Abstract: Permanent magnets are mounted on a rotor of an electrical motor by an apparatus that keeps an adhesive bonding layer between the magnet and rotor in compression over wide variations in temperature and speed of rotation. The mechanical stresses on the magnets are controlled using compliant layers and spacers. The apparatus allows the removal and replacement of individual magnets.

Abstract: A method and control system for directional drilling are described. A drill string motor is commanded to rotate at a constant speed in a forward direction and the constant speed in a reverse direction for a first duration and a second duration, respectively, for at least one oscillation cycle. The difference between an averaged absolute angle of the drill string and a target rotation angle for the drill string is maintained near zero by adjusting the length of the durations as necessary. The target rotation angle can be changed based on measurement while drilling data obtained during drilling operations. Advantageously, friction between the drill string and bore hole is reduced, leading to an increase in the drilling penetration rate.

Abstract: Permanent magnets are mounted on a rotor of an electrical motor by an apparatus that keeps an adhesive bonding layer between the magnet and rotor in compression over wide variations in temperature and speed of rotation. The mechanical stresses on the magnets are controlled using compliant layers and spacers. The apparatus allows the removal and replacement of individual magnets.

Abstract: A method and control system for directional drilling are described. A drill string motor is commanded to rotate at a constant speed in a forward direction and the constant speed in a reverse direction for a first duration and a second duration, respectively, for at least one oscillation cycle. The difference between an averaged absolute angle of the drill string and a target rotation angle for the drill string is maintained near zero by adjusting the length of the durations as necessary. The target rotation angle can be changed based on measurement while drilling data obtained during drilling operations. Advantageously, friction between the drill string and bore hole is reduced, leading to an increase in the drilling penetration rate.

Abstract: An apparatus and method for controlling an actuator system having an electrical actuator in hydraulic communication with a hydraulic actuator are described. The apparatus includes a controller module in communication with a source of electrical power and a transceiver. The transceiver is adapted for bi-directional wireless communication with a remote transceiver for the transfer of control data and feedback data. The controller module sends a control signal to the electrical actuator in response to control data received from the remote transceiver. The source of electrical power includes a hydraulic motor and an electrical generator to provide local electrical power from a hydraulic flow. Because the electrical power is generated locally and the control and feedback data are carried over the wireless link, no wires to remote locations are required.

Abstract: An arrangement of coils of different configurations for use in the stator of a slotless radial gap electromotive machine is described. The coils include coils of a first configuration and a second configuration. Each coil includes longitudinal sections and circumferential sections that form a substantially rectangular opening in the coil. The coils are nested together along the inside of a stator core so that the longitudinal sections of each coil of the first configuration are disposed in the rectangular openings of neighboring coils of the second configuration, and the longitudinal sections of the coils of the second configuration are disposed in the rectangular openings of neighboring coils of the first configuration. Other configurations of coils can be nested together inside the stator core to provide one or more additional layers of stator coils.

Abstract: An apparatus for determining the angular position of a rotating component having a plurality of angularly spaced magnetic elements is described. The apparatus includes a sensor board and a processor circuit. The sensor board is disposed adjacent to the rotating component and includes a plurality of sensor groups. Each sensor group includes a plurality of magnetic sensors positioned to sense a magnetic field of one of the angularly spaced magnetic elements. Each sensor group generates a multi-state group signal in response to the passage of one of the angularly spaced magnetic elements. The processor circuit communicates with each of the sensor groups and generates position signals in response to the multi-state group signals.