Abstract: A method for controlling a permanent magnet synchronous motor is disclosed. The method comprises receiving a feedback current from a motor; generating a digital current signal based on the feedback current, the digital current signal indicative of a value of the feedback current; generating a power signal and a first imaginary power signal based on the digital current signal and a three-phase voltage signal; receiving a speed signal indicative of an expected speed of the motor; generating a phase signal based on the speed signal and the power signal; generating a voltage signal based on the speed signal, the power signal, and the first imaginary power signal; and adjusting the three-phase voltage signal for driving the motor based on the voltage signal and the phase signal.

Abstract: A runout measurement system is proposed for measuring the runout of a moving surface of a device having a rotating body, such as a mass storage device (100) (e.g. a hard disk drive) having a rotor which in use includes a rotating recording medium. A sensor (102) interacting with the moving surface obtains a displacement signal. The displacement signal is sampled by a sampling unit (104) controlled by a unit (109) which initiates sampling based on both a signal indicating a ZCP and the clock signal of a high frequency (e.g. 20 MHz) clock (106). Simultaneously, the same clock (106) is used by a counter 108 to measure the spacing between one or more ZCP times. This permits the correspondence between the sampling times and the angular position of the rotor to be found with a high accuracy which depends upon the clock frequency, and thereby allows calculation of repeatable runout (RRO) and non-repeatable runout (NRRO).

Abstract: A surge current protection circuit, has a control unit having an output end, a photoelectric coupling and driving circuit, a silicon symmetrical switch having a control end, and a current-limiting resistor. The current-limiting resistor and the silicon symmetrical switch are parallel connected altogether and then serially connected to a load and an AC input, and the control end of the silicon symmetrical switch is connected to the output end of the control unit via the photoelectric coupling and driving circuit. The invention features low production cost, high reliability and improved power efficiency, and is capable of effectively suppressing surge current.

Abstract: An electric motor control apparatus capable of controlling a motor normally regardless of failures is obtained without increased cost. The apparatus includes a position sensor failure determination unit which outputs a failure determination signal, and generates a first phase; a motor rotation speed calculator which operates based on the failure determination signal and position sensor signals; a phase command generator producing a phase command based on the first phase, the failure determination signal and rotation speed; an amplitude command generator that generates an amplitude command indicating magnitude of a driving signal for the motor, and an electrical energization unit that applies the driving signal to the motor based on the phase command and the amplitude command. Upon failure of a position sensor, the phase command generator generates the phase command using the first phase, and a second phase obtained based on the first phase and the rotation speed.

Abstract: Motors, such as DC motors, and methods and systems for operating a motor, are described. The motor is optionally an electronically commutated motor. The motor comprises one or more electromagnets and a controller device to control the electromagnets. The controller device is configured to calibrate the motor operation in a desired installation to determine the torque needed to achieve a desired operating speed by causing the motor to ramp up to the desired speed, measuring an electric current needed to operate the motor at the desired speed, and setting a value corresponding to a first speed tap using the measured electric current. The controller device is configured to operate the motor in a substantially constant torque mode using the set value at least after the completion of the calibration operation. The motor may be configured for use in a ventilation system, such as an HVACR system.

Abstract: An arrangement for controlling frequency converter modules of an electric drive. In the arrangement, the frequency converter modules are arranged to control alternatively a first motor or several motors having less power than the first motor.

Abstract: Simple AC circuitry driving a brush-less motor having a rotor consisting of alternate polarity permanent magnet poles, with the rotor journaled in a stator with a like number of wound poles having only two free ends for energizing. The motor is using only two AC electronic switches for starting and accelerating, and an AC switch to run the motor at synchronous speed. It has higher efficiency than previously known circuits, uses less parts and is less costly.

Abstract: A self-adjusting door closer is disclosed. The door closer is self powered and includes a control unit to intelligently control a valve within the door closer to vary the operating characteristics of the door closer as needed. The controller includes a position sensor to determine a position of the door, and at least one input switch to enable user selection of at least one door closer parameter for an installed door closer. The control circuitry is operable to set the valve in response to the user selection of the door closer parameters, and the position of the door, in order to control force exerted by the door closer on the door. A generator can be provided to provide electricity to power the controller and store power to operate the controller.

Abstract: An apparatus for driving a motor of an electric vehicle is provided. The apparatus includes a capacitor supplied with power by a battery; an inverter configured to include a plurality of switching elements, convert direct current (DC) power stored in the capacitor into alternating current (AC) power in accordance with the switching of the switching elements and drive a motor with the AC power; and a capacitor protector provided between the battery and the capacitor and configured to consume initial power supplied by the battery at an early stage of the supply of power by the battery, the capacitor protector including a common resistor that consumes the DC power stored in the capacitor when the capacitor is discharged. Therefore, it is possible to guarantee the reliability of the apparatus.

Abstract: A blower motor assembly having a variable speed motor that is suitable for replacing a PSC motor in a residential HVAC (heating, ventilation, and air conditioning) system. The blower motor assembly includes a variable speed motor and motor controller; a first power input for receiving a plurality of AC power signals from a control device for use in determining an operating parameter for the motor; and a second power input for receiving AC power from an AC power source for powering the motor controller even when no AC power signals are received by the first power input.

Abstract: A motor drive for driving two-phase motors using a three-phase bridge output stage, and a method of operating the drive. The driven two-phase motor can be a two-phase bipolar motor (such as a hybrid stepping motor). The drive can also be configured so that a single output stage can be used to drive either two-phase or three-phase motors, with or without a feedback sensor. A reference return is provided from one of the three half-bridge output stages with each of the motor phase windings connected between the reference return and one of the other half-bridge outputs. The switches of each half-bridge are modulated so that current can be controlled in each of the two motor phase windings.

Abstract: A drive signal generating unit generates a drive signal used to alternately deliver a positive current and a negative current to a coil. The drive signal is such that nonconducting periods are set before and after a positive current conducting period and the nonconducting periods are set before and after a negative current conducting period. A driver unit generates the drive current in response to the drive signal generated by the drive signal generating unit and then supplies the drive current to the coil. The drive signal generating unit sets the width of a nonconducting period such that, after the drive start of the linear vibration motor, the width of a nonconducting period to be set before at least the first conducting period of the drive signal is shorter than the width of a nonconducting period to be set before each conducting period during steady operation of the linear vibration motor.

Abstract: Disclosed is a linear scale for obtaining a distance from a reference point. A scale detection mechanism is adapted to output waveform signals of the same phase. Also the scale detection mechanism corresponds to a magnetic flux density generated by magnetic bodies of a scale element. The scale detection mechanism may be sensors. The sensors are arranged at even intervals corresponding to a scale length of the scale element. The sensors are adapted to output sine-wave signals having the same phase to continuously detect the scale element in a movement direction of the scale element. The scale element has opposite ends each has the same polarity and configured such that an output voltage of the single sensor detecting the end of the scale element is reduced to one-half of an output voltage of the single sensor detecting the remaining portion of the scale element.

Abstract: A refrigerator and a method for controlling the same are provided. With the refrigerator and the method for controlling the refrigerator, a receiving box may be automatically drawn in and out together with a door when a user operates an input device that inputs door drawing in and out instructions, thereby increasing use convenience of children and older people.

Abstract: A method of controlling an electrical machine that includes commutating a phase winding of the electrical machine at a time T_COM(1) after a first edge and at a time T_COM(2) after a second edge of a rotor-position signal. T_COM(2) is defined by the equation: T_COM(2)=T_COM(1)+T_AVE?T_PD, where T_AVE is an average period between edges of the rotor-position signal, and T_PD is the period between the first and second edges. Additionally, a controller and control system that implement the method.

Abstract: A pulse width modulation (PWM) module is configured to adjust the input PWM control signal and the motor can be implemented in different rotation speed to enhance the flexibility of the implementation of the motor when the PWM control signals are the same. In addition, the PWM modulation block in the present invention includes a PWM direction control circuit, a PWM vector transfer circuit and a PWM signal generation circuit. Apparently, the PWM modulation block of the present invention is connected to a PWM control signal inputted by an external system and an external adjustment apparatus; by setting up the adjustment apparatus, the vector and the modulation direction of the PWM control signal can be adjusted, and the duty cycle of the PWM control signal can also be adjusted.

Abstract: A refrigerator and a method for controlling the same are provided. In this refrigerator and control method, a receiving box may be automatically drawn in and out together with a door based on a movement command received at an input unit, thus enhancing user convenience and satisfaction.

Abstract: A motor controlling apparatus includes a control unit which sets a motor on standby for a predetermined time if an enable signal is applied and sets the motor to a default state by rotating the motor at least once for the next predetermined time. The apparatus includes a driver unit which generates a drive signal to control the motor and outputs the drive signal to the motor. Accordingly, a stepping out of the motor may be prevented.

Abstract: A motion control system including components such as an accelerometer for detecting zero force positions and for self-calibrating the motion control system. The motion control system may be implemented in an active seat suspension.

Abstract: The encoder includes a disk in a disk shape that is arranged rotatably about a rotation axis and that includes one track in a ring shape on which a rotating grating is formed and one or more origin detection areas serving as partial areas on which a rotating grating is formed, and a mask that is fixed and arranged in a manner facing the disk and on which one or more fixed gratings are formed so as to constitute a diffraction interference optical system together with the rotating gratings. A plurality of slits and included in at least one rotating grating are formed along a curved line obtained by curving a plurality of radial lines about the rotation axis in the circumferential direction at predetermined curvature such that pitches and of the slits and can be set to a predetermined value.