Abstract: A device for controlling an alternating-current motor includes a resolver for detecting a rotational position of an alternating-current motor; and a rectangular wave voltage control unit for performing control based on an output of the resolver to provide a rectangular wave voltage to each phase of the alternating-current motor. The control unit causes an amount of change ?? in a voltage phase of the rectangular wave voltage of each phase from a switching reference phase of each phase to increase or decrease equally for each switching in one cycle of an electrical angle determined based on the output of the resolver. In this way, a device for controlling an alternating-current motor is provided to restrain occurrence of an offset current upon rectangular wave voltage control.

Abstract: Embodiments of the invention comprise a multi-input range box driven by multiple electric drives. Range shifting involves momentarily increasing the current through all but a given motor, to a level that will carry the entire load, comprising specified constant power. Simultaneously, torque of the given motor is reduced to zero. The given motor is then disconnected from supplying power, is synchronized to the input speed of the new speed range, and is then engaged for the new range. The above sequence is then repeated for each remaining motors, in turn. The motor current is re-equalized for all of the motors, after all the motors have been connected to provide power at the new range. Thus, there is no interruption in power flow during a range shift, and the motors are always used to deliver power, rather than to serve as a brake.

Abstract: A method for operating a synchronous motor wherein a magnetic field is generated by a first motor component in a predetermined orientation, the method including generating a relative movement between the first and a second motor component limited to a predetermined value, and determining a direction of the relative movement, wherein the generating and determining are repeated until a change in the direction of the relative movement occurs, wherein a magnetic field having a changed orientation with regard to a previously generated magnetic field is generated by the first motor component, and wherein the orientation of the magnetic field with the changed orientation is changed by a predetermined orientation section and depending on the determined direction of the relative movement. The invention encompasses an amplifier for operating a synchronous motor and a system including an amplifier and a synchronous motor.

Abstract: A shift register which receives a transmission clock signal, which is shifted according to the transmission clock signal, and which outputs a gate signal a predetermined time after reset; a reset circuit which outputs a reset signal for resetting the shift register when the reset circuit receives an input of a step signal for driving the stepping motor; and a switching element which receives the gate signal of the shift register and which is switched between a blocked state and a conductive state are provided in a driving circuit of a stepping motor.

Abstract: Provided is an energy harvesting electric device capable of increasing output power. The energy harvesting electric device includes an energy harvester array including a plurality of energy harvesters, a single rectifier connected to the energy harvester array, and an output unit which is connected to the single rectifier and has a load resistance. The energy harvesters include a plurality of first energy harvesters connected to each other in parallel and a single second energy harvester connected in parallel to the first energy harvesters. The first energy harvesters have a first specific resistance higher than the load resistance and the second energy harvester has a second specific resistance higher than the first specific resistance.

Abstract: The present invention advantageously provides methods for manually and/or remotely controlling a motorized roller shade that includes a shade attached to a shade tube, a DC gear motor disposed within the shade tube and a microcontroller. One method includes detecting a manual movement of the shade using a sensor, determining a displacement associated with the manual movement, and, if the displacement is less than a maximum displacement, moving the shade to a different position by energizing the DC gear motor to rotate the shade tube. Another method includes receiving a command from a remote control, and moving the shade to a position associated with the command by energizing the DC gear motor to rotate the shade tube.

Abstract: This invention provides a device and method for detecting a type of a fan. The device for detecting a type of a fan includes a detector and a voltage controller. The detector is used for detecting and comparing a control voltage with a reference voltage to generate a comparison signal and transmitting the comparison signal to the voltage controller. The voltage controller outputs a variable voltage or a constant voltage to a voltage input terminal of a fan according to the comparison signal. The voltage controller can include an integrator for integrating a modulation signal and outputting the variable voltage.

Abstract: A refrigerator and a method of operating the same are disclosed. In the refrigerator and the method of operating the same, a voltage of an electric power input is measured and rectified through the half wave rectification or the full wave rectification in correspondence with the measured voltage, so that the refrigerator can be used without a voltage converting device when a voltage of the input power is changed. Therefore, the change or the modification of the circuit is not needed in order to use the refrigerator in other regions. Since components are compatible and utility of the components is improved, manufacturing costs can be reduced.

Abstract: An apparatus for generating electromagnetic torque in an N-phase electric machine, N being a positive integer, includes N lines, each of the N lines including an input terminal, an output terminal, and a pair of thyristors, or of one thyristor and one diode pair. The N lines are connected between a mains and the electric machine. An apparatus is provided for repeatedly or continuously determining at least the sign of a voltage over the thyristor or diode-thyristor pair in at least one of the N lines, means are provided for repeatedly or continuously determining at least one parameter related to the electromagnetic field in the electric machine, and a control device is provided for controlling the operation of the thyristor or diode-thyristor pair of the at least one of the N lines.

Abstract: An HVAC unit includes a transformer and a system controller. The transformer is configured to receive power from a first and a second phase of a three-phase power source and to produce a first reduced-voltage waveform therefrom. The system controller is adapted to sample the reduced voltage waveform to determine a figure of merit of the three-phase power source. The controller is further configured to operate the HVAC unit in response to the figure of merit.

Abstract: A motor control device of the present invention includes: target electric current value setting units (15 and 16) that set target electric current values that should be supplied to a motor (1), basic voltage value computing units (511, 521, 51a, and 52a) that compute basic voltage values for driving the motor, a rotation angle speed computing unit (23) that computes a rotation angle speed of the motor, correction value computing units (50, 512, 515, 516, 522, 525, and 526) that compute correction values for correcting the basic voltage values based on motor electric current values and a rotation angle speed of the motor, correcting units (513 and 523) that obtain voltage command values by correcting the basic voltage values by the correction values computed by the correction value computing units, and a driving unit (13) that drives the motor by using voltage command values.

Abstract: A head up display device for a vehicle includes a display; an optical system having a reflecting mirror; a stepping motor; and a control system having a determining device, a micro-step control device, and a forcible control device. The determining device determines whether an adjustment command for micro-step control is given. The micro-step control device performs the micro-step control as long as the determining device determines that the command for the micro-step control is given. The forcible control device forcibly controls a drive signal such that an electrical angle changes to a stabilizing point. When determination made by the determining device switches from determination that the command is given to determination that the command is not given, the forcible control device forcibly controls the drive signal, provided that the electrical angle as of the time of the determination that the command is not given is shifted from the stabilizing point.

Abstract: The invention relates to a variable speed drive comprising a direct-current power bus having a positive line (16) and a negative line (17), and an inverter module (14) supplied by the direct-current bus in order to supply a variable voltage to an electric load (M). The drive comprises an energy-recovery device (10) comprising a first direct-current/direct-current converter (20), the output stage of the first converter (20) being connected in series to the positive line of the direct-current bus, a second direct-current/direct-current converter (30), the input stage of the second converter (30) being connected between the positive line and the negative line of the direct-current bus, and an electric energy storage module (Cs) connected in parallel with the input stage of the first converter (20) and with the output stage of the second converter (30).

Abstract: A method of confining a robot in a work space includes providing a portable barrier signal transmitting device including a primary emitter emitting a confinement beam primarily along an axis defining a directed barrier. A mobile robot including a detector, a drive motor and a control unit controlling the drive motor is caused to avoid the directed barrier upon detection by the detector on the robot. The detector on the robot has an omnidirectional field of view parallel to the plane of movement of the robot. The detector receives confinement light beams substantially in a plane at the height of the field of view while blocking or rejecting confinement light beams substantially above or substantially below the plane at the height of the field of view.

Abstract: A motor control system for heating, ventilation, and air conditioning (HVAC) applications is described. The motor control system includes a thermostat and an electronically commutated motor (ECM) coupled to the thermostat. The ECM is configured to retrofit an existing non-ECM electric motor included in an HVAC application and to operate in one of a plurality of HVAC modes. The HVAC modes include at least one of a heating mode, a cooling mode, and a continuous fan mode. The HVAC mode is determined based at least partially on outputs provided by the thermostat.

Abstract: A frequency converter and a method for determining the position of the rotor of an electric machine are provided. The frequency converter includes a load bridge and a control of the load bridge, for supplying electricity between the load bridge and an electric machine connected to the load bridge. The frequency converter includes a determination for at least one electrical parameter of the electric machine, and includes a determination for the position of the rotor of the electric machine. The load bridge is fitted to supply a first alternating electricity excitation signal, which is formed in relation to the electrical angle of the electric machine, to the electric machine. The frequency converter is further fitted to determine the first alternating electricity response signal corresponding to the first alternating electricity excitation signal, and the position of the rotor is determined on the basis of the first alternating electricity response signal.

Abstract: A battery powered raise climber system is provided that uses Lithium ion batteries to drive a single or double electric drive for an existing raise climber. The batteries offer a faster, safer, quieter and cleaner way to move workers and their equipment to and from the work face in a raise and eliminates the need for adding lengths of hose as the raise climber ascends and eliminates the emission of harmful inhalants. The battery powered system also enables high efficiency area lighting to be used at the work face, and as the raise climber descends in the raise, the electric drives can reverse operation to recharge the batteries.

Abstract: The motor drive circuit 100 supplies a drive current to the motor 2 to drive the motor. Each of the first Hall amplifier HAMP1 to the third Hall amplifier HAMP3 is provided for each phase of the motor 2 and receives a pair of Hall signals from a corresponding phase Hall element to generate each phase sine wave voltage SIN_U, SIN_V and SIN_W by amplifying a difference between the pair of Hall signals. Each of the first PWM comparator PCMP1 to the third PWM comparator PCMP3 is provided for each phase of the motor 2 and compares the corresponding phase sine wave voltage SIN_U, SIN_V and SIN_W, with the periodic voltage Vosc to generate each phase PWM signal PWM_U, PWM_V and PWM_W. The drive unit 10 subjects a phase coil, a target to be driven, to pulse drive by using the pulse modulated signal from the corresponding PWM comparator.

Abstract: A motor drive system includes: a three-phase motor; a power conversion device that supplies power for driving the three-phase motor; and an output filter that is arranged between an output of the power conversion device and the three-phase motor and has a configuration in which a setting value of a filter resonance frequency is selectable and changeable.

Abstract: In one embodiment, an apparatus includes a first member that supports a magnetic flux carrying member and a second member that supports a magnetic flux generating member disposed for movement relative to the first member. An air gap control system is coupled to at least one of the first member or the second member and includes an air gap control device that is separate from a primary magnetic flux circuit formed between the first member and the second member. The air gap control device is configured to exert a force on one of the first and second members in response to movement of the other of the first and second members in a direction that reduces a distance between the first and second members to maintain a minimum distance between the first and second members and/or substantially center the one of the first and second members within the other.