A method for detecting an obstacle opposing the movement of a screen in a home automation closure or sun protection system includes an electromechanical actuator driving movement of the screen. The electromechanical actuator includes a torque support, a housing, an output shaft, and an electric motor including a stator and a rotor. The system includes a winding shaft rotating the screen and a connecting accessory between the electromechanical actuator's output shaft and the winding shaft. The method includes: determining an angular displacement value of the rotor with respect to the stator; determining angular displacement of the winding shaft relative to the housing or torque support of the electromechanical actuator; determining angular deformation of the kinematic chain between the electric motor and the winding shaft by comparing these two angular displacements; and determining the presence of an obstacle to screen movement from an angular deformation exceeding a predefined value.

A method and apparatus for self-commissioning a bearingless-motor drive, which includes a bearingless motor and a control unit of the bearingless motor are disclosed. The motor includes at least one winding and at least one permanent magnet. The method includes generating a magnetic model, the magnetic model including a plurality of constant parameters; supplying, while the movable part remains standstill, to the at least one winding at least two unequal currents; measuring, with a magnetic sensor, flux linkages caused by said at least two unequal currents, respectively; calculating, with the magnetic model, flux linkages by inputting to the magnetic model current values equal to the currents supplied to the at least one winding; and fitting, with a least-squares fitting algorithm, at least one constant parameter in the magnetic model such that the difference between the measured and calculated flux linkages will be minimized.

A power conversion device includes a switching circuitry configured to supply a driving alternating current (AC) power to a motor of a controlled object that includes the motor and a movable part driven by the motor, and detect an abnormality in the controlled object based on the index information acquired.

A system and computer-implemented method for reducing an angle error in an estimated position of a rotor over various loads on an electric motor or type of electric motor. Electrical parameters of an electric motor are measured, a true rotor position is found, and sensorless gains based on the measured parameters are generated, including determining a sensorless angle. Data is gathered at multiple torque levels for at least one speed of the motor, including for each torque level, trying different inductance values, and determining an inductance value that results in an angle error of zero. The angle error is the difference between the true rotor position and the sensorless angle. The inductance value that results in an angle error of zero for each speed may be saved in an electronic memory and used to better control the motor or other motors of the same type.

A method for controlling a variable speed drive arranged for powering an electric motor, the variable speed drive comprising a power part and a control part. The method comprises a preliminary phase of storing a set of predetermined levels of flux of the electric motor. Then, during a current phase, the method comprises selecting a level of flux from among the set of predetermined levels of flux and controlling the power part of the variable speed drive based on the selected level of flux as reference value.

An electric motor control device such that a rotation angle correction value used in a phase correction of an angle sensor rotation angle signal can be calculated with high accuracy is obtained. The electric motor control device includes a rotation angle correction amount calculation unit (30) that, based on a rotation angle signal for an alternating current electric motor (15) output from an angle sensor (16) and a current detection signal for the alternating current electric motor (15) output from a current detection unit (21), calculates a rotation angle correction amount to correct a rotation angle error between the rotation angle signal and a magnetic pole position of the alternating current electric motor (15), wherein the rotation angle correction amount calculation unit (30), based on a current detection signal when a short circuit is caused between winding terminals of the alternating current electric motor (15), calculates at least either one rotation angle correction amount of a direct current component rotation angle correction amount and an alternating current component rotation angle correction amount.

A motor control system has a computing device and a motor controller. The computing device receives user demands through a GUI, and provides a preset speed table based on the user demands. The preset speed table has a plurality of fixed values of a duty cycle of a pulse width modulation signal and a plurality of preset values of a preset motor speed corresponding to the plurality of fixed values of the duty cycle of the pulse width modulation signal. The motor controller provides the pulse width modulation signal to drive a motor based on the preset speed table.

A shift range control device switches a shift range by controlling driving of a motor in a shift range switching system, in which a play exists between a motor shaft which is a rotation shaft of a motor and an output shaft to which the rotation of the motor is transmitted. A parameter calculation unit calculates a motor angle, a motor speed and a motor acceleration based on a motor rotation angle signal acquired from a motor rotation angle sensor which detects a rotation position of the motor. An idling check unit checks an end of idle rotation, in which the motor rotates within a range of the play, based on the motor speed and the motor acceleration. A target setting unit sets a motor angle target value related to drive control on the motor, by using an angle correction value which is a value corresponding to the motor angle at the end of the idle rotation. A drive control unit controls the driving of the motor such that the motor angle becomes the motor angle target value.

A system for reducing at least one of motor loss or motor drive loss in a vehicle. The system includes a motor designed to convert electrical energy into torque. The system also includes a sensor designed to detect motor data corresponding to at least one of a motor torque or a motor speed of the motor. The system also includes a memory designed to store testing data including optimized current commands for multiple combinations of motor torques that were determined during testing of the motor or a similar motor. The system also includes a speed or torque controller coupled to the motor, the sensor, and the memory and designed to receive a speed or torque command and to determine a current command signal usable to control the motor based on the speed or torque command, the testing data, the detected motor data, and an artificial intelligence algorithm.

A duty ratio under different working conditions is determined according to an analysis of a characteristic parameter x of a motor of a power tool and then a drive circuit is controlled with the duty ratio to drive the motor to operate. It is only needed to calculate the duty ratio without needing to make any variable to the circuit hardware or the mechanical structure of the power tool. That is, the duty ratio can be adjusted to achieve optimized control of the motor, thereby optimizing the working performance such as an output torque of the power tool.