A motor driver circuit includes: a current detection circuit configured to generate a current detection signal according to a drive current of a motor as an object to be driven; a first amplifier configured to amplify the current detection signal; a second amplifier configured to multiply a voltage across the motor by a gain smaller than 1 and output the multiplied voltage; and a third amplifier configured to generate a back electromotive force detection signal according to a difference between an output of the first amplifier and an output of the second amplifier.

The present invention provides a linear motor driving voltage generation method and related devices. It is designed to use the driving voltage generated by the driving voltage generation method to effectively control the linear motor to express the vibration effect in a specific direction. The method of the present invention includes: Define the displacement waveform of the linear motor’s vibrator within a preset period. The displacement waveform is an asymmetrical waveform. Calculate the voltage waveform corresponding to the linear motor in the preset period according to the displacement waveform.

The present invention enables the user to perceive the vibration of the linear motor in a specific direction.

The present invention provides a linear motor driving voltage generation method and related devices. It is designed to use the driving voltage generated by the driving voltage generation method to effectively control the linear motor to express the vibration effect in a specific direction. The method of the present invention includes: Define the displacement waveform of the linear motor’s vibrator within a preset period. The displacement waveform is an asymmetrical waveform. Calculate the voltage waveform corresponding to the linear motor in the preset period according to the displacement waveform.

The present invention enables the user to perceive the vibration of the linear motor in a specific direction.

A linear motor is disclosed, the linear motor comprising a longitudinal coil assembly comprising coil units arranged in a cascading manner and a magnet track spaced from the coil assembly, and adapted to move along a path which traces a periphery of the coil assembly. The linear motor further comprises sensors, each sensor being associated with a subset of the coil units, and adapted to send a first sensor signal in response to detecting the magnet track. The linear motor further comprises a control unit, wherein the control unit is configured to receive the first sensor signal, identify the sensor which sent the first sensor signal, and power up the subset of the coil units associated with the sensor.

A planar drive system comprises a stator and a rotor. The stator comprises a plurality of energizable stator conductors. The rotor comprises a magnet device having at least one rotor magnet. A magnetic interaction can be produced between energized stator conductors of the stator and the magnet device in order to drive the rotor. The stator is configured to carry out energization of the stator conductors so that an alternating magnetic field can be generated via the energized stator conductors. The rotor comprises at least one rotor coil in which an alternating voltage can be induced due to the alternating magnetic field. The planar drive system is configured to transmit data from the rotor to the stator, and the rotor is configured to temporarily load the at least one rotor coil to temporarily cause increased current consumption of the energized stator conductors of the stator.

A planar drive system comprises a stator and a rotor. The stator comprises a plurality of energizable stator conductors. The rotor comprises a magnet device having at least one rotor magnet. A magnetic interaction can be produced between energized stator conductors of the stator and the magnet device to drive the rotor. The stator is configured to carry out energization of the stator conductors so that an alternating magnetic field can be generated via the energized stator conductors. The rotor comprises at least one rotor coil in which an alternating voltage can be induced due to the alternating magnetic field. The planar drive system is configured to transmit data from the stator to the rotor, and the stator is configured to temporarily influence the energization of the stator conductors in order to temporarily cause a change with respect to the alternating voltage induced in the at least one rotor coil.

A method for controlling a planar drive system includes controlling a rotor along a control path starting from a first position on a stator module, and determining a sensor pattern for magnetic field sensors of a sensor module. The sensor pattern includes a subset of the magnetic field sensors with at least one of the magnetic field sensors not comprised by the sensor pattern, and an area of the sensor pattern is at least partially covered by the rotor in a position along the control path. The method includes measuring values of the rotor magnetic field with the aid of the magnetic field sensors of the sensor pattern, detecting the rotor, and determining a second position of the rotor based on the measured values. The invention further relates to a planar drive system.

Systems and methods are provided for braking a translator of a linear multiphase electromagnetic machine. The system detects a fault event, and in response to detecting the fault event, causes the translator to brake using an electromagnetic technique. Braking includes causing the translator to stop reciprocating, by applying a force opposing an axial motion, which may occur within one cycle, or over many cycles. The fault event may include, for example, a fault associated with an encoder, a controller, an electrical component, a communications link, a phase, or a subsystem. The system includes a power electronics system configured to apply current to the phases. The system may use position information, current information, operating parameters, or a combination thereof to brake. Alternatively, the system need not use position information, current information, and operating parameters, and may brake the translator independent of such information.

Systems and methods are provided for braking a translator of a linear multiphase electromagnetic machine. The system detects a fault event, and in response to detecting the fault event, causes the translator to brake using an electromagnetic technique. Braking includes causing the translator to stop reciprocating, by applying a force opposing an axial motion, which may occur within one cycle, or over many cycles. The fault event may include, for example, a fault associated with an encoder, a controller, an electrical component, a communications link, a phase, or a subsystem. The system includes a power electronics system configured to apply current to the phases. The system may use position information, current information, operating parameters, or a combination thereof to brake. Alternatively, the system need not use position information, current information, and operating parameters, and may brake the translator independent of such information.

A motor controller is provided that executes a commutation routine in one of a plurality of operating modes to regulate current provided to drive coils in a linear motion system. The motor controller generated currents for each of the drive coils in a first operating mode to minimize the copper losses in the drive coils, in a second operating mode to maximize the force applied to the mover, in a third operating mode to provide balanced currents between the drive coils, and in a fourth operating mode to provide currents according to a selected operating point that combines characteristics of the first three operating points. The motor controller may also monitor each of the drive coils for saturation and redistribute at least a portion of the current required to control operation of the mover to the other drive coils when one of the drive coils is saturated.