Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Mitsubishi Denki K.k.

Mitsubishi Electric Engineering Company, Limited

Tetsuaki Nagano

Kei Terada

Fumio Kumazaki

Masato Koyama

Masanori Ozaki

Masahiko Yoshida

Kazutaka Takahashi

Akihiko Iwata

Hidetoshi Ikeda

Takashi Isoda

Toshiyuki Kaitani

Kiyoshi Maekawa

Yukimori Kishida

Masaya Harakawa

Akira Imanaka

Shinichi Ogusa

Seisuke Tsutsumi

Tsutomu Kazama

Yasushi Ikawa

Yasuhiko Iwai

Shizuo Kumekawa

Yasunobu Harada

Emiko Hayasaka

A converter controllable in regenerative running mode, which is a power converting apparatus capable of suppressing harmonics without increasing the size of a reactor, and reducing power loss and electromagnetic noise. A power converter is configured by directly connecting AC sides of single-phase sub-converters having a DC voltage lower than a DC voltage of a 3-phase main converter to AC input lines of individual phases thereof in series. The main converter is driven by one gate pulse per half recurring cycle and a voltage produced by each sub-converter at AC terminals thereof is controlled to match a difference between an AC power supply voltage and a voltage produced by the main converter at AC terminals thereof, whereby phase voltages of the power converter are generated as the sums of phase voltages of the individual converters.

Power converting apparatus with main converter and sub-converter

A computing unit simulates an ideal operation of a vibration excitation actuator by using at least a model operation parameter and the vibration-excitation movable mass data and calculates a parameter corresponding to acceleration/deceleration thrust for moving the vibration-excitation movable mass. A vibration isolation controller determines a control content of a vibration isolation driving unit based on the parameter corresponding to the acceleration/deceleration thrust and controls an operation of the vibration isolation driving unit so that a force canceling a reaction force, which acts on an apparatus when a vibration-excitation movable mass is moved, acts on the apparatus by moving the vibration isolation movable unit.

Vibration isolation control system

In a servo controller according to the invention, a position feedback correction unit () calculates a first-axis position feedback signal (pmfb) based on a first-axis position (pm) as a self-axis position, and a second-axis position (pm) as an other-axis position; and a deviation between a model position (pa) and the first-axis position feedback signal (pmfb) is inputted from a subtracter () to a position control unit (), which performs positional control to output a velocity command. A velocity feedback correction unit () calculates a first-axis velocity feedback signal (wmfb) from a first-axis velocity (wm) as the self-axis velocity, and a second-axis velocity (wm) as the other-axis velocity; and the velocity control unit () adds a model velocity (wa) and the velocity command outputted from the position control unit (), and subtracts the first-axis velocity feedback signal (wmfb) therefrom, and outputs a feedback torque command (Tfb) based on the corrected velocity command.

Servo controller

An objective is to obtain a high robust position controller and a controlling method therefor, with respect to their technique in which control gain, in order to prevent an overshoot due to frictions, is most suitably adjusted. The position controller having a feedforward system includes: a friction-coefficient-estimated-value setting unit for setting arbitrary friction-coefficient-estimated-values; an overshoot-prevention-gain calculator for determining speed-integral-term feedforward gain, based on estimated friction-coefficient values set by the friction-coefficient-estimated-value setting unit; and a speed feedforward multiplying unit for calculating the product of the speed-integral-term feedforward gain multiplied by a feedforward command value that is based on a positional command; the multiplication product from the speed feedforward multiplying unit being used to reduce the feedforward term.

Position controller and controlling method therefor

In a motor control device according to the invention, upon velocity control of a motor, a superimposed signal generating unitoutputs a superimposed signal idh of a repetitive waveform, such as a triangular wave or a sine wave. A d-axis current command generating unitadds the superimposed signal idh generated by the superimposed signal generating unitto a d-axis current command idc*0 and outputs a d-axis current command idc*. An axial misalignment detecting unit(, and) receives the d-axis current command idc* and a q-axis current command iqc* and outputs an axial misalignment angle estimation value &#x394;&#x3b8;^. An axial misalignment correction unitreceives the axial misalignment angle estimation value &#x394;&#x3b8;^ and an actual detected position &#x3b8;m and outputs a position after correction &#x3b8;m'. Therefore, detection and correction can be performed in real time through calculation at a given timing during a normal operation.

Motor control device

A speed control apparatus of an AC motor a first subtracter for finding toque component voltage saturation amount &Dgr;V from torque component voltage component V &prime; output from a torque component current controller and torque component voltage command V * output from a torque component voltage limiter a first integrator for holding the torque component voltage saturation amount &Dgr;V , a magnetic flux command corrector for outputting magnetic flux command correction amount &Dgr;&phgr; from the held torque component voltage saturation amount &Dgr;V &prime; and rotation angular speed &ohgr; to Cartesian two-axis coordinates, and a second subtracter for subtracting the magnetic flux command correction amount &Dgr;&phgr; from magnetic flux command &phgr; * and outputting magnetic flux correction command &phgr; * .

Speed control device for AC electric motor

There is provided a controlling device for an AC motor having a structure in which a current of a three phase brushless DC motor is detected and then converted to a rotor coordinate system, to separately control a torque split current (q axis) and an exciting split current (d axis), wherein an offset is estimated with a DC component of a multiplied value of the values corresponding to a d axis voltage command which is an output of an exciting split current controller and an electrical angle, and the detected current is compensated for, so that an offset of a current detector may be estimated and compensated for during its operation without stopping its rotation and the motor can rotate smoothly without a torque ripple, even in the case in which the current detector has an offset error or in the case in which an offset changes due to a temperature drift.

Controller for AC motor

The present invention provides a position control unit having a torque command computing device (a position control circuit, and a speed control circuit) for outputting a torque command signal (q-axis current command signal Iq*) according to a positional command signal .theta.m* given from the outside and a positional detection signal .theta.m for an electric motor, and a torque control device (current control circuit) for controlling a torque of the electric motor according to a torque command signal outputted from the torque command computing device, in which the torque control device selects a gain Kqp or a gain Kqi according to whether an absolute value of a positional deviation between the positional command signal .theta.m* and the positional detection signal .theta.m is larger or smaller than a gain switching reference value P for a positional deviation.

Position control unit for electric motor

A position controller includes: a compensation torque control circuit which outputs a second torque signal T.sub.2 * and an initial value of an integration torque T.sub.iset on the basis of a real speed signal .omega..sub.M, a rotation angle instruction signal .theta..sub.M *, a real rotation angle signal .theta..sub.M, an integration torque signal T.sub.i of a speed control circuit, and a reference .theta..sub.drp *; a speed control circuit which outputs a first torque signal T.sub.1 * and the integration output T.sub.i on the basis of a speed instruction signal .omega..sub.M * and the real speed signal .omega..sub.M ; an adder which adds the first torque signal T.sub.1 * to the second torque signal T.sub.2 * and outputs a torque instruction signal; and a torque control circuit which controls the torque of the motor in accordance with the torque instruction signal.

Position controller for an electric motor

A controller for an electric motor, wherein a differential signal for a speed instruction signal is obtained by a differential circuit, a control signal is obtained by a first speed control circuit, and both signals are summed to obtain a first torque signal. A simulated speed signal is obtained from the first torque signal by a torque simulating circuit and a mechanical system simulating circuit. A second torque signal is obtained by a second speed control circuit. The first and second torque signals are summed by an adder to obtain a torque instruction signal, and the electric motor is controlled so that the generated torque follows the torque instruction signal.

Electric motor controller having independent responses to instructions

A positioning control apparatus for accurately positioning a tool and workpiece and for reducing the vibration related to positioning. The system comprises a machining table fitted with a workpiece and designed to be movable on a bed. A first detector detects the acceleration of the machining table in a moving direction, and a second detector detects the acceleration in the moving direction of a tool fitted to a column that also is coupled with the bed. The outputs of the first and second detectors are used to suppress the relative vibration of the workpiece fitted to the machining table and the tool fitted to the column in the moving direction.

Method and apparatus for controlling the positioning and reducing

A position controller for controlling an electric motor comprises first position control circuit which provides first speed signal, second position control circuit which controls a mechanical system simulating circuit and provides second speed signal, an adder which adds the first and second speed signals to provide third speed control signal, first speed control circuit which receives the third speed signal and provides first torque signal, second speed control circuit which provides second torque signal, third speed control circuit which provides third torque signal, and an adder which adds the first, second and third torque signals to provide final torque signal. The output torque of the electric motor is controlled so that the output torque coincides with a torque represented by the final torque signal. The position controller has high-speed response characteristics, is capable of suppressing mechanical vibrations and maintains a constant response frequency even if the moment of inertia of a load machine driven by the electric motor varies.

Position controller for controlling an electric motor

A closed-loop feedback control system is disclosed for controlling an operation of a load. An actual operation signal is subtracted from a reference operation signal to produce a resultant signal which is used to control the operation of the load. A filter unit, such as a notch filter, operates to suppress any machine resonance frequencies found in the operation signal due to load fluctuations, machine variations, operating environment changes, deterioration with age, etc. A filter coefficient of the filter unit is adjusted so that any fluctuation in the resonance frequency can be suppressed effectively.

Closed-loop feedback control system having an adaptive filter

An induction motor controller which compensates for changes in primary resistance values and secondary resistance values that occur with changes in temperature. Multi-phase current and voltage values are detected at the motor input and converted into primary currents and voltages within an orthogonal system and are used to calculate equivalent and estimated equivalent values of magnetic flux. The flux values are used to generate an estimated value of rotary angular velocity of the induction motor, which is used as a basis for controlling in a feedback manner the generation of the command signals for the motor. The magnetic flux values generated in response to the orthogonal voltage and current values are sensitive to a predetermined primary resistance value and a predetermined secondary resistance value. Circuits for automatically changing the predetermined primary resistance value alone or together with the predetermined secondary resistance value, in response to ones of the flux values, are provided. As a result of compensation for the change in the predetermined resistance values as a function of temperature, accurate control of the angular velocity of the motor can be obtained.

Growing community of inventors

Tokyo, Japan

Tetsuaki Nagano