Methods and systems are provided for a winch including a motor and a contactor assembly positioned within a same housing. In one example, the contactor assembly is coupled to the motor and includes two or more coils spaced apart from one another within a contactor housing of the contactor assembly and a brush assembly including a plurality of brushes surrounding a rotational axis of the motor and arranged axially to the motor armature.

Methods and systems are provided for a winch including a motor and a contactor assembly positioned within a same housing. In one example, the contactor assembly is coupled to the motor and includes two or more coils spaced apart from one another within a contactor housing of the contactor assembly and a brush assembly including a plurality of brushes surrounding a rotational axis of the motor and arranged axially to the motor armature.

A safety system for a power tool having a motor and a cutting tool driven by the motor includes a control device configured to detect a direct contact of a conductive material with the cutting tool, the direct contact of the conductive material with the cutting tool defining a contact event, and a braking device movable between a retracted position and an engaged position. The control device is configured to interrupt electrical power to the motor and control the braking device to the engaged position when the contact event is detected.

A safety system for a power tool having a motor and a cutting tool driven by the motor includes a control device configured to detect a direct contact of a conductive material with the cutting tool, the direct contact of the conductive material with the cutting tool defining a contact event, and a braking device movable between a retracted position and an engaged position. The control device is configured to interrupt electrical power to the motor and control the braking device to the engaged position when the contact event is detected.

Non-invasive rubbing detection for motors is disclosed. In an embodiment, a method of detecting rubbing on a stator of a motor includes providing an electrical conductor on the stator, (the electrical conductor has a first end and a second end). The method further includes determining that there is rubbing on a surface of the stator, including by probing the first end and the second end to determine whether there is an electrical connection across the electrical conductor, and determining that there is rubbing on the stator if there is no electrical connection. In an embodiment, the electrical conductor is disposed on the surface of the stator by etching away conductive foil to form the electrical conductor, and providing the electrical conductor.

Non-invasive rubbing detection for motors is disclosed. In an embodiment, a method of detecting rubbing on a stator of a motor includes providing an electrical conductor on the stator, (the electrical conductor has a first end and a second end). The method further includes determining that there is rubbing on a surface of the stator, including by probing the first end and the second end to determine whether there is an electrical connection across the electrical conductor, and determining that there is rubbing on the stator if there is no electrical connection. In an embodiment, the electrical conductor is disposed on the surface of the stator by etching away conductive foil to form the electrical conductor, and providing the electrical conductor.

According to one embodiment, a power generation system includes a power generator, a displacement measuring part, and a converter. The power generator includes a movable part and converts mechanical energy of the movable part into electric power. The displacement measuring part measures a displacement of the movable part. The converter includes a switching circuit whose duty ratio is controlled based on the measured displacement, and converts a voltage level of the electric power.

According to one embodiment, a power generation system includes a power generator, a displacement measuring part, and a converter. The power generator includes a movable part and converts mechanical energy of the movable part into electric power. The displacement measuring part measures a displacement of the movable part. The converter includes a switching circuit whose duty ratio is controlled based on the measured displacement, and converts a voltage level of the electric power.

A method and system for detecting a fault in a permanent magnet synchronous motor (PMSM), operably connected to a controller. The method includes receiving at a controller a stator voltages and currents for the PMSM, computing a negative sequence current and a negative sequence voltage for the PMSM; and determining if conditions are satisfied for monitoring for a fault of the PMSM. The method also includes ascertaining a change in the negative sequence current and a change in the negative sequence voltage for a selected time duration, calculating a ratio of the change in the negative sequence current and the negative sequence voltage corresponding to a negative sequence admittance for the PMSM, determining if the negative sequence admittance differs from a nominal value in excess of a threshold; and identifying the stator winding as faulted if the ratio exceeds the threshold.

A method and system for detecting a fault in a permanent magnet synchronous motor (PMSM), operably connected to a controller. The method includes receiving at a controller a stator voltages and currents for the PMSM, computing a negative sequence current and a negative sequence voltage for the PMSM; and determining if conditions are satisfied for monitoring for a fault of the PMSM. The method also includes ascertaining a change in the negative sequence current and a change in the negative sequence voltage for a selected time duration, calculating a ratio of the change in the negative sequence current and the negative sequence voltage corresponding to a negative sequence admittance for the PMSM, determining if the negative sequence admittance differs from a nominal value in excess of a threshold; and identifying the stator winding as faulted if the ratio exceeds the threshold.