Hitachi, Ltd.

Hitachi Industrial Equipment Systems Co., Ltd.

Hitachi Automotive Systems, Ltd.

Renesas Electronics Corporation

Hitachi Car Engineering Co., Ltd.

Hitachi Astemo Ltd.

Hitachi Appliances, Inc

Renesas Technology Corp.

Kokusan Denki Co., Ltd.

Japan Servo Co.,ltd.

Hitachi Home and Life Solutions, Inc.

Yoshitaka Iwaji

Kazuaki Tobari

Tsunehiro Endo

Kiyoshi Sakamoto

Junnosuke Nakatsugawa

Shigehisa Aoyagi

Masaki Hano

Daigo Kaneko

Minoru Kurosawa

Yasuhiko Kokami

Kohji Maki

Yasuaki Aoyama

Ryoichi Takahata

Yusaku Onuma

Satoru Kaneko

Toshiyuki Ajima

Naoki Okamoto

Yasuo Notohara

Yuhachi Takakura

Atsuhiko Nakamura

Takuya Sugimoto

Tomofumi Okubo

Tatsuo Ando

Satoshi Sumita

Takeshi Umetsu

Agnes Hadinata

Hiroshi Fujii

Hiroyuki Tomita

Mitsuo Sasaki

Hiromi Inaba

Yukio Kawabata

Norihisa Iwasaki

Koichiro Nagata

Kouki Yamamoto

Masakazu Hase

Ryozo Masaki

Yoshiyuki Taguchi

Chikara Tanaka

Takahiro Suzuki

Yoshiaki Kurita

Hajime Uematsu

Toshifumi Sakai

Takashi Okada

Hideki Miyazaki

Hiroshi Watanabe

Kinya Nakatsu

Ryoso Masaki

Yuji Enomoto

Akihiro Nakamura

Yasuo Morooka

Toshiaki Okuyama

Takafumi Hara

Takashi Nakahara

Masahiro Hori

Hisashi Tanie

Naoki Sakurai

Tetsuo Kojima

Takayoshi Nakamura

Akiyoshi Komura

Shinji Sugimoto

Hirooki Tokoi

Daisuke Kori

Houng Joong Kim

Kim Houng Joong

Kohei Myoen

Akeshi Takahashi

Motomi Shimada

Yoshifumi Kuwano

Tomoyuki Hanyu

Taizou Miyazaki

Takumi Hisazumi

Hidefumi Shirahama

Guangbin Zhou

Akio Takemori

Hironori Ohashi

Hiroaki Taka

Kento Mochizuki

Masahiro Tobise

Yoshimi Sakurai

Tetsuji Kato

Dongsheng Li

Junji Kato

Seikichi Masuda

Kenta Deguchi

Takao Yanai

Midori Takaoka

Tsunehiro Endou

Takeshi Shinomiya

Rikio Yoshikawa

Kentaro Oi

Junki Isobe

Tatsuo Matsumura

Noriaki Yamada

Hirokazu Nagura

Kohei Matsushita

Yuuta Iwase

Masato Ohya

Yoichiro Arakawa

Fusao Houjyou

This power conversion device has: a current measurement unit for measuring phase current; a current vector calculation unit for calculating a current vector by performing 3-phase to 2-phase conversion on the phase current; an amount-to-be-analyzed calculation unit for calculating, on the basis of the current vector, an amount to be analyzed; and a feature amount waveform extraction unit for extracting a waveform in a specific frequency range on the basis of the amount to be analyzed.

Power conversion device, rotating machine system, and diagnosis method

A power conversion device includes a harmonic voltage generation unit that superimposes dc-axis and qc-axis harmonic voltages on dc-axis and qc-axis voltage commands in accordance with a switching signal; and an inductance estimation unit that estimates dc-axis inductance and qc-axis inductance on a basis of dc-axis and qc-axis harmonic currents, amplitude values of the harmonic voltages, and the switching signal.

Power conversion device

A power conversion apparatus controls a load apparatus by position sensorless vector control. The power conversion apparatus includes: a current detection unit configured to detect a current passing through the load apparatus; a current detection arithmetic unit configured to calculate a harmonic current component on a dc-axis as a control axis and a harmonic current component on a qc-axis, based on the detected current; a saliency ratio estimation unit configured to output a saliency ratio estimated value based on the harmonic current component on the dc-axis and the harmonic current component on the qc-axis; and a saliency ratio control unit configured to output a current component that increases or decreases a current command value on a d-axis of a rotor coordinate system, based on a deviation between the saliency ratio estimated value and a predetermined saliency ratio.

Power conversion apparatus

An object of the present invention is to provide an electric power steering apparatus capable of improving reliability of a drive device for a three-phase synchronous motor without increasing a cost of the drive device. A control device for controlling an electric power steering apparatus according to the present invention is a control device for controlling an electric power steering apparatus using a three-phase synchronous motor as a force assisting in a steering operation, includes: a rotational position estimation unit that estimates a position of a rotor of the three-phase synchronous motor on the basis of a neutral point potential or a virtual neutral point potential of the three-phase synchronous motor; and a command signal computing unit that computes a command signal to the three-phase synchronous motor on the basis of the position of the rotor estimated by the rotational position estimation unit.

Control device for electric power steering apparatus and electric power steering apparatus

An induction motor overheat monitoring method and device detects overheating of an induction motor from a detection value of a current sensor. A resistance calculation relationship data indicating a relationship between a resistance and a feature amount at the time of starting of the induction motor and a determination reference value for determining overheating are stored in advance. At each starting, a current of the induction motor is detected, a signal regarding a phase angle difference is calculated, and a feature amount of the motor is calculated from the signal regarding the phase angle difference. Further, a resistance of the induction motor is calculated by using the feature amount of the motor and the resistance calculation reference data stored in advance. Then, a temperature of the induction motor is calculated from the resistance of the induction motor, and it is determined if the motor is overheated.

Induction motor overheat monitoring method, induction motor monitoring device, and induction motor control system

Provided is an AC electric motor control device capable of detecting, in an AC electric motor drive device, abnormal operation of an AC electric motor or abnormal operation due to, for example, a sudden change of a load without an erroneous operation regardless of the operational state of the AC electric motor. When driving a three-phase AC electric motor by an inverter, inside a controller, an electric motor constant is calculated using at least one of the current, voltage, and rotational speed of the electric motor and the variation of the constant value is analyzed, thereby detecting abnormal operation of the electric motor or abnormal operation of a load device connected to the electric motor. In order to analyze the constant, a variation to be determined to be abnormal is preset or an abnormal value is calculated in comparison with the accumulated values of past constant changes. Alternatively, only the variation of the constant calculated in the controller is extracted to detect abnormality.

AC electric motor control device

A rotating machine drive system includes: a rotating machine that includes a plurality of windings; a phase current detecting circuit that detects a phase current to be supplied to the rotating machine; an inverter device that includes an inverter circuit that converts DC power from a DC power supply into AC power, and a control device that controls power conversion being performed by an inverter main circuit on the basis of the phase current detected by the phase current detecting circuit, the inverter device operating the rotating machine at a variable speed; and a winding switching device that switches connections of the plurality of windings in accordance with a command from the control device. In a case where the rotation zone of the rotating machine is to be changed, the control device stops the current supply from the inverter circuit to the rotating machine, and switches the rotation zone of the rotating machine from a low-speed rotation zone to a high-speed rotation zone, or from the high-speed rotation zone to the low-speed rotation zone, on condition that a line internal voltage induced by a field magnetic flux of the rotating machine is lower than the DC voltage of the DC power supply.

Rotating machine drive system

In a motor drive device, a phase compensation amount calculation unitcalculates a phase compensation amount &#x394;&#x3b8; for compensating a voltage phase &#x3b8;v* when a control mode is switched in a control selection unit. The control selection unitoutputs the three-phase voltage command Vuvw* according to any one of the plurality of control modes based on the modulation factor Kh*, the voltage phase &#x3b8;v*, and the phase compensation amount &#x394;&#x3b8;. A PWM control unitoutputs gate signals Gun, Gup, Gvn, Gvp, Gwn, and Gwv based on the three-phase voltage command Vuvw* and a rotor position &#x3b8;d. The inverterhas a plurality of switching elements, and controls the plurality of switching elements based on gate signals Gun, Gup, Gvn, Gyp, Gwn, and Gwv to drive the AC motor

Motor drive system

A power conversion device according to the present invention is connected to a rotating machine comprising an armature coil and supplies and receives power. The power conversion device has a function for: collectively applying voltage pulses to the armature coil or coils for one or more specific phases of the rotating machine, sampling the current values of the specific phases from the start of the rising or falling of the voltage pulses until a designated delay time, detecting variation in the capacitance of an insulation member of the armature coils of the specific phases of the rotating machine from variation from a normal state of the current values, and diagnosing insulation degradation.

Power conversion device, rotating machine system using same, and diagnosis method for same

To enable overmodulation control having high controllability and low noise characteristics, a control device of an AC motor includes an inverter for driving an AC motor and a controller for controlling the inverter by pulse width modulation. The controller, when over-modulating the inverter, limits the amplitude of the voltage command in the pulse width modulation to a predetermined upper limit value or less.

Control device and control method for AC motor and AC motor drive system

According to the present invention, in position sensorless control for switching between a 120-degree energization scheme for a low-speed region and a 180-degree energization scheme for a mid-to-high-speed region, stable and highly accurate speed control characteristics are provided by suppressing speed deviation &#x394;&#x3c9;r in the low-speed region, and by preventing current jump-up caused by a discontinuous rotational speed occurring during switching to the mid-to-high-speed region. In the case of driving in the 120-degree energization scheme, a voltage command value is corrected such that an estimated speed value or a detected speed value follows a speed command.

Synchronous motor control apparatus

A highly reliable electromechanical integral motor is provided. In the electromechanical integral motor including an axial gap type motor and a power conversion control device, the power conversion control device is mounted on an end bracket portion of the motor. Additionally, a space is provided between the end bracket portion of the motor and the power conversion control device. Further, the end bracket portion of the motor and the power conversion control device are fixed by a plurality of fixing members, and at least one set of the plurality of fixing members is disposed to be spaced apart from each other.

Electromechanical integral motor

Disclosed are a motor control system and a motor control method that allow the balance of evaluation values in a trade-off relationship to be easily adjusted. The motor control system includes: an inverter () that applies AC voltage to a motor (); a control unit () that generates a voltage command for AC voltage in response to a control command; and a feedback unit () that applies a correction value to the control unit. The feedback unit estimates a plurality of evaluation values from a state quantity using a plurality of regression formulas, where at least one state quantity (x1, x2) of the motor is an input variable and a plurality of evaluation values (y1, y2) of the motor or a motor-driven object () are output variables, calculates an evaluation function with the estimated plurality of evaluation values as arguments, and generates a correction command on the basis of a calculation value resulting from the evaluation function.

Motor control system and motor control method

A control device of a synchronous electric motor includes: the synchronous electric motor with three-phase stator windings Y-connected; a detection unit that detects a neutral point potential which is a potential at a Y connection point; and an inverter that drives the synchronous electric motor. The control device of the synchronous electric motor which controls the synchronous electric motor using the inverter, includes a measurement mode in which the neutral point potential is detected in a state in which the synchronous electric motor is energized by an AC current and controls the synchronous electric motor based on a value of the neutral point potential detected in the measurement mode.

Control device of synchronous electric motor, integrated motor system, pump system, and positioning system

Provided is a control device of an AC motor, including: an inverter including a switching element; switching control means for controlling the switching element; and phase detection means for detecting a rotor phase of an AC motor, wherein the switching control means controls the switching element so that a voltage waveform of the inverter has half-wave symmetry in an interval of a width centering on a fundamental voltage phase of 180 deg&#xb1;180 deg, the switching control means controls the switching element so that a harmonic voltage phase of the inverter becomes variable on the basis of a fundamental voltage-rotor phase difference which is a difference between a fundamental voltage phase and the rotor phase of the AC motor, and the switching control means controls the switching element so that a harmonic voltage amplitude of each order of the inverter is inversely proportional to the order.

Control device of AC motor

Growing community of inventors

Hitachinaka, Japan

Yoshitaka Iwaji