Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Kazuhiko Tsutsui

Mitsuyasu Kachi

Shinichi Furutani

Akiko Tabuchi

Yoji Tsutsumishita

Jun Hattori

Manabu Ohashi

Jyun Sawaki

In the case where DC power from a DC power supply is converted to AC power by an inverter and supplied to an AC motor, a power compensator is connected in parallel with a DC power input portion of the inverter, and a control device of the power compensator charges/discharges a power storage device to perform a power compensation process A when power demand for the AC motor exceeds a predetermined value, and takes into account power allowance which can be inputted and outputted from the DC power supply to the power storage device and performs a power storage adjustment process B of performing auxiliary charge of the power storage device within the range of the power allowance when the power compensation process A is unnecessary.

AC motor driving apparatus

In a case where a motor cannot follow up a position designated by a position instruction in a velocity operation mode, when an operation is performed in a constant power operating region, or when a voltage is saturated, a limit is put on a position deviation in a motor control apparatus. A correction position deviation amount, by which the motor cannot follow up the position instruction, is subtracted from the position deviation. Further, a motor position-within-one-revolution deviation in the subtracted correction position deviation amount is corrected in a region in which the characteristic of torque is improved. Consequently, the followingness of the motor to the motor position-within-one-revolution in the position designated by the position instruction is ensured.

Motor controller and motor controlling method

A motor control device comprises: a current limiterfor limiting a current-instruction signal Ir for a motorand for turning a limiting signal L from off to on when the current-instruction signal Ir reaches a predetermined value; a model-position-generating parthaving a model of an equivalent position-control system that includes characteristics of the motor control deviceand a control target object, and calculating rotational position of the motoras a model-position signal &#x3b8;m by inputting to the model a position-instruction signal &#x3b8;r; a correctional acceleration-generating partfor generating a correctional acceleration signal &#x3b1;se based on a correctional position deviation &#x3b8;se when the limiting signal L turns on; and a position-instruction-generating partfor generating the position-instruction signal &#x3b8;r based on an acceleration deviation &#x3b1;r that is equal to the difference between the original-acceleration-instruction signal Va and the correctional acceleration signal &#x3b1;se.

Motor control device

An ideal position is calculated based on an ideal servo system model, the difference between the calculated ideal position and the actual position feedback is multiplied by a predetermined gain only for a predetermined time from the direction reversing time of the ideal position, and the result is added to the speed command as the correction amount, so that variations in the correction effect, caused by the effect of a secular variation of the friction amount and the work condition difference is suppressed and even in a machine system with large elastic change in torsion of a ball screw, a seal material, etc., undercut caused by torsion restoration after the correction, etc., is suppressed and a servo system is prevented from becoming unstable.

Servo controller and method

Magnitudes of a sine-wave component and a cosine-wave component of a periodical disturbance are estimated in real time during motor rotating, the sine-wave component and the cosine-wave component at the frequency of the disturbance estimated are combined, and the result is added to a current command as a correction value in real time during the normal motor driving for controlling servomotor, thereby suppressing the effect of the periodical disturbance.

Servocontrol device

In a servo control apparatus in which a machine system is driven by a servo motor, a phase compensation device is provided. The phase compensating device calculates a speed component (phase delay compensation signal) corresponding to a phase delay caused by a mechanical resonance suppressing filter which is provided so as to suppress resonance and mechanical vibrations, produced by a characteristic frequency owned by the machine system. While such a signal obtained by adding this speed component (phase delay compensation signal) to an actual motor speed is used as a speed feedback signal for a control operation, unstable conditions of a servo system, which are caused by the phase delay caused when the mechanical resonance filter is applied, are suppressed, and a high gain of the servo control apparatus is realized.

Servo control apparatus

According to the present invention, in a first acceleration after power is turned ON, currents flowing through U-phase and V-phase of a servo motor output terminal are detected, and misconnection of the motor output terminal is detected by monitoring a pattern of the current wave form.

Growing community of inventors

Tokyo, Japan

Kazuhiko Tsutsui