Abstract: A power converter that interfaces a motor requiring variable voltage/frequency to a supply network providing a nominally fixed voltage/frequency includes a first rectifier/inverter connected to a stator and a second rectifier/inverter. Both rectifier/inverters are interconnected by a dc link and include switching devices. A filter is connected between the second rectifier/inverter and the network. A first controller for the first rectifier/inverter uses a dc link voltage demand signal indicative of a desired dc link voltage to control the switching devices of the first rectifier/inverter. A second controller for the second rectifier/inverter uses a power demand signal indicative of the level of power to be transferred to the dc link from the network through the second rectifier/inverter, and a voltage demand signal indicative of the voltage to be achieved at network terminals of the filter to control the switching devices of the second rectifier/inverter.

Abstract: A motor driving control apparatus includes a motor driving unit which drives a motor and a driving control unit which supplies to the motor driving unit a command value for the motor driving unit to drive the motor. A power characteristic acquiring unit acquires a power characteristic of an AC power supply that supplies power to the motor. A control parameter determining unit determines based on a voltage characteristic of the AC power supply whether, during driving of the motor, the voltage of the AC power supply drops to a level that adversely affects the driving of the motor, and if positive, the control parameter determining unit sets a control parameter so that the voltage of the AC power supply does not drop below that level and supplies the control parameter to the driving control unit in order for the driving control unit to determine the command value.

Abstract: A method for ascertaining measured values in a cyclically controlled system, the cyclic control having control time periods in which the system is controlled, and no-control time periods in which the system is not controlled, having the following operations of determining first integration time periods as a function of the cyclic control, the first integration time periods being situated within at least one of the control time periods, and/or determining second integration time periods as a function of the cyclic control, the second integration time period being situated within at least one of the no-control time periods; detecting one of the measured variables of the system dependent on the control; ascertaining summation and/or integration values by summation and/or integration of the measured variable during the first and/or second integration time periods; ascertaining the measured value for at least one of the control time periods and/or no-control time periods on the basis of time data of the first and/

Abstract: A zero-crossing detection circuit and a commutation device using the zero-crossing detection circuit are provided. The zero-crossing detection circuit is adapted into a three-phase brushless DC (direct current) motor with first to third coils. One terminal of each of the first to third coils is electrically coupled together with each other. The detection circuit comprises a first selection circuit, a second selection circuit and a comparator. The first selection circuit and the second selection circuit are both electrically coupled to another terminals of the first to third coils, to obtain first to third terminal voltages, and output one of the first to third terminal voltages according to a selection signal. The comparator is configured for comparing an output of the first selection circuit and an output of the second selection circuit, to output a comparing result.

Abstract: A load drive control device includes a driver that drives a load which is operable by a DC drive and a pulse modulation drive, a protecting section that detects an electric current flowing in the driver, a temperature detecting section that detects a high temperature state of the driver, and a control section that determines whether the load is operated by the DC drive or the pulse modulation drive, based on outputs from the protecting section and the temperature detecting section. The control section switches the driver in the DC drive and measures the electric current flowing in the driver when a temperature equal to or higher than a predetermined temperature is detected during the pulse modulation drive.

Abstract: A diesel-electric drive system includes a generator having two multi-phase winding systems, a diesel engine, and a DC-link converter. Two self-commuted pulse power converters on the generator side are linked to the windings systems and to each other by a brake resistor on the alternating voltage side. The brake resistor is split into two series-connected resistors, each having half the resistance value of the brake resistor. An input of a bipolar switching device is connected to a connecting point of two series-connected resistors. The capacity of the diesel motor can then be checked in a self-load test with a controllable load torque of the diesel-electric drive system, while eliminating overloads of the power semiconductors of the self-commuted pulse power converters on the generator side.

Abstract: A two-phase BLDC motor comprises a stator and a rotor. The stator has a stator core and a two-phase winding wound on the stator core. The stator core comprises a plurality of teeth with slots formed between adjacent teeth. The rotor rotor has a plurality of magnetic poles formed by at least one permanent magnet. The windings are received in corresponding slots in such a way that each winding spans multiple teeth and the direction of current flowing through the windings in any one slot at any one time is the same.

Abstract: An electric drive machine includes an electric drive system including an internal combustion engine and an electrical power generator coupled to the internal combustion engine. An electronic controller is in control communication with the electric drive system and is configured to determine an estimated temperature of a rotor of the electrical power generator at least in part by determining a rotor temperature rise estimation, compare the estimated rotor temperature to a rotor temperature threshold, and initiate an excessive temperature action if the estimated rotor temperature is greater than or equal to the rotor temperature threshold.

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 device for supplying energy to a long stator winding having multiple winding sections. The device includes an energy source, a supply line connected to the energy source, section switches that are connected to the supply line and that each have a connection for connecting the switch to one winding section each. The device is configured to enable reactive (idle) power compensation independently of the closed-loop control of the energy source. The device for the reactive power compensation is configured to adjust the impedance of the device.

Abstract: A power supply device for a variable rotation speed drive includes a free-running converter connected to a land-based power grid, and an inverter connected to the variable rotation speed drive. A direct-current cable electrically connects the DC side of the converter with the DC side of the inverter. The inverter includes a plurality of phase modules having an upper and a lower valve branches with least two series-connected, two-pole subsystems with distributed energy storage devices. The inverter is located on the seabed in immediate vicinity of the variable rotation speed drive. Signal electronics of the inverter is located on land. In this way, the distance between the power supply on land and the drive on the ocean floor can reach several hundred kilometers, with ocean depths of several kilometers.

Abstract: An overspeed protection subsystem is provided for a power tool having an electric motor. The overspeed protection subsystem is comprised of: a motor switch coupled in series with the motor; a motor control module interfaced with the motor switch to control switching operation of the motor switch; and an overspeed detection module that determines rotational speed of the motor and disables the power tool when the rotational speed of the motor exceeds a threshold.

Abstract: Motor drives and switch driver power systems are presented in which high frequency AC current (IHF) is provided through one or more cables (202) magnetically coupled with local driver current transformers (240), and the transformer secondary currents are converted to provide DC power to switch drivers of an active power converter stage (110a, 110b) in the motor drive.

Abstract: A vibration damping apparatus including reference wave production section that produces a reference wave; a fundamental order adaptive algorithm block that calculates fundamental order adaptive filter factors from a vibration detection signal and the reference wave and produces a fundamental order vibration damping current instruction; an amplitude detection section that calculates a peak current value of the fundamental order vibration damping current instruction; and a fundamental order current excess detection section that derives a fundamental order current upper limit value from the fundamental frequency to produce a fundamental order current upper limit excess signal that is output to the fundamental order adaptive algorithm block, which revises the fundamental order adaptive filter factors in a direction in which the vibration damping current instruction is limited within a range.

Abstract: Power conversion systems with active front end converters for example motor drives and power generation systems for distributed energy sources are presented with adaptive harmonic minimization for grid-tie converters for minimized or reduced total harmonic distortion in the line current spectrum including the source harmonic current and the grid-tie converter injected current spectrum referred to the line side.

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 piezoelectric element drive circuit for outputting a signal that drives a piezoelectric element, the piezoelectric element drive circuit including: a frequency signal generation unit that outputs a frequency signal whose frequency is altered discretely; a voltage-controlled oscillator that alters the frequency of an output signal based on an inputted voltage; a phase comparator that compares the phase of the output signal from the frequency signal generation unit and the phase of the output signal of the voltage-controlled oscillator; and a loop filter that inputs, into the voltage-controlled oscillator, an output voltage that is altered based on alterations in an output signal from the phase comparator. The output signal of the voltage-controlled oscillator is the signal that drives the piezoelectric element.

Abstract: During rain, including a light source (5) for radiating light such that the light is transmitted through a vehicle window (2), a light receiving element (6) for sensing an optical signal when the light radiated from the light source (5) is reflected from the raindrop fallen on the vehicle window (2) and performing a photoelectric transduction, and a receiver (9) for receiving the photoelectrically transduced signal from the light receiving element (6) and judging the level of rainfall. The light source (5) and the light receiving element (6) are inclined with respect to the surface of the vehicle window (2) such that the light of the light source (5) directly reflected from the vehicle window (2) exits to the outside of the light receiving element (6) and the light reflected from a raindrop (8) on the vehicle window (2) is received by the light receiving element (6) to operate a vehicle wiper.

Abstract: First and second A/D converters perform analog/digital conversion of first and second signals of a Hall signal so as to generate third and fourth signals as digital signals. A differential conversion circuit generates a fifth signal as a single-ended signal that corresponds to the difference between the third and fourth signals. An offset correction circuit corrects offset of the fifth signal so as to generate a sixth signal. An amplitude control circuit stabilizes the amplitude of the sixth signal to a predetermined target value, and generates its absolute value, thus generating a seventh signal. A control signal generating unit generates a control signal based upon the seventh signal. A driver circuit drives a motor according to the control signal.

Abstract: In a linear driving device 7, in which a driving shaft 21 vibrates in an axial direction by a vibration member 17, as a result of which a movable body 3 that is frictionally contact with the driving shaft 21 slides along the axial direction of the driving shaft 21, the vibration member 17 includes a piezoelectric element 23 and a vibrator 19 made of a metal plate having elasticity; the vibrator 19 is fixed to the piezoelectric element 23 by superimposing plate faces thereof; the driving shaft 21 has a trunk 25 along which the movable body 3 slides, and an end portion 26 to be fixed to the vibrator 19; a base surface 24 of the end portion 26 abuts with and is fixed to the vibrator 19; and an area of the base surface 24 is smaller than a cross sectional area of the trunk 25.