Disclosed herein are various embodiments of devices and related methods for detecting an electrical arc event using a motor management relay and for suppressing the electrical arc event. The motor management relay may incorporate an optical arc-flash sensor configured to detect an optical event. Control logic may analyze the optical event and determine whether the optical event corresponds to an electrical arc event. When an electrical arc event is detected an instruction may be issued via a control port in communication with the control logic to implement a protective action. According to various embodiments, a plurality of sensors for monitoring electrical characteristics of a motor may also be in communication with the control logic. Input from the sensors may be analyzed in order to determine whether the optical event corresponds to an electrical arc event.

The invention results in improved switching from the idling mode to an active short circuit mode of an electric machine. According to the invention, the switch from the idling mode to the active electric short circuit mode is delayed until predefined voltage conditions have been reached on the external terminals of an electric machine or until the rotor of the electric machine is in a predetermined position corresponding to the required voltage conditions.

An electric motor with a motor shaft, a motor pinion and a sensor element for an optical rotary encoder which has at least one recess for the transmission of a light beam from the optical rotary encoder. The motor shaft, the motor pinion and the sensing element being integrally formed with one another and being coupled with the motor shaft in a rotationally fixed manner. Further, the sensor element has a drum-shaped design and is aligned coaxially with the motor pinion. The recess is formed in the sensor element in such a way that the light beam of the rotary encoder can pass radially relative to a rotational axis of the sensor element. The invention also relates to a medical device with such an electric motor.

An estimate of the initial position of a rotor is made by monitoring sensed motor current signals which are amplitude and phase modulated with the rotor flux position in response to a high frequency voltage signal injection. The motor current signals are envelope detected to determine zero crossing points. Samples are taken of the motor current signals at positive and negative offsets from the zero crossing point, with the samples processed to identify a direction of the rotor flux axis. Further samples of at least one motor current signal are taken with respect to a certain phase reference, and the samples compared to resolve a polarity of the rotor flux axis which is indicative of the angular position of the rotor.

An assembly of stator modules for a planar drive system comprises a first stator module and a second stator module, The first stator module and/or the second stator module each comprise stator segments with a segment width, the stator segments being energizable, where the stator segments can provide a magnetic field in order to interact with the magnet arrangements of a rotor for driving and/or holding the rotor of the planar drive system. The first stator module and the second stator module are arranged spaced apart from each other and thereby form a gap, where the gap has a gap width, and where the gap width is smaller than or equal to the segment width.

An assembly of stator modules for a planar drive system comprises a first stator module and a second stator module, The first stator module and/or the second stator module each comprise stator segments with a segment width, the stator segments being energizable, where the stator segments can provide a magnetic field in order to interact with the magnet arrangements of a rotor for driving and/or holding the rotor of the planar drive system. The first stator module and the second stator module are arranged spaced apart from each other and thereby form a gap, where the gap has a gap width, and where the gap width is smaller than or equal to the segment width.

A mounting structure of a rotating member of an encoder for detecting a phase angle of a magnet provided on a rotor of a motor includes: a rotating shaft configured to be rotated by driving of the motor; the rotating member on which a phase angle detection pattern configured to detect the phase angle is formed; and a boss attached to the rotating member and configured to mount the rotating member to an end of the rotating shaft. In this configuration, the end of the rotating shaft and the boss are provided with a first positioning structure configured to position a mounting position of the boss relative to the rotating shaft about the axis of the rotating shaft.

A motor drive control device driving a motor having a first system coil and a second system coil, the motor drive control device comprising: a first drive circuit controlling energization of the first system coil; a second drive circuit controlling energization of the second system coil; and a signal output circuit detecting a first voltage that is a voltage at a middle point of the first system coil and a second voltage that is a voltage at a middle point of the second system coil, and outputting an output signal concerning whether or not any one of the first system coil and the second system coil is in an open state, based on a detection result of the first voltage and a detection result of the second voltage.

A direct current (DC) motor for operation in an external magnetic field may include a rotor which is rotatable about a rotation axis and has at least two windings, at least four continuous rotary transmitters, wherein two rotary transmitters are associated with each of the windings and are configured to supply the associated winding with direct current, an angle sensor which is configured to determine the angular position of the rotor, and a controller configured to control the current feed to at least one of the windings dependent upon the angular position of the rotor. The motor is oriented relative to an external magnetic field during operation so that the rotation axis extends transversely to the external magnetic field.

A method for obtaining an initial mechanical angle of an electric motor includes determining a mechanical state of the electric motor, determining an initial electrical angle of the electric motor according to the mechanical state, and determining the initial mechanical angle of the electric motor according to the initial electrical angle.