Hosokawa

Yoshiaki Sato

Shoichiro Koseki

Kazuya Tsutsumi

Junichi Sugino

Junji Tamura

Akira Maekawa

Kojiro Yamashita

Hajime Komiyama

Shigeru Kishi

Youji Ikeda

Construction machine including: an inverter; a battery; a battery controller; a main controller controlling the inverter based on limited power modes prescribed; and a display device displaying a remaining battery electric power. The main controller calculates open circuit voltage and battery resistance values of the battery at the state of energy of the battery based on the specification information about the battery and state of energy of the battery which are input from the battery controller, calculates an amount of electric power stored in the battery in each of the limited power modes based on the open circuit voltage value and battery resistance value of the battery as well as limited power and operating voltage prescribed for each of the limited power modes, and outputs a display signal for displaying the amount of electric power stored in the battery in each of the limited power.

Construction machine and battery pack thereof

In order to provide a charge/discharge technology for controlling an assembled battery system without promoting degradation or reduction in the lifetime of the assembled battery system, the assembled battery system includes a function for controlling charge and discharge power of a plurality of units each including a secondary battery and a power converter as one unit, the plurality of units being electrically connected in parallel to each other. When each unit performs charge or discharge by at least one or more times, charge and discharge of the unit are controlled so as not to be performed until a predetermined pause time period elapses.

Battery energy storage system

In a case in which a local solution to current-voltage characteristics is generated by way of a partial shade, it has been difficult to perform control for causing a solar cell to operate at a maximum power point efficiently in terms of power and at a low cost. During steady state operation, an MPPT control unitfor performing the normal hill climbing method is selected, and if the change amount of the output current of the solar cell is greater than or equal to a predetermined threshold, an MPPT control unitfor increasing the variation width of the output voltage of the solar cell to greater than the hill climbing method is selected. By way of such control, it is possible to achieve both efficient operation in a steady state and avoidance of a local solution to a partial shade at a low cost.

Solar power system and control system

Even if requirements for any scale of system constructions occur, a battery system of flexibly responding to the requirements is provided. The battery system comprising a battery module having a plurality of battery cells being connected, a battery pack having a plurality of battery modules being connected either in series or in parallel or both in series and in parallel, and a battery block having a plurality of battery packs being connected either in series or in parallel or both in series and in parallel. They are mutually layered. In the battery system, the battery module, the battery pack, and the battery block are previously prepared as variations of layered basic units. In response to requirements for any scale of system constructions, the basic units are combined accordingly.

Battery system

When detecting a fault of a master control device, a slave control device refers to master-device-line information, and obtains line information to establish a connection with the other master control device. The slave control device transmits connection request information to the master control device extracted from the other master control devices. The other master control device determines whether or not it is connectable with the slave control device that has transmitted the connection request information, and transmits a determination result as connectability information. The slave control device switches a communication line to the other master control device when the received connectability information indicates the connectable status.

Battery control system and battery control method

A wind turbine generator system can regulate the rotational velocity of the wind turbine within an operation range even when the wind velocity suddenly changes and can perform continuous operation of the wind turbine. The wind turbine generator system includes a generator connected to the shaft of the wind turbine and a converter connected to the generator. When the rotational velocity of the wind turbine is within a predetermined range, power outputted from the generator is controlled so as to follow the instruction concerning the generator output given from the wind turbine to the converter. When the rotational velocity of the wind turbine is out of the predetermined range, the power outputted from the generator is controlled without following the instruction concerning generator output given from the wind turbine to the converter.

Wind turbine generator system

A vehicle which evaluates tire wear properly even in a road condition that tires easily slip or lock up. The vehicle, which has a driven wheel and a driving wheel with tires attached thereto, includes: a revolution speed detector for detecting revolution speeds of the driven and driving wheels; a wheel speed detector for detecting wheel speeds of the driven and driving wheels based on the detected revolution speed data of the driven and driving wheels; a wheel speed ratio detector for detecting a wheel speed ratio between the driven and driving wheels based on the detected wheel speed data of the driven and driving wheels; and a tire condition evaluator for outputting an evaluation result indicating that the tire(s) attached to the driven wheel and/or driving wheel is(are) worn when the wheel speed ratio is higher than a preset threshold.

Vehicle having tire wear evaluation system

A wind power generation system includes an excessive current consumption device, an AC input of which is connected between a generator rotor and an excitation converter on a system failure to detect a DC voltage ascent of the excitation converter and operate a shunt circuit on the system failure.

Wind power generation system

In a wind power generation system, an energy consuming unit is connected to a DC part of a generator-side converter. A shunt circuit is connected between the generator-side converter and a rotor of an AC-excited power generator. In the event of system failure, the switching operation of the converter is stopped, the shunt circuit is put into operation, and the energy consuming unit is put into operation so that DC voltage (voltage of the DC part) is maintained within a prescribed range.

Wind power generation system and control method thereof

A pitch controller, uninterruptible power supply, and rotational speed detector are disposed in the rotor in a wind turbine. When a slip ring failure or wire breakage occurs, the pitch controller internally creates a pitch angle command so as to control the pitch angle.

Wind turbine and operating method thereof

In a wind turbine generator system including an AC exciting converter a grid side converter, and a controller configured to control the AC-exciting converter and the grid side converter, the controller operates a short-circuiting circuit when decrease in the grid voltage and increase in the DC voltage are detected.

A wind power generation system wherein procedure for controlling the blade pitch is changed in accordance with the rate of decrease in the amplitude of the grid voltage, and when over current occurs in the grid-side power converter, the grid-side power converter is brought into the gate-blocked condition whereas the generator-side power converter continues its operation.

Wind power generation system and operation method thereof

To shorten a startup interval to reach a synchronizing condition, a phase difference and an amplitude difference between the grid voltage and the stator voltage of one phase of a winding are obtained. The difference in amplitude is decreased prior to or in parallel to synchronizing the stator voltage with the grid voltage. The calculated compensation phase compensation value is used as an initial value for synchronizing at the next synchronizing operation.

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Motoo Futami