Mitsubishi Denki Kabushiki Kaisha

Yasushi Ikawa

Seisuke Tsutsumi

Masahiro Kimata

Tetsuaki Nagano

Masanori Ozaki

Masahiko Yoshida

Fumio Kumazaki

Shizuo Kumekawa

Akira Shima

Kiyonari Kawajiri

A power converter includes a first sampling devicewhich samples a first command current value for a power conversion deviceduring a second cycle and produces a second command current value; a second sampling devicewhich samples a first detected current value pertaining to a loadand produces a second detected current value; a command voltage value calculatorfor calculating a command voltage value from the second command current value and the second detected current value; a comparatorfor comparing the second command voltage value with a triangular wave carrier signal, to thereby produce a first pulse width modulation (PWM) signal; and a multi-pulse prevention device. The multi-pulse prevention devicehas inversion detection device for detecting inversion of the first PWM signal, and inversion inhibition device for driving the power conversion devicethrough use of a second PWM signal which prevents inversion of the first PWM signal, on the basis of a result of detecting operation performed by the inversion detection device.

Power converter employing pulse width modulation control

A motor driving control apparatus comprises a current detecting section for detecting an output current from an inverter section; a current control section for outputting a voltage instruction to a PWM section from the detected current value, a current instruction from an external device, and from a positional signal of an encoder connected to a motor; and a PWM section for outputting a PWM signal to the inverter section according to a voltage instruction, and an encoder I/F section for receiving a positional signal for the encoder is provided in an external interface section, the current control section and PWM section are provided in an N potential control section connected to the external interface section, and the external interface section transmits the current instruction and the positional signal inputted into the encoder I/F section through serial communications via an insulating section.

Motor driving control unit and motor driving control method

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

An apparatus and method for controlling driving of a apparatus such as a motor. A signal representing the position and/or velocity of the motor is received by a drive control unit. A microprocessor in the drive control unit provides a division ratio signal and a rotation judging signal to a clock pulse divider and two-phase pulse generator, respectively, and also calculates the velocity of the apparatus in accordance with the condition data. The clock pulse divider divides a clock pulse signal in accordance with the division ratio signal and outputs a divided clock pulse signal. The two-phase pulse generator generates two-phase pulses having a 90-degree phase shift of a given polarity with respect to one another in accordance with the divided pulse signal, and reverses the polarity of the phase shift in accordance with the rotation judging signal. The microprocessor further outputs a control signal to control driving of the apparatus in accordance with the calculated velocity and the two-phase pulses.

Drive control apparatus

A system for inverter control of a servo motor where in the inverter is connected to a velocity control section and a position detection section is connected to the servo motor. Primary and back-up power for operating the velocity control section and the position detection section is provided by power sources that are located in the velocity control section and are connected to the position detection section by cables. The cables used to provide signal transmission between the position detecting section and the velocity control section are switched by relays to transmit the power of a power failure back-up power supply at the time of a power failure. Also, a transmission signal transmitted from one of the position detecting section and the velocity control section to the other via a first cable connection is returned via a second cable connection and a connection fault may be judged depending on whether or not the return signal matches the transmission signal.

Growing community of inventors

Aichi, Japan

Yasushi Ikawa