Abstract: Embodiments of the invention provide a way to accurately detect the position of a spindle motor. In a spindle motor startup process according to one embodiment, a parameter setup section acquires from a parameter table a sense time value corresponding to an input voltage that is acquired from an ADC. The parameter setup section sets the sense time value in a register. A position determination section, which is within an SPM driver, performs an induced voltage detection process for rotor position detection purposes during the time corresponding to the sense time value that is set in the register. Even when the input voltage is decreased, rotor position detection can be properly achieved by changing the sense time value in accordance with a change in the input voltage.

Abstract: A method of and system for identifying the position of magnetic poles of a rotor of a multi-phase electrical machine relative to a stator of that machine is disclosed. The method includes the steps of applying a voltage pulse to stator windings of each phase, sensing current flow in the stator windings of each phase due to the application of the voltage pulse to the respective stator windings and determining the position of the magnetic poles of the rotor relative to the stator using the sensed current flow in the stator windings of each phase. The method is characterized in that the phases of the stator windings are star-connected at a neutral junction and the voltage pulse is applied to the stator windings of each phase in parallel.

Abstract: A system and method for reducing fan noise by controlling the drive current to the fan motor. In one embodiment the system approximates a linear drive using a number of transistors in parallel and sequentially deploying the transistors. In another embodiment, a scheme is used to activate and deactivate transistors in discrete steps thereby achieving the benefits of the linear controller topology.

Abstract: In response to detection of a skid of drive wheels based on an increase in angular acceleration ? of a rotating shaft of a motor, the control procedure of the invention refers to a map representing a variation in maximum torque Tmax against the angular acceleration ? and sets torque restriction of the motor to limit the torque level of the motor to the maximum torque Tmax corresponding to a peak value of the angular acceleration ?. When the torque restriction sufficiently lowers the angular acceleration ? to detect convergence of the skid, the control procedure cancels the torque restriction to a certain level of the maximum torque Tmax corresponding to a torque restoration limit ?1, which is set according to the degree of the skid. The torque restoration limit ?1 (that is, the maximum torque Tmax) is cancelled in a stepwise manner by a cancellation rate and a cancellation time corresponding to an additional accelerator depression relative to an accelerator opening at the time of detection of the skid.

Abstract: A vehicular generator-motor 1 is composed of a rotor, a stator having three phase armature winding 2, and a converter 4. The rotor is provided with a field winding 3 for magnetizing a plurality of magnetic pole pieces 14a, 15a, and permanent magnets 17 for magnetizing the magnetic pole pieces 14a, 15a together with the field winding 3. When the generator-motor 1 is operated as a motor, the converter 4 is operated as an inverter to restrain the armature current at the time of low speed rotation to the extent of the additional magnetic flux from the permanent magnets.

Abstract: A position controller of a motor in which the position time can be shortened even if an external force is applied. A speed control unit (13) comprises a compensation low-pass filter (133) having a transfer function corresponding to a delay of a speed control system. The speed control unit (13) further comprises an integral control system including a speed integrator (132) for integrating the difference between a speed and a delay speed command to the low-pass filter (133) compensating the delay in the speed control unit. A proportional control system outputting a command proportional to the speed command, and a multiplying means (134) for multiplying the sum of outputs from the integral control system and the proportional control system by a speed proportional gain and outputting the result as a torque command.

Abstract: The invention is directed to controlling an electric motor by means of a frequency converter. The frequency converter can be connected to one of several different mains voltages. According to the present invention, the maximum output power of the frequency converter, is limited when the actual mains voltage is lower than the maximum nominal mains voltage, for which the frequency converter is designed, and during the limitation the frequency converter controls the speed of the motor within a power range up to a limited maximum output power. This gives a genuine multi-voltage unit, which can be connected to a wide range of mains voltages.

Abstract: An electronic circuit for starting a single phase induction motor, of the type containing a rotor and a stator with at least one running coil (B1) and one starting coil (B2), for operating jointly with an alternating current source (F), comprising: a trigger electronic switch; a trigger circuit (TR) of said trigger electronic switch; and a blocking circuit (BL) for controlling the trigger pulses of the trigger electronic switch, said blocking circuit (BL) sustaining its blocking state while there is voltage being induced to the coils of the motor (M) by rotation of the rotor, maintaining said blocking state for a certain time after said induced voltage has been substantially reduced.

Abstract: A driving apparatus for moving an object. The apparatus includes a first actuator which drives the object in X and Y directions, a second actuator which drives a reaction force counter which receives a reaction force generated when the first actuator drives the object, and a controller which controls the second actuator on the basis of X- and Y-direction positions of the object and X- and Y-direction accelerations of the object so as to cancel, by the second actuator, the reaction force to be received by the reaction force counter when the object is driven by the first actuator.

Abstract: A motor drive circuit includes a first transistor. The collector of a second transistor is connected to the emitter of the first transistor in series. A motor is connected to a connection point between the first and second transistors. A first brake control circuit turns off the first transistor and turns on the second transistor in accordance with a brake operation instruction signal. A second brake control circuit forces the first transistor to be turned OFF in accordance with the brake operation instruction signal independently from the first brake control circuit.

Abstract: A method of the invention is for controlling a DC printer motor with a motor driver during a potential stall of the DC printer motor. One step of the method includes detecting the start of the potential stall of the DC printer motor. Another step includes thereafter during the potential stall using an input to the motor driver which corresponds to a pulsed desired motor voltage. A further step includes outputting from the motor driver a control voltage to the DC printer motor based on the input. In one example of the method, the start of a potential stall of a DC printer motor is detected at least one time when a printhead carrier moved by a DC printer motor of an inkjet printer encounters a capping device of the inkjet printer while returning to the printer sidewall home position of the printhead carrier.

Abstract: In a method for measuring motor speed and position by detecting the back EMF generated during pole-pair interactions, a separate respective duration of a power phase suppression signal, that is set during back EMF detection, is stored in memory for each respective pole. The separate respective duration values are determined during a calibration phase by iteratively lengthening each respective duration one unit at a time (up to a maximum value) until no part of the respective back EMF signal occurs outside the suppression signal duration, and those values are stored. During operation, the approach of a pole-pair interaction may be determined from the electrical cycle of the power supply, and then the stored duration value is used to control the state of the suppression signal.

Abstract: A barrier movement operator which uses an A.C. motor to move a barrier is disclosed herein. The operator senses a characteristic of barrier movement, such as motor rotation speed, to detect when the barrier contacts an obstruction. The motor and/or the circuitry for applying electrical power to the motor have been enhanced to improve the detectibility of contact with an obstruction.

Abstract: A synchronous control device which is provided with drive motors and a central control unit generating a synchronous reference signal and with which the drive motor is controlled to rotate synchronously with the synchronous reference signal supplied from the central control unit, which is provided with: device motor brakes for braking a rotation of the drive motor; machine home position detectors for detecting a rotation phase of the drive motor; and drive controlling means for controlling a drive motor in such a manner that the drive braking means is activated depending on a stop instruction supplied from the central control unit and a required rotation phase of the drive motor is stored; a comparison between the required rotation phase of the drive motor and the rotation phase thereof is performed at the time of re-start; and a home position alignment of the drive motor is performed at a start time of a subsequent operation.

Abstract: It is disclosed the motor stop control device having the stepping motor 49 as the drive source of the reel 3 on which a plurality of symbols are formed, the motor stop control device being utilized in the reel-type gaming machine 1 and stopping the stepping motor 49 corresponding to the stop instruction from an external. When the stop instruction of the stepping motor 49 occurs based on the instruction from an external, the main CPU 31 drops the voltage value added to the stepping motor which is rotating at the constant speed to the voltage value lower than such voltage value and executes the stop process of the stepping motor 49 by 2-phase excitation.

Abstract: It is an object of the invention to provide a method which can detect a magnetic pole position easily and surely by using high-frequency currents such as harmonics of an inverter output and carrier frequency components. The invention provides a method of detecting a magnetic pole position of a motor and an apparatus for detecting a magnetic pole position in which, although high-frequency currents of carrier frequency components or the like are used, a special current detecting circuit is not required, and synchronization between the current detection timing and the position calculation can be easily attained, and also to provide an apparatus for controlling a motor using the same.

Abstract: An AC servo drive without current sensor includes a PI (proportional integration) controller, at least two first-order controllers (polar point and zero point), a decoupling compensator, a coordinate converter, a pulse width modulator, a counter and a speed estimator. The AC servo drive is connected with a servomotor to form an AC servo module. The servomotor comprises an encoder receiving a current command signal from the servo module to function as input current command signal or the d, q axes PI controller and the decoupling compensator. The voltage command signal generated by the d, q axes PI controller and the signal generated by the decoupling compensator form a control signal and input to the coordinate converter. The signal output from the coordinate converter is processed by PWM controller to control the servomotor. Therefore, the deterioration of servo motor control caused by temperature drift and cost can be solved.

Abstract: There is provided a synchronous control device for driving the same control object with two servomotors. The synchronous control device detects the physical quantity that represents the difference between the forces on the two servomotors, and, on the basis of the detected value, reduces the force that acts between the two servomotors.

Abstract: A control apparatus for an electric railcar that provides control so that when rotational speed of a motor decreases below a required value, torque of the motor will decrease at a required rate of change, a current limiter for limiting a torque current command “(A)Iqp” output from a current command arithmetic unit is provided to ensure that when the rotational speed of the motor decreases below the required value, the torque current command will be limited to a command value “(B)Iqp” smaller than that command value, and to ensure that a carrier frequency at which PWM signals are created when switching elements of the electric power converter are controlled by carrier generator is controlled to become lower than a carrier frequency existing when the rotational speed of the motor decreases below the required value.

Abstract: Latch control methods and systems are disclosed, including a latch that receives power from a motor associated with a latch. A sensor can be provided for monitoring the current consumption of the motor. A microcontroller can control the latch and/or the motor, based on the current consumption data received from the sensor concerning the current consumption of the motor. Monitoring of the current waveform of the motor therefore provides speed and direction feedback data for control of the latch. Additionally, a microprocessor can process instructions for controlling the interaction of the motor, the latch, the sensor and/or the microcontroller. Such a current monitoring control system is made possible by variation in current consumption of the motor during rotation as a result of commutation, which can be interrogated by measuring the voltage drop across the motor or a shunt resistor, or through the use of other current sensors, such as, for example, a Hall-effect type current sensor.