Sundstrand Corporation

Other

David W Lefavour

Thomas Albert Sutrina

Roy S Baker

A variable reluctance generator for producing alternating current at a fundamental frequency independent of a rotational speed at which the generator is driven in accordance with the invention includes a rotor having a plurality of salient poles disposed around a circumference and projecting radially outward from an axis of rotation; a stator having a plurality of salient poles disposed about an inner circumference and projecting radially inward toward the rotor; at least one stator phase winding wound on the stator for outputting the electrical power of the fundamental frequency; an exciter winding wound on the stator; an electrical load coupled to the at least one stator phase winding; a position detector for providing a rotor position signal representing a rotary position of the rotor; a first switching circuit, responsive to the rotor position signal, for applying time varying excitation current at the fundamental frequency or a multiple thereof to the exciter winding in a series of pulses of varying magnitude which define the fundamental frequency and are produced by current flow through the exciter winding by switching of the first switching circuit to cause the current flow in each current pulse and each pulse being timed in relation to an occurrence of a lowest reluctance rotary position of the salient poles of the rotor and stator during rotation of the salient poles of the rotor between adjacent salient poles of the stator so as to generate a pulse on the at least one stator phase winding in response to a pulse on the exciter winding and rotation of the rotor away from the low reluctance rotary position; a current sensor for detecting a direction of current flow in the electrical load; and a second switching circuit, coupled to the at least one stator phase winding and to the electrical load and responsive to the current sensor, for controlling a direction of current flow through the electrical load so that each pulse applied to the exciter winding produces a corresponding pulse in the electrical load without backflow of current.

Variable reluctance alternating current generator

A poly-phase no-break power transfer phase balance synchronization sense circuit for an electric power generation and distribution system having a present source of electric power supplying poly-phase AC electric power through a first contactor to utilization equipment and a target source of electric power connectable to supply poly-phase AC electric power to the utilization equipment through a second contactor, a transfer of the source of AC electric power from the present source to the target source being accomplished by closing the second contactor prior to opening the first contactor upon synchronization of the two sources, comprises a circuit for rectifying the poly-phase AC electric power generated by the present source, the circuit generating a first rectified output signal, a circuit for rectifying the poly-phase AC electric power generated by the target source, the circuit generating a second rectified output signal, and a circuit for differentially summing the first rectified output signal and the second rectified output signal. This summing circuit generates a synchronization error signal in response to any phase of the poly-phase AC electric power generated by the present source differing in magnitude, phase relationship, or frequency from an associated phase of the poly-phase AC electric power generated by the target source. This synchronization error signal varies in magnitude in response to the magnitude of the difference. The circuit further comprises a circuit for generating a power transfer inhibit signal when the variable magnitude of the synchronization error signal exceeds a predetermined threshold.

No-brake power transfer phase balance sychronization sense circuit and

A flash tube is provided for producing successive high intensity bursts of light, and a pulse producing device is provided for supplying a train of high voltage pulses for energizing repeatedly the flash tube. An impedance matching arrangement is provided and includes a first unidirectional device which couples the output of the alternator to the pulse producing device for energizing it periodically during half cycles of the alternating current output of the alternator. The arrangement also includes a second unidirectional device which the output of the alternator to an auxiliary lighting device to energize it during alternate half cycles of the alternator. As a result, the alternator supplies lower instantaneous current to both loads at a favorable operating characteristic of the source.

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Rockford, IL, United States of America

David W Lefavour