Mitsubishi Electric Corporation

Yuya Tsuchimoto

Isao Kezobo

Akira Furukawa

Shunsuke Nakajima

Tatsuya Mori

Yoshihiko Kimpara

Genki Fujii

Satoru Akutsu

Yuichiro Nakamura

Chiaki Fujimoto

Yuji Takatsuka

Isao Sonoda

Kenta Kubo

An angle detector including; a magnet being mounted on a rotation axle and that has a first track magnetized in P pole-pairs and second track magnetized in Q pole-pairs, a first hole device group that senses magnetic flux from the first track, a second hole device group that senses magnetic flux from the second track, a first detection unit that outputs an M-step absolute angular signal through division of one electric-angle rotation into M sections, a second detection unit that outputs an N-step relative angular signal through division of each of the M divided sections into N sections, an angle calculation unit that divides the one electric-angle rotation into [M×N] sections and calculates an [M×N]-step electric angular signal, based on the absolute angular signal and the relative angular signal, and an angle correction unit that outputs a correction angle supplemented so as to smooth the electric angular signal.

Angle detector, AC-rotating-machine controller, and electric power steering apparatus

A motor temperature and torque estimation device comprises: a temperature sensor; a losses estimation circuitry to estimate an iron loss; a first temperature estimation circuitry to estimate a first magnet temperature from the estimated iron loss and a sensor's detected temperature; a second temperature estimation circuitry, to input into a magnet's magnetic flux calculator thereinside motor's modified inductance, to estimate a second magnet temperature from magnet's magnetic flux calculated through voltage equations; a magnet-temperature estimation circuitry to estimate a motor's magnet temperature from the first and second magnet temperatures; a magnet's magnetic estimation circuitry to estimate magnetic flux based on the calculated/modified one, the motor's estimated magnet temperature and temperature characteristics, and to output the estimated magnetic flux into the losses estimator; and a torque estimation circuitry to estimate torque based on the estimated magnetic flux and iron loss, wherein a motor's magnet temperature(s) and torque are estimated.

Motor temperature and torque estimation device, and motor control device

A permanent-magnet-synchronous electric motor control device includes: a reference voltage value calculation unit for calculating a reference voltage value; an output voltage value calculation unit for calculating an output voltage value on the basis of a voltage command; a current weakening command calculation unit for calculating a current weakening command on the basis of the reference voltage value and the output voltage value; a voltage command calculation unit for calculating the voltage command on the basis of the current weakening command; and a power converter for supplying power to a permanent-magnet-synchronous electric motor on the basis of the voltage command. The current weakening command calculation unit calculates the current weakening command in which a high-frequency component is amplified on the basis of the difference between the reference voltage value and the output voltage value.

Permanent-magnet-synchronous electric motor control device and electric power steering device provided with same

An electric power steering apparatus includes: a torque sensor configured to detect a steering torque of a driver; a motor configured to assist in a steering force of the driver; a rotation angle estimation unit configured to estimate a rotation angle of the motor to output an estimated angle; a correction signal calculation unit configured to calculate a correction signal based on the steering torque; a frequency separation unit configured to separate the estimated angle into a first frequency component and a second frequency component; an estimated angle correction unit configured to calculate, as a control angle, a value obtained by adding a second-frequency-component corrected signal, which is obtained by correcting the second frequency component based on the correction signal, to the first frequency component; and an electric power supply unit configured to supply electric power to the motor based on the control angle.

Electric power steering apparatus and electric power steering control method

A control device includes: a first power converter applying a voltage to a first winding; a second power converter applying a voltage to a second winding; a first power supply circuit supplying power to the first power converter; a second power supply circuit supplying power to the second power converter; a current command calculator; a first current controller; and a second current controller. The second power supply circuit supplies power at a voltage higher than a voltage of the first power supply circuit. The current command calculator calculates a first voltage usage state, which is an indicator value correlated with a magnitude of the output voltage of the first power converter with respect to a power supply voltage output at a time of supply of power by the first power supply circuit, and calculates the second current command based on the first voltage usage state.

Permanent magnet synchronous electric motor control device, electric power steering device, and electric vehicle

An electric power steering apparatus including: a steering torque detector to detect a steering torque of a driver; a motor to assist a steering force of the driver; an estimated speed calculator to calculate an estimated speed, which is an estimated value of a rotation speed of the motor; an estimated speed corrector to correct the estimated speed based on the steering torque; an estimated angle calculator to calculate an estimated angle of the motor by integrating the estimated speed after the correction; and an electric power supply to supply electric power to the motor based on the estimated angle, wherein the estimated speed corrector corrects the estimated speed when a determination signal, which is based on a value obtained by removing a frequency component of steering of the driver from a derivative of the steering torque, the steering torque, and the estimated speed have the same signs.

Electric power steering apparatus and method for controlling electric power steering

A control device for a motor, comprising: a power converter for performing ON/OFF control on an upper switching element and a lower switching element in accordance with a drive command from a current controller, and thereby supplying power to a motor; a current sensor provided to the lower switching element; and a fault determining unit for determining a fault in the current sensor. When the lower switching element for each phase is OFF, the current sensor detects the current error in each phase. The fault determining unit obtains a current error determination value on the basis of the value obtained by converting, to Cartesian coordinates, the current error for each phase or the magnitude of the sum of current error vectors for each phase in which the value for the current error for each phase is held as the magnitude, and determines a fault.

Control device for motor, and electric power steering system

When the state where steering torque detected by a torque detection unit is normal and the value of the steering torque is the same as or larger than a threshold value continues, an assist command generation unit that generates an assist command corresponding to steering torque produced by a driver limits the assist command; a failure determination unit includes a first failure determination unit that performs determination on a failure regardless of the limitation of the assist command and a second failure determination unit that performs determination on a failure while the assist command is limited, and stops driving of a motor when the second failure determination unit determines that there exists a failure.

Electric power steering apparatus

When there is an error between an actual resistance value of an AC rotary machine (ACRM) and an estimated resistance value estimated from a detected external temperature of the ACRM, the ACRM cannot be rotated smoothly. In view of this, provided are a control device for an ACRM and the like, including a resistance value estimation unit () configured to calculate an estimated resistance value (Rest) by adding to a basic estimated resistance value (Rest), which is a value obtained by estimating a resistance value from a detected external temperature of the ACRM, an estimated resistance correction value (Radd), which is determined such that a range that can be taken by an error (&#x394;R) of the resistance value estimated in advance falls within a range of the error of the resistance value that enables the ACRM to be rotated smoothly.

AC-rotary-machine control device and electric power-steering system provided with AC-rotary-machine control device

This AC rotating machine control device includes: power limiting meansfor limiting drive power supplied for driving the AC rotating machine; and power feed meansfor, when sensor abnormality determination meansdetermines that the rotational position sensor is abnormal, on the basis of the estimated rotational position, supplying the AC rotating machine with power obtained by adding rotational position estimation power supplied for the rotational position estimation meansto estimate the rotational position, to the drive power limited by the power limiting means, wherein the power limiting meanslimits drive current at least during a predetermined period since the sensor abnormality determination meansdetermines that the abnormality occurs until estimated error of the estimated rotational position falls within a predetermined range.

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Tokyo, Japan

Yuya Tsuchimoto