A brushless DC motor configured with an external rotor includes an analysis and control unit, a stator, a rotor, a co-rotating bell, and a sensor that detects an angular position of the rotor. A target with at least one electrically conductive track is attached to the co-rotating bell, and the sensor is configured as an eddy current sensor with at least one coil. The sensor is arranged at a radial distance from the target such that the at least one electrically conductive track at least partly covers the at least one coil. The sensor provides an angle signal as a function of the at least one coil being covered by the at least one electrically conductive track. The angle signal uniquely represents the absolute angular position of the rotor up to 360. A method includes providing an angle signal for the brushless DC motor.

A brushless DC motor configured with an external rotor includes an analysis and control unit, a stator, a rotor, a co-rotating bell, and a sensor that detects an angular position of the rotor. A target with at least one electrically conductive track is attached to the co-rotating bell, and the sensor is configured as an eddy current sensor with at least one coil. The sensor is arranged at a radial distance from the target such that the at least one electrically conductive track at least partly covers the at least one coil. The sensor provides an angle signal as a function of the at least one coil being covered by the at least one electrically conductive track. The angle signal uniquely represents the absolute angular position of the rotor up to 360. A method includes providing an angle signal for the brushless DC motor.

An Integrated Starter Generator system (100) comprising a battery (110) and a three-phase brushless DC electric machine (130). The electric machine (130) has a stator (132) with 3n stator teeth (132), n being a natural number, and each stator tooth (132) has a coil corresponding to one of the three phases. The electric machine (130) further has a rotor (134) with 4n rotor poles (134) facing the stator (132), and magnets on the rotor poles (134) are disposed with an alternating sequence of magnet polarity facing the stator (132). Herein, back-emf constant of the electric machine (130) is substantially between 25% of a nominal battery voltage and 75% of the nominal battery voltage.

A method of changing a magnetic flux density in an air gap between a stator and a rotor in a real-time flux-mnemonic permanent magnet synchronous machine comprising permanent magnets, the method comprising applying at least one current pulse to adjust a magnetic operating point of the magnets, wherein the at least one current pulse has a duration of less than 3 ms. For applying the at least one current pulses, the method comprises consecutively applying a plurality of primitive pulses.

A method of changing a magnetic flux density in an air gap between a stator and a rotor in a real-time flux-mnemonic permanent magnet synchronous machine comprising permanent magnets, the method comprising applying at least one current pulse to adjust a magnetic operating point of the magnets, wherein the at least one current pulse has a duration of less than 3 ms. For applying the at least one current pulses, the method comprises consecutively applying a plurality of primitive pulses.

A hand-guided gardening, forestry and/or construction processing device includes a processing tool, an electric motor drive system, wherein the electric motor drive system is designed to drive the processing tool, a user-adjustable operating element, and a control device. The control device is designed to control a target slope rate of a rotational speed of the electric motor drive system in dependence on a position of the operating element according to at least one allocation in such a way that maximum target slope rates of the rotational speed differ for different positions.

A motor control device is provided that enables smooth rotation control from a low-speed region to a high-speed region. A microcomputer of the motor control device calculates the rotation speed of a rotor from the time between edges that appear per 60 electrical angle at the time of starting the motor, from a signal that is output when a the hall sensor detects the magnetic field of a rotating rotor and, in conjunction with an increase in the rotation speed of the rotor, calculates the rotation speed of a rotor from the time between edges that appear at electrical angles that are larger than the electrical angle 60 in the signal, per 180 electrical angle, per 360 electrical angle, per 900 electrical angle, and per 1800 electrical angle.

Provided is a remote controller for controlling an object placed in a remote location. The remote controller may include: a communication interface configured to form a communication channel with the object; an operator including an input interface configured to receive a user input, and at least one first magnet; a movement sensor configured to detect a movement of the operator generated by the user input, and measure characteristics of the movement of the operator; at least one second magnet disposed around the first magnet; a controller configured to, in response to the detection of the movement, apply a current to at least one of the first magnet and the second magnet to generate a magnetic force applied to the operator, wherein the controller is further configured to adjust the current to change the magnetic force according to the measured characteristics of the movement of the operator.

A system for providing closed-loop control of a linear resonant actuator using Back Electromotive Force (EMF) and inertial compensation is disclosed. In an embodiment, one or more inertial sensors are used to estimate low frequency motion of a haptic engine moving mass and compensate for the motion using a feedforward model, thus providing a more robust closed-loop control system for controlling the moving mass when subjected to low frequency disturbances by a user, for example, shaking or swinging the device.

A system for providing closed-loop control of a linear resonant actuator using Back Electromotive Force (EMF) and inertial compensation is disclosed. In an embodiment, one or more inertial sensors are used to estimate low frequency motion of a haptic engine moving mass and compensate for the motion using a feedforward model, thus providing a more robust closed-loop control system for controlling the moving mass when subjected to low frequency disturbances by a user, for example, shaking or swinging the device.