Matsushita Electric Industrial Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Taro Kishibe

Hiroshi Murakami

Yasufumi Ikkai

Takahiro Masuda

Kazushige Narazaki

Haruhiko Kado

Yusuke Shimogaki

Hiromi Tanoue

Toshiyuki Tamamura

Hideyuki Kishida

Yukihiro Okada

Subrata Saha

Noriyoshi Nishiyama

Yoshiaki Igarashi

Tomokuni Iijima

Shinichiro Kawano

Masayuki Shinto

Hisakazu Kataoka

Kouji Kuyama

Mikio Hirano

Shigenori Uda

Daisuke Sonoda

Koji Kameda

Yukinori Maruyama

Osaaki Morino

Hideaki Ichikawa

Hirokazu Yamasaki

Hiroshi Ozaki

Shuichi Yamane

Akio Ando

Tomoya Hosokawa

Satoru Doi

Masashi Senoo

Yuko Otani

Hisashi Ooto

Ryuhei Watabe

Yuichiro Sadanaga

Shin'ichi Yoshimura

A cut-off circuit diagnostic device includes a motor control module that controls a motor, and an external safety module that is detachably attached to the motor control module. The motor control module includes: a motor drive unit that has an inverter circuit for controlling a voltage applied to the motor by pulse width modulation control and a drive circuit for driving a power element of the inverter circuit; a cut-off circuit that cuts off power supply to the drive circuit; and a first cut-off circuit diagnostic unit that has a first diagnosis pulse generator for generating a first signal to control the cut-off by the cut-off circuit and that detects whether or not the power supply to the drive circuit is cut off according to the first signal. The external safety module includes a second cut-off circuit diagnostic unit that has a second diagnosis pulse generator for generating a second signal to control the cut-off by the cut-off circuit and that detects whether or not the power supply to the drive circuit is cut off according to the second signal. The motor control module further includes a function switching unit that supplies the second signal to the cut-off circuit when the external safety module is attached to the motor control module, and supplies the first signal to the cut-off circuit when the external safety module is not attached to the motor control module.

Cut-off circuit diagnostic device

A diagnostic apparatus includes a control device and an extension device connectable to the control device. The control device includes one or more cutoff blocks that switch between allowing and cutting off power supply to a load, a first diagnostic pulse generator that generates a diagnostic signal indicating that the power to the load is to be cut off, a first cutoff diagnosing device that detects a supply voltage to the load, and an extension device detector that determines whether the extension device is connected to the control device. The extension device includes a second diagnostic pulse generator that generates a diagnostic signal, and a second cutoff diagnosing device that detects a supply voltage to the load.

Diagnostic apparatus

A motor control device that detects a motor current through &#x394;&#x3a3; AD conversion includes a stop signal generator and a stop signal controller. When a difference between a maximum value and a minimum value of three phase voltage command values to be applied to a motor is smaller than or equal to a predetermined threshold, a stop signal that causes the &#x394;&#x3a3; AD conversion to stop is output with a delay by the time corresponding to a delay in current detection while a leakage current caused by on and off of a power conversion element is occurring.

Motor control device

A motor drive device includes: an inverter circuit; a drive circuit which receives voltage supplied from a control power source; a first cutoff circuit which cuts off voltage supply from the control power source to the drive circuit; a second cutoff circuit connected between the first cutoff circuit and the drive circuit; a voltage detection circuit which detects a detection voltage corresponding to the voltage supplied from the control power source and which is capable of changing the detection voltage; a comparison circuit which, upon determination that the detection voltage is not within a predetermined range, cuts off the first cutoff circuit; and a diagnosis circuit which diagnoses the first cutoff circuit. The diagnosis circuit causes the comparison circuit to cut off the first cutoff circuit, diagnoses the first cutoff circuit, and upon diagnosing the operation of the first cutoff circuit as being abnormal, cuts off the second cutoff circuit.

Motor drive device

A motor control device has a motor current detector for detecting current in windings to control the operation of a motor with a stator having three-phase windings. The motor control device includes a digital controller for outputting a PWM switching signal, a power converter for applying drive voltage to the windings using the PWM switching signal, a motor current detector for converting current flowing in the windings to analog voltage, a &#x394;&#x3a3; AD converter for converting the analog voltage to a 1-bit digital signal, an AD conversion decimating filter for generating a detected motor current value from the 1-bit digital signal, a clock generator for generating a clock for the &#x394;&#x3a3; AD converter and the AD conversion decimating filter, and a stop signal generator for generating a clock stop signal for stopping the clock of the clock generator for a predetermined period. The stop signal generator generates the clock stop signal with a predetermined pulse width based on a timing of the PWM switching signal, and the clock generator stops the clock for a period of the predetermined pulse width, using the clock stop signal.

Motor control device and motor control method

A motor control device, which receives at least two emergency stop signals, includes an LSI, a PWM signal transmission circuit, a drive circuit, and an inverter circuit. The LSI generates PWM signals. The PWM signal transmission circuit transmits the PWM signals. The drive circuit generates inverter drive signals. The inverter circuit includes a P-side power switching device and an N-side power switching device. The drive circuit includes a P-side drive circuit for driving the P-side power switching device, and an N-side drive circuit for driving the N-side power switching device. One of the emergency stop signals is inputted to the P-side drive circuit and the PWM signal transmission circuit. The other emergency stop signal is inputted to the N-side drive circuit and the PWM signal transmission circuit. In response to the receipt of an emergency stop signal, the PWM signal transmission circuit stops transmitting the PWM signals, and the drive circuit stops outputting the inverter drive signals.

A position detector has a peak detector for detecting peak values of an Asignal and a Bsignal serving as output signals of an analog to digital (AD) converter, an offset/amplitude correction section for generating an Asignal and a Bsignal by correcting offsets and amplitude errors using the peak values detected by the peak detector, and a position data conversion section for converting the sinusoidal signals of an A phase and a B phase into position data.

Phase correction circuit of encoder signal

A discrete rotor position estimation method for a synchronized reluctance motor is provided. A d.c.-link voltage Vand a phase current Iare sensed. A flux-linkage &#x3bb;of an active phase is calculated from the sensed d.c.-link voltage Vand the sensed phase current I. The calculated flux-linkage &#x3bb;is compared with a reference flux-linkage &#x3bb;. The reference flux-linkage &#x3bb;corresponds to a reference angle &#x3b8;which lies between angles corresponding to aligned rotor position and non-aligned rotor position in the synchronized reluctance motor. An estimated rotor position &#x3b8;is obtained only once when the calculated flux-linkage &#x3bb;is greater than the reference flux-linkage &#x3bb;.

Method and apparatus for estimating rotor position of switched reluctance motor, and method and apparatus for sensorless control of switched reluctance motor

A structure of a rotor used in a synchronous motor employing both of permanent magnets and a stator using concentrated windings is disclosed. Slits () provided in a section of a rotor laminated in a direction of a rotary shaft are shaped like an arc or a bow, and the shape protrudes toward an outside rim of rotor (). Permanent magnets () are inserted into slits (). This structure produces less magnetic salient poles than a conventional rotor, so that a magnetic flux density can be lowered, and an efficient motor with less loss is obtainable.

Permanent magnet synchronous motor

A motor controller includes a motor-position detector, a motor driver and a power cable having a pair of electric lines (two lines) which feeds power from the driver to the detector. The detector superimposes serial information about the motor-position to the power cable via windings of a transformer or a coupling capacitor. The serial information is obtained by converting parallel information about the motor-position. The serial information superimposed travels to the driver via the power cable. The driver receives the serial information via windings of the transformer or a coupling capacitor, and converts it to parallel information. The driver drives the motor according to this parallel information. The information necessary for driving the motor is superimposed to the power cable and transmitted through the power cable, so that a number of electric lines between the detector and the driver can be minimized.

Motor controller with position detector

An electric motor is equipped with a rotor having multiple rows of slits arranged along a radial direction. A permanent magnet is buried only in some of the slits, namely the ones closest to the center of the rotor or the innermost slits, to drive the motor using both magnet torque and reluctance torque. This improves the torque output.

Electrical motor

A turntable device includes a disc base on the circumference thereof, and the disc base has a hardness more than a given level. The surface of the disc base is roughened at a given level in order to prevent the disc from slipping and adhesion to the disc base. The disc base can compensate surface wobble caused by the disc base. A manufacturing method of the turntable device includes the steps of: a) dripping liquid resin mixed with fine particles on the circumference of the turntable; and b) hardening the resin to form the disc base. The turntable device is good for e.g. CD players, optical disc driving apparatuses.

Turntable device and manufacturing method thereof

A motor controller drives a motor based on signals from commutation sensors (CS signals.) This controller includes (a) a pole position detector for detecting a rotor pole position with edges of the CS signals; (b) a speed detector for detecting a motor speed based on a time interval between the edges of the CS signals; (c) a pole phase detector for estimating a position angle of the rotor based on an output from the position detector and an output from the speed detector; and (d) a phase limiter for restraining the estimated position angle from advancing over a given value. When the limiter continues operating for a certain interval, the controller switches the motor from sine wave driving to rectangular wave driving. This structure allows this controller to drive the motor stably when the motor speed is abruptly changed in the sine wave driving or under field weakening control.

Motor controller

In a motor control apparatus, a current control section (,) controls the motor current by judging whether the current value detected by the current detecting unit (,) is of an overcurrent level exceeding an admissible value (Tmax) or a normal level which is equal to or smaller than the admissible value. When the current value detected by the current detecting unit is of an overcurrent level, the current control section restrains the current value to be supplied to the motor irrespective of the external motor torque or speed command, and when the current value detected by the current detecting unit becomes to be the normal level, the current value to be supplied to the motor is restored to an original non-restraint level.

Current control apparatus with overcurrent protective function for a motor

A motor controller according to the present invention is so configured that time interval measuring means measures the time interval of a rotational position signal indicating the rotational position of a rotor based on said rotational position signal, correction coefficient storage means stores the correction coefficient indicating the inaccuracy of said rotational position signal, estimated rotational angle production means produces an estimated rotational angle providing an estimated value of the rotational angle by extrapolating the rotational angle based on said time interval and said correction coefficient, and command production means produces a current command or a voltage command based on said estimated rotational angle and outputs it to driving means for driving a motor.

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Hyogo, Japan

Taro Kishibe