A motor starter and a method for starting an electric motor are disclosed. In an embodiment, the motor starter includes a phase gating unit and a control unit. The phase gating unit is configured to be deactivated via the control unit after an activity period of the phase gating unit has elapsed and is configured to be deactivated during operation after the activity period has elapsed.

The present invention relates to a motor driving device which can reduce a load burden on a rotating shaft when a magnetic bearing is initially operated. When a rotor and a stator are initially aligned, the motor driving device can apply a greater current to a coil positioned farthest away from the ground among a plurality of coils than to the other coils, so as to reduce a levitation force necessary for initial alignment of the rotor and the stator.

The present invention relates to a motor driving device which can reduce a load burden on a rotating shaft when a magnetic bearing is initially operated. When a rotor and a stator are initially aligned, the motor driving device can apply a greater current to a coil positioned farthest away from the ground among a plurality of coils than to the other coils, so as to reduce a levitation force necessary for initial alignment of the rotor and the stator.

The invention relates to a motor starter (10) for an electric motor (20), wherein the motor starter (10) comprises a first and a second phase (12, 14). Said motor starter and electric motor each have an associated switching apparatus (29, 31) which each have an electromechanical switch (22, 24) and a semiconductor switch (23, 25) connected to form a bypass circuit. The electromechanical switches (22, 24) and the semiconductor switches (23, 25) are designed to be separately operable by a control unit (40), and the first and the second phase (12, 14) are connected to a passive overcurrent protection means (30). The passive overcurrent protection means (30) has a fuse (32, 34, 36) for each phase. According to the invention, a measuring apparatus (42, 44) is arranged in at least one of the phases (12, 14) along the phase direction directly between the passive overcurrent protection means (30) and at least one of the switching apparatuses (29, 31). The invention further relates to diagnosis methods (100, 200, 300) with which defects in the motor starter (10) can be diagnosed during an activation sequence.

The invention relates to a motor starter (10) for an electric motor (20), wherein the motor starter (10) comprises a first and a second phase (12, 14). Said motor starter and electric motor each have an associated switching apparatus (29, 31) which each have an electromechanical switch (22, 24) and a semiconductor switch (23, 25) connected to form a bypass circuit. The electromechanical switches (22, 24) and the semiconductor switches (23, 25) are designed to be separately operable by a control unit (40), and the first and the second phase (12, 14) are connected to a passive overcurrent protection means (30). The passive overcurrent protection means (30) has a fuse (32, 34, 36) for each phase. According to the invention, a measuring apparatus (42, 44) is arranged in at least one of the phases (12, 14) along the phase direction directly between the passive overcurrent protection means (30) and at least one of the switching apparatuses (29, 31). The invention further relates to diagnosis methods (100, 200, 300) with which defects in the motor starter (10) can be diagnosed during an activation sequence.

A motor driving system is configured for driving a motor, which is under an inertial rotation status without being driven, to stably rotate from an original speed to a target speed. The motor driving system includes a sensing unit, a control unit and a driving unit. The sensing unit detects a real rotating status of the motor. The control unit is electrically connected with the sensing unit and provides a gradual acceleration command based on the real rotating status. The driving unit is electrically connected with the control unit and drives the motor to accelerate stably to the target speed according to the gradual acceleration command. In addition, a motor operation recovering method cooperated with the motor driving system is also disclosed.

A motor driving system is configured for driving a motor, which is under an inertial rotation status without being driven, to stably rotate from an original speed to a target speed. The motor driving system includes a sensing unit, a control unit and a driving unit. The sensing unit detects a real rotating status of the motor. The control unit is electrically connected with the sensing unit and provides a gradual acceleration command based on the real rotating status. The driving unit is electrically connected with the control unit and drives the motor to accelerate stably to the target speed according to the gradual acceleration command. In addition, a motor operation recovering method cooperated with the motor driving system is also disclosed.

A BLDC motor and a method for starting and operating the motor. The motor has a rotor with exciter magnets, a stator with at least three stator coils, and a control and evaluation unit. The method carries out an initialization phase with a defined start time, initial starting field angle of the stator magnetic field and angle rising rate. A partial cycle is carried out with a rising phase that increases a current field angle with a change in voltage application to the stator coils. An analysis phase keeps the current field angle constant. The method continuously records a difference in current between two phase currents of a same direction of flow, the evaluation unit analyzes the recorded difference for the presence of a current eye. Immediate commutation takes place when a current eye is detected or where without detection after a pre-definable time interval has elapsed. The analysis phase is terminated after commutation is carried out. The partial cycle is repeatedly carried out until the final field angle has increased to a value of 360 to define a total cycle.

A power tool includes a motor and a power supply for supplying power to the motor. A driving circuit is connected to the motor. A voltage detection unit is used for detecting the voltage of the motor. A controller is configured to perform the following operations: if the motor voltage is greater than or equal to a preset voltage, the driving circuit will apply a voltage to the motor with a second slope, wherein the value range of the second slope is from 0 to 0.3. The disclosure also discloses a control method for starting under load of a power tool.

A controller for a drive motor (60) of a product conveyor belt at a checkout has a phase-start cutting and/or phase-end cutting controller (50) that controls the drive motor (60) in such a manner that the product conveyor belt is accelerated with reduced torque from a non-driven state. A start controller controls the drive motor (60) in such a manner that the drive motor (60) initially drives with a non-reduced torque when accelerating the product conveyor belt from the non-driven state before the phase-start cutting and/or phase-end cutting controller (50) further accelerates the product conveyor belt with reduced torque.