Abstract: An aspect of the invention is directed to a variable sensor head for use in multiple electric machines with varying slot openings comprising a ferromagnetic core; a first adjustable portion and a second adjustable portion positioned in communication with the ferromagnetic core wherein the first adjustable portion and the second adjustable portion are adjusted to fit between a plurality of slot openings of varying widths between a pair of lamination teeth of an electric machine. According to another embodiment, the first and second adjustable portions are sliding portions where the sliding portions may be spring biased to provide a close fit between the pair of lamination teeth. According to another embodiment, the first and second adjustable portions are adjustable screws.

Abstract: An online insulation condition monitoring system for a rotating electric machine, includes a differential current sensor and a voltage sensor coupled to the machine, for measuring values for the instantaneous differential current and the instantaneous phase voltage respectively. A processing module is configured for converting the values for the instantaneous differential current and the instantaneous phase voltage to respective values for phasor current and phasor voltage. The processing module further calculates an angular relationship between phasor current and phasor voltage and generates an output based on the calculated angular relationship, as an indication of insulation condition.

Abstract: A synchronous electric machine having a rotor member and a stator member having a stator core is provided. The electric machine further includes a main machine having a direct current (DC) rotor field winding mounted on the rotor member; and a dual (AC/DC) excitation system. The excitation system includes a rotatable polyphase armature winding in electrical communication with a rectifier assembly for conducting direct current to the rotor field winding of the main machine, and a plurality of DC salient poles and at least one alternating current (AC) salient pole both included in the stator core. A magnetic axis of respective AC field coils is disposed substantially in electromagnetic space-quadrature relation with respect to magnetic axes of adjacent DC field coils, wherein when the respective AC field coils are energized, an alternating current is induced in the polyphase armature winding for providing excitation to the main machine.

Abstract: A winding of an electric machine is provided, where the winding includes at least one series of serially connected AC bars. Each AC bar includes a series of serially connected turns formed by litz wire having a plurality of strands, and at least one cooling tube. Individual strands of the plurality of strands are respectively positioned substantially adjacent to the at least one cooling tube at at least one transfer point for providing heat transfer from the respective individual strands to the at least one cooling tube.

Abstract: A single-stage process for drying, roasting, and grinding of green coffee beans in a single unit operation in a continuous manner. Heat-treated and ground coffee beans having savory flavor and aroma are achieved in a unique process described herein that combines all these different treatments in a single-stage operation.

Abstract: A fault current limiter (FCL) comprises: an air core flat clock spiral inductor comprising wound electrically conductive material and insulated turns; and two terminations configured for attaching the spiral inductor in series with a power carrying conductor.

Abstract: Electric machines can be improved or uprated to reduce core-end losses using lower core loss material such as high grade iron silicon. A machine uprating entails removing at least a last one of the stacked lamination packages at each end of the stator core, and re-stacking the removed lamination packages with the lower core loss material.