Abstract: A line-start synchronous motor has a housing, a rotor shaft, and an output shaft. A soft-start coupling portion is operatively coupled to the output shaft and the rotor shaft. The soft-start coupling portion is configurable to enable the synchronous motor to obtain synchronous operation and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling. The synchronous motor is sufficiently rated to obtain synchronous operation and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling.

Abstract: A rotor comprises laminations with a plurality of rotor bar slots with an asymmetric arrangement about the rotor. The laminations also have magnet slots equiangularly spaced about the rotor. The magnet slots extend near to the rotor outer diameter and have permanent magnets disposed therein creating magnetic poles. The magnet slots may be formed longer than the permanent magnets disposed therein and define one or more magnet slot apertures. The permanent magnets define a number of poles and a pole pitch. The rotor bar slots are spaced from adjacent magnet slots by a distance that is at least 4% of the pole pitch. Conductive material is disposed in the rotor bar slots, and in some embodiments, may be disposed in the magnet slot apertures.

Abstract: A method includes forming a lamination that may be used in a rotor of an interior permanent magnet motor or further processed for use in a line-start interior permanent magnet motor. The lamination has been optimized for low cogging, minimal usage of magnet material, and maximum torque per ampere and may be further processed to include rotor bars slots to allow the lamination's use in connection with an LSIPM. In accordance with the method, the lamination is formed with magnet slots that are radially inward of the outer diameter. The magnet slots are formed in a plurality of V-shaped arrangements. Each V-shaped arrangement has a leading edge and a trailing edge. The leading edge and trailing edge are arranged such that when the leading edge aligns with a stator tooth, the respective trailing edge is generally not aligned with a stator tooth.

Abstract: A superconducting coil system includes a superconducting coil and a protective link of superconducting material coupled to the superconducting coil. A rotating machine includes first and second coils and a protective link of superconducting material. The second coil is operable to rotate with respect to the first coil. One of the first and second coils is a superconducting coil. The protective link is coupled to the superconducting coil.

Abstract: Apparatus and methods are provided for a system for measurement of a current in a conductor such that the conductor current may be momentarily directed to a current measurement element in order to maintain proper current without significantly increasing an amount of power dissipation attributable to the current measurement element or adding resistance to assist in current measurement. The apparatus and methods described herein are useful in superconducting circuits where it is necessary to monitor current carried by the superconducting elements while minimizing the effects of power dissipation attributable to the current measurement element.

Abstract: Apparatus and methods are provided for a system for measurement of a current in a conductor such that the conductor current may be momentarily directed to a current measurement element in order to maintain proper current without significantly increasing an amount of power dissipation attributable to the current measurement element or adding resistance to assist in current measurement. The apparatus and methods described herein are useful in superconducting circuits where it is necessary to monitor current carried by the superconducting elements while minimizing the effects of power dissipation attributable to the current measurement element.

Abstract: A method is provided for testing an electrical characteristic of a rotor. In one embodiment, the method may include applying current to the rotor, measuring voltage drop between first and second positions on the rotor, and evaluating the electrical characteristic of the rotor based at least on the voltage drop and the current. In another embodiment, the method may include coupling a first set of leads to a first end portion of the rotor at a first set of angular positions about an axis of the rotor. The method also may include coupling a second set of leads to a second end portion of the rotor at a second set of angular positions about the axis of the rotor. In addition, the method may include coupling the first and second sets of leads to a current source to provide a current flow through the rotor from the first end portion to the second end portion. Furthermore, the method may include engaging a first probe to the first end portion and a second probe to the second end portion to measure voltage drop.

Abstract: A method is provided for testing an electrical characteristic of a rotor. In one embodiment, the method may include applying current to the rotor, measuring voltage drop between first and second positions on the rotor, and evaluating the electrical characteristic of the rotor based at least on the voltage drop and the current. In another embodiment, the method may include coupling a first set of leads to a first end portion of the rotor at a first set of angular positions about an axis of the rotor. The method also may include coupling a second set of leads to a second end portion of the rotor at a second set of angular positions about the axis of the rotor. In addition, the method may include coupling the first and second sets of leads to a current source to provide a current flow through the rotor from the first end portion to the second end portion. Furthermore, the method may include engaging a first probe to the first end portion and a second probe to the second end portion to measure voltage drop.

Abstract: A system for providing DC current to a rotating superconducting winding is provided. The system receives current feedback from the superconducting winding and determines an error signal based on the current feedback and a reference signal. The system determines a control signal corresponding to the error signal and provides a positive and negative superconducting winding excitation voltage based on the control signal.

Abstract: An apparatus compares the torque from an MOV motor with the valve displacement, and from the comparison assesses MOV operating condition. A transducer measures the vibration of the housing of an MOV. The vibrations are due to the motions of the rotating elements within the housing, which motions are directly related to the motion of the valve relative to its seat. Signal processing apparatus analyzes the vibrations to recover the rotations of the rotating elements and thus the motion of the valve plug. Lost motion can also be determined (if a lost motion connection exists) by demodulating the vibration signal and thus taking into account also the lost motion. Simultaneously, the forces applied to the valve are estimated by estimating the torque between the stator and the rotor of the motor. Such torque can be estimated from measuring the input current and voltage alone, using a forgetting factor and a correction for the forgetting factor.