A motor-driving control system includes an actuator configured to generate rotational force by driving received current, a current provider configured to provide current to the actuator while repeatedly turning on and off the current at a preset period and duty, and a controller configured to estimate a rotation position or a rotation speed of the actuator in a section in which the current of the current provider is turned on or off and to control the current provider to follow a speed command based on the estimated rotation position or rotation speed.

A determination method and apparatus for a brushless direct current counter-electromotive force zero crossing point threshold and a storage medium, the method includes detecting counter-electromotive force zero crossing point time intervals of two adjacent sectors of a brushless direct current electric motor to obtain at least two first time intervals; utilizing the obtained at least two first time intervals to determine errors of a counter-electromotive force zero crossing point; converging the determined errors of the counter-electromotive force zero crossing point to obtain a counter-electromotive force zero crossing point threshold correction increment; and utilizing the obtained counter-electromotive force zero crossing point threshold correction increment to determine a counter-electromotive force zero crossing point threshold.

A cart may include: a carriage; a wheel supported by the carriage and touching ground; a holding member rotatably supported by the carriage about a steering axis and rotatably supporting the wheel about a rotation axis; a steering handle to be gripped by a user; an input sensor configured to detect an operation on the steering handle by the user; a steering motor configured to be actuated in response to the operation by the user detected by the input sensor; and a transmission mechanism connecting the steering motor and the holding member and configured to rotate the holding member about the steering axis in response to actuation of the steering motor. The steering handle and the transmission mechanism may be mechanically separated, and the transmission mechanism may include a torque limiter interposed between the steering motor and the holding member.

A method for moving a rotor in a planar drive system having a first and second stator modules and a rotor. The stator modules are arranged at a distance, forming a gap. First and second magnetic fields are generated by the first and stator modules. The first and second magnetic fields hold the rotor in a vertical position, at a distance from a surface of the first and/or second stator module. The first and/or second magnetic fields have a first magnetic field strength to maintain the rotor in the vertical position, and may be used to change a horizontal position of the rotor. The first stator module has a first close range adjacent the gap, where the first magnetic field has a second field strength when the rotor is moved across the gap, greater than the first magnetic field strength.

The disclosure describes techniques to filter unwanted noise from feedback signals of an electrical machine. An electrical machine may receive AC power from an inverter and circuitry in the inverter may cause noise on the AC power signals to the electrical machine. The noise may couple to sensors for the electrical machine and cause noise in the sensor output signals. The sensor output signals may provide feedback for a closed loop control system for the electrical machine and noise may impact the closed loop operation. Also, the noise in the feedback signals may cause electromagnetic compatibility (EMC) issues, either by direct radiated emissions or by coupling to other circuits in the vehicle wiring harness as the feedback signals travel from the electrical machine. The techniques of this disclosure may include filter circuitry located near or inside the electrical machine that filters out the unwanted noise in the feedback signals.

Systems and methods for determining proper phase rotation in a linear motor that may be used in an ESP system, where the phase rotations associated with power and return strokes are initially unknown. The method includes providing power to the motor for multiple cycles and monitoring the load (e.g., by monitoring current drawn by the motor) on the motor to determine in which direction (phase rotation) the load on the motor increases. This direction corresponds to the power stroke of the motor. The direction of increasing load is then associated with the power stroke and the motor is operated normally.

The present disclosure relates to a motor driving method, which includes the following steps: detecting a detected voltage value between a first switch and a second switch in a driving circuit, wherein the driving circuit is configured to control the first switch and the second switch according to a switching frequency to provide a driving current to a motor device; determining a driving current according to the detected voltage value; when the driving current is less than a predetermined value, the first switch and the second switch are turned off for a detection period, wherein the length of the detection period is a fixed value; during the detection period, detecting a back electromotive force to calculate a zero crossing time of the back electromotive force; and adjusting the switching frequency according to the zero crossing time.

A method of adaptively controlling a brushless DC motor includes steps of: controlling the brushless DC motor rotating at a first speed according to an operation curve, accumulating a running time of the brushless DC motor, estimating a remaining used time of a bearing of the brushless DC motor according to the accumulated running time, executing an alarm operation when the remaining used time is less than a predetermined time, and decreasing the speed of the brushless DC motor to run at a second speed to prolong the used time of the bearing.

AC motor rotates independent from power frequency gives advantages in size and controllability. Oscillating and rotating magnetic field is created across airgap by using Amplitude Modulated input. Higher frequency (Carrier) is the power input and the lower frequency (Signal) determines speed of the motor. Stator and Rotor work as primary and secondary of transformer, rotor windings are arranged to keep resultant EMF generated within the winding as zero when rotor aligned with stator magnetic field and increase when deviates. The current generated on deviated rotor winding creates a push back torque keeping the rotor aligned with magnetic field. This interlocks magnetic field and the rotor. Two different frequencies are applied at either end of the stator windings so that the current flow through each winding become amplitude modulated, average of the two frequencies become carrier frequency and control frequency is half of the difference between two frequencies.

A haptic engine includes a haptic actuator having a double-wound driving coil in which the two windings are connected with each other either in series or in parallel. By using the double-wound driving coil in which the two windings are connected with each other in series, an instant back EMF voltage induced in either of the two windings can be determined without having to measure in real time a resistance of the corresponding winding, and without having to sense a driving current through the double-wound driving coil. By using the double-wound driving coil in which the two windings are connected with each other in parallel, an instant back EMF voltage induced in either of the two windings can be determined without having to measure in real time a resistance of the corresponding winding.