Abstract: In a control device for discharging a DC link capacitor by means of a discharging device including a load resistor and a switch element connected in series with the load resistor, the control device includes a generator unit, which is configured to generate a pulse width-modulated actuation signal for the switch element with an ascertained duty cycle, and a control unit, which is configured to ascertain the duty cycle in such a way that, in the time average, a desired discharge current flows through the load resistor.

Abstract: A motor driving apparatus which drives a motor including a plurality of windings corresponding to a plurality of phases, respectively, includes: a first inverter including a plurality of first switching elements and connected to a first end of each of the windings; a second inverter including a plurality of second switching elements and connected to a second end of each of the windings; and a controller obtaining a vector corresponding to a voltage command of the motor by combining switching vectors which cause difference between a common mode voltage of the first inverter and a common mode voltage of the second inverter to be zero and configured to control the plurality of first switching elements and the plurality of second switching elements in a pulse width modulation method based on the obtained vector.

Abstract: Method of controlling a multi-level inverter having inputs connected to a gate drive unit controlling the inverter and an output connected to a load, the multi-level inverter capable of generating a PWM voltage signal having three or more modulation levels, the inverter powered by a voltage supply and comprising at least one neutral point (NP), the method comprising operating the multi-level inverter in a standard modulation pattern having three or more modulation levels when one or more parameters representative of neutral point stability each have a value within a first range indicative of a high neutral point stability, and operating the multi-level inverter with a two-level modulation pattern when said one or more parameters representative of neutral point stability each have a value within a second range indicative of a low neutral point stability, the first range separated from the second range by a threshold value.

Abstract: The present disclosure relates to a motor driver and a method of driving a motor capable of driving a motor with optimum efficiency. The method of driving the brushless direct current (BLDC) motor may include an initial driving operation, a test operation of adjusting a turn-on time and a transition time in the test mode step by step, driving the BLDC motor by applying the adjusted turn-on time and the adjusted transition time, and detecting a driving error of the BLDC motor, an operation of repeating the test operation when the driving error is not detected in the test operation, and an operation of setting the turn-on time and the transition time, which are adjusted in an operation just before the driving error is detected, as a turn-on time and a transition time in an optimum driving mode.

Abstract: A control device includes: an angular velocity detection unit that detects an angular velocity of a motor; a vibration component removal unit that removes a vibration component in a predetermined band from the angular velocity detected by the angular velocity detection unit by filtering; and a current command calculation unit that calculates a current command value of a drive current for driving the motor according to a torque command value and the angular velocity from which the vibration component has been removed by the vibration component removal unit.

Abstract: A linear electric actuator system, preferably for patient lifters, comprising at least one linear electric actuator and a controller having a power limiting circuit for limiting the power to the at least one linear electric actuator. The actuator system is arranged such that the threshold value of the maximum permissible power in the power limiting circuit may be changed, and that this change may be performed via reference to the position of the spindle nut on the spindle as a look up in a table showing a corresponding value for the power limit.

Abstract: A first torque estimator determines a first torque estimation value according to a cross product method, and a second torque estimator determines a second torque estimation value according to an energy method. A torque weight adjuster adjusts, using a weighting coefficient calculated in accordance with a predetermined condition, weightings respectively applied to these two types of torque estimation values, and outputs a torque estimation value.

Abstract: A motor driving device for driving a motor having multiple windings corresponding to multiple phases, respectively, may include: a first inverter including multiple first switching elements and connected to a first end of each of the multiple windings; a second inverter including multiple second switching elements and connected a second end of each of the multiple windings; a third switching element configured to connect/disconnect points, at which the number of turns of each of the multiple windings is partitioned based on a predetermined ratio, to/from each other; and a controller configured to control, based on the required output of the motor, an on/off state of the first switching elements to the third switching element.

Abstract: An electric motor control device, capable of suppressing a torque ripple even when electrical characteristics on a motor have errors or variations, comprises: a fundamental electric-current instruction generator for outputting d-axis and q-axis fundamental electric-current instructions for outputting fundamental torque from the motor having saliency; a position dependency component generator for outputting a position dependency component(s) of the motor according to its rotational position; an electric current correction instruction calculator for calculating d-axis and q-axis current correction instructions from the d-axis and q-axis fundamental electric-current instructions, and the position dependency component(s); an electric current correction instruction superposition unit for generating d-axis and q-axis current instructions by performing superposition of the d-axis and q-axis current correction instructions on the d-axis and q-axis fundamental electric-current instructions; and an electric current con

Abstract: An assist mechanism includes: an electric motor; a shaft-shaped member in which a worm engaged with a worm wheel is formed; and a coupling that couples an output shaft of the electric motor and the shaft-shaped member to each other. The smallest rotation order among rotation orders of the electric motor and a rotation order of the worm are prime to each other. The smallest rotation order among the rotation orders of the electric motor and a rotation order of the coupling are prime to each other. The rotation order of the worm and the rotation order of the coupling are prime to each other. The rotation order of the worm is 3. The rotation order of the coupling is 5 or 7.

Abstract: In some examples, an apparatus operable to drive a motor includes driver circuitry adapted to be coupled to the motor and processing logic coupled to the driver circuitry. The processing logic is operable to determine an expected current for controlling the motor, reduce a reference current upon which the motor is controlled from a first value to a second value at an exponential rate, determine that a measured current of the motor is approximately equal to the expected current, and responsive to determining that the measured current of the motor is approximately equal to the expected current, provide a control signal to the driver circuitry based on the expected current to the motor to control the motor to operate according to closed loop control.

Abstract: Described is a method of determining an initial speed of a synchronous motor having a permanent magnet rotor. The method comprises controlling said motor to cause the rotor to rotate or observing that the rotor is rotating. The method includes sensing stator winding currents and transforming the sensed stator winding currents into a two-dimensional (2D) coordinate system using an alpha-beta (?-?) transformation. The rotor angle ? is determined from an arc tangent (Atan) of the ratio of the current in the ?-axis to the current in the ?-axis. The initial motor speed ? is determined from the determined rotor angle ?.

Abstract: Provided is a control device for a rotating electric machine, the control device being configured to control an inverter configured to apply a voltage to each phase winding of a rotating electric machine, to thereby control, for the each phase winding, a current to be supplied to the each phase winding, the control device including a control unit configured to: calculate a voltage command value to be applied to the each phase winding so that a phase difference between harmonic components of the same order in a radial magnetic flux density and a circumferential magnetic flux density of an air gap portion between a stator core and a rotor core of the rotating electric machine becomes a phase difference target value determined in advance, and to control the inverter in accordance with the calculated voltage command value.

Abstract: A motor current protecting circuit is provided. A voltage calculating circuit determines whether or not each of low-side switches is fully turned on and then determines whether or not a voltage difference between a first terminal and a second terminal of each of the low-side switches being fully turned on is larger than or equal to a zero value. The voltage calculating circuit adds up the voltage differences each of which is larger than or equal to the zero value to output a voltage signal. A control circuit controls a driver circuit to switch the low-side switches and high-side switches according to the voltage signal.

Abstract: A multi-phase permanent magnet rotor motor comprises a plurality of phase coil windings with each phase coil winding having two free ends and the plurality of phase coil windings being without a common node. A controller is provided comprising a plurality of full-bridge inverters. Each full-bridge inverter has two output ends electrically connected to the two free ends of a corresponding phase coil winding. The controller is configured to operate the plurality of full-bridge inverters to output pulse modulated control signals to their respective phase coil windings. The outputted pulse modulated control signals can comprise a combination of sine wave signals and full-bridge space vector modulation signals.

Abstract: A motor drive system includes motor drive control devices supplying first and second powers to first and second coils, respectively. The first motor drive control device includes: a detector communication unit acquiring a mover movement detection value; a position and speed control unit generating a thrust command to cause the movement detection value to follow a time-series movement target value received from an external device; and a current control unit supplying, to the first coils, the first power to cause thrust generated on the mover to follow the thrust command, and generating data on third power to be supplied to the second coils and transmitting the data to the second motor drive control device when the mover moves from the first coil to the second coil. The second motor drive control device supplies the second power calculated using the data on the third power to the second coils.

Abstract: A motor driver having an automatic phase switching mechanism is provided. After a three-phase motor is started up, a back electromotive force detecting circuit starts detecting a back electromotive force signal of each of three phases of the three-phase motor. A driving waveform generating circuit extracts parts of a plurality of first wave segment patterns from a first wave segment pattern signal as a plurality of first wave segments of a first waveform signal according to the back electromotive force signal. A motor controlling circuit controls the motor driving circuit to drive the three-phase motor to rotate normally according to the first waveform signal.

Abstract: A motor driving apparatus that drives a motor including a plurality of windings respectively corresponding to a plurality of phases, may include a first inverter including a plurality of first switching elements, and connected to a first end of each of the windings; a second inverter including a plurality of second switching elements, and connected to a second end of each of the windings; and a controller including a current controller to produce, based on a predetermined current command of the motor, a voltage command for determining a switching duty of the first switching elements and the second switching elements, wherein the current controller is configured to produce a zero-phase component voltage command among the voltage commands by applying 3rd harmonic feedforward compensation.

Abstract: To provide a controller for AC rotary electric machine and an electric power steering apparatus which can superimposes a cancellation current for canceling the torque ripple component on the winding current in feedforward manner and cancel the torque ripple component. A controller for AC rotary electric machine calculates an oscillation voltage command value of q-axis which has the same frequency as the torque ripple component; calculates a reverse phase of the torque ripple component based on the current information and the magnetic pole position; calculates a correction phase corresponding to the phase delay of the actual current with respect to the oscillation voltage command value of q-axis; and sets a phase of the oscillation voltage command value of q-axis to a phase obtained by advancing the reverse phase of the torque ripple component by the correction phase.

Abstract: A motor driving apparatus of driving a motor including a plurality of windings respectively corresponding to a plurality of phases is disclosed The motor driving apparatus includes a first inverter including a plurality of first switching elements and connected to a first end of each of the windings, a second inverter including a plurality of second switching elements and connected to a second end of each of the windings, and a controller connected to the first switching elements and the second switching elements and configured to determine an effective vector closest to a voltage vector corresponding to a preset voltage command of the motor as a duty of the plurality of second switching elements and to control pulse width modulation of the first switching elements using a value obtained by adding the effective vector corresponding to the duty of the second switching elements to the voltage command of the motor as a voltage command of the first inverter.