Hitachi, Ltd.

Naoto Ohnuma

Tsunehiro Endo

Hiromi Inaba

Takeshi Kondo

Yasutaka Suzuki

Sadao Hokari

Ikuo Yamato

Daigo Kaneko

Toshifumi Yoshikawa

Shinsuke Inoue

Naoki Takayama

Toshisuke Mine

Takao Kishikawa

Kohichiroh Ide

Gorou Satou

Tomoaki Terunuma

An elevator according to an aspect of the present invention includes a car speed detection device that measures car speed, an emergency braking device that comes into press contact with a guiderail and emergently stops a car when the car speed exceeds a threshold, an electric actuating unit that electrically actuates the emergency braking device, a battery that supplies electric power when commercial power supply is interrupted, and a safety control unit that monitors abnormality of the elevator and controls operation of the electric actuating unit. The safety control unit measures remaining power of the battery when the electric power is supplied from the battery, determines operation propriety of the emergency braking device at commercial power supply restoration time based on transition of battery remaining power, and controls operation of the electric actuating unit at the commercial power supply restoration time based on content of the determination.

Elevator and control method for elevator

In order to control the position of a mobile body without using a position detector, a magnetic pole position of a rotor of a synchronous motor is estimated based on electrical quantities in relation to electric power supplied to the synchronous motor and then the mobile body position is estimated based on the estimated magnetic pole position.

Apparatus, method or system for controlling mobile body

A driving system for driving an AC motor, which is capable of promptly switching to an individual inverter operation mode, wherein a control instruction for each of a plurality of power converters is generated by summing outputs of a plurality of current compensation units connected in parallel, and each of the plurality of current compensation units makes compensation to reduce a deviation of a detected output current value of an associated power converter from a current instruction value to be outputted from the power converter to zero.

Driving system for driving AC motor

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Hitachi, Japan

Naoto Ohnuma