A permanent magnet speed governor having a fixed magnetic gap. The permanent magnet speed governor includes an outer magnetic rotor and an inner magnetic rotor, at least two outer permanent magnets being evenly distributed along the circumferential direction of the inner circumferential surface of the outer magnetic rotor, the magnetic poles of the outer permanent magnets being arranged along the radial direction, the magnetisms of exposed magnetic pole surfaces of two adjacent outer permanent magnets being different. At least one rotatable permanent magnet is distributed along the circumferential direction of the outer circumferential surface of the inner magnetic rotor, the rotatable permanent magnet being cylindrical and the N pole and the S pole being along the diametrical direction, one end of the rotatable permanent magnet being provided with a magnetic circuit regulator. It increases the engagement area of the speed governor.

A permanent magnet speed governor having a fixed magnetic gap. The permanent magnet speed governor includes an outer magnetic rotor and an inner magnetic rotor, at least two outer permanent magnets being evenly distributed along the circumferential direction of the inner circumferential surface of the outer magnetic rotor, the magnetic poles of the outer permanent magnets being arranged along the radial direction, the magnetisms of exposed magnetic pole surfaces of two adjacent outer permanent magnets being different. At least one rotatable permanent magnet is distributed along the circumferential direction of the outer circumferential surface of the inner magnetic rotor, the rotatable permanent magnet being cylindrical and the N pole and the S pole being along the diametrical direction, one end of the rotatable permanent magnet being provided with a magnetic circuit regulator. It increases the engagement area of the speed governor.

A controller of the electric brake device includes a reaction force compensator to perform compensation such that a rotational resistance, of an electric motor, generated by a reaction force to a pressing force of a friction member against a brake rotor is cancelled out. The reaction force compensator includes: a direct estimator to directly estimate the reaction force from information including at least either a drive voltage or current of the electric motor and at least either a rotational angle of the electric motor or a value obtained by differentiating the rotational angle one or more times; an indirect estimator to estimate the reaction force from an estimated braking force on the basis of a set correlation; and a compensation reaction force determiner to determine a reaction force, to perform the compensation, by using estimation results of direct estimation and indirect estimation at predetermined proportions.

A controller of the electric brake device includes a reaction force compensator to perform compensation such that a rotational resistance, of an electric motor, generated by a reaction force to a pressing force of a friction member against a brake rotor is cancelled out. The reaction force compensator includes: a direct estimator to directly estimate the reaction force from information including at least either a drive voltage or current of the electric motor and at least either a rotational angle of the electric motor or a value obtained by differentiating the rotational angle one or more times; an indirect estimator to estimate the reaction force from an estimated braking force on the basis of a set correlation; and a compensation reaction force determiner to determine a reaction force, to perform the compensation, by using estimation results of direct estimation and indirect estimation at predetermined proportions.

A method for monitoring the performance of a mechanical brake for a linear electromagnetic motor, the linear motor having a linearly moveable output shaft, comprising monitoring travel of the output shaft over the duration of actuation of the mechanical brake and comparing said travel with a predetermined travel threshold.

A method for controlling a braking system of an electromagnetic motor, the electromagnetic motor having a moveable output shaft, comprising the steps of: receiving a velocity signal and/or an acceleration signal based on movement of the output shaft, said velocity signal and/or acceleration signal having a respective frequency spectrum; identifying an event from the velocity and/or the acceleration signal using the respective frequency spectrum, wherein said event corresponds to an uncontrolled movement of the output shaft and has a characteristic frequency spectrum.

A mechanical brake for arresting movement of the output shaft of a linear electric motor, comprising a pivotally mounted plate having a space for receiving the output shaft of the motor; an electrically operated holding device contacting a free end of the plate and arranged to hold the plate in a condition to permit movement of the output shaft and to permit the plate to pivot to a jamming position; wherein the electrically operated holding device comprises a solenoid to control the movement of the plate.

A method for preventing motion of an output shaft (401), of an electromagnetic motor comprising a coil assembly, when a mechanical brake (400) is released, comprising the steps of: determining the position of the output shaft (401); correlating the position of the output shaft (401) with a current such that when applied in the coil assembly induces a force on the output shaft (401) to prevent motion of the output shaft (401) when the mechanical brake (400) is released.

A magnetic gear embedded rotating electric machine control device, which controls voltage applied to a stator winding of a rotating electric machine having a magnetic gear therein so that an output from the rotating electric machine follows an output command, includes: a damping command generator which generates a damping command using an angle between a stator and a high-speed rotor of the rotating electric machine detected by an angle detector; a first adder which adds the damping command to the output command, to generate a corrected output command; and an output controller which controls an output generated by the rotating electric machine, in accordance with the corrected output command.

A magnetic gear embedded rotating electric machine control device, which controls voltage applied to a stator winding of a rotating electric machine having a magnetic gear therein so that an output from the rotating electric machine follows an output command, includes: a damping command generator which generates a damping command using an angle between a stator and a high-speed rotor of the rotating electric machine detected by an angle detector; a first adder which adds the damping command to the output command, to generate a corrected output command; and an output controller which controls an output generated by the rotating electric machine, in accordance with the corrected output command.