Electricity: power supply or regulation systems – Including an impedance
Reexamination Certificate
2008-07-22
2008-07-22
Nguyen, Matthew V (Department: 2838)
Electricity: power supply or regulation systems
Including an impedance
C323S205000, C323S208000
Reexamination Certificate
active
07402990
ABSTRACT:
A method and an apparatus for reducing energization transients in a three phase AC power system which includes an electrical device having legs A, B and C associated with corresponding phases of the power system. The method includes the steps of connecting the legs of the device with the power system in an order determined by an energization sequence, wherein the energization sequence is either ABC or ACB. The apparatus includes a three phase electrical device having legs A, B, and C associated with corresponding phases of a three phase AC power system and switches operable to connect the legs of the device with the power system, wherein the switches are configured to be actuated in an order determined by an energization sequence, and wherein the energization sequence is either ABC or ACB. The switches may be controlled by a switch controller. A transient-limiting impedance may be connected in series with leg A of the device, in which case the method of the invention includes the further step of bypassing the transient-limiting impedance and the energization sequence is either ABCI, ABIC, ACBI or ACIB, wherein I is the step of bypassing the transient-limiting impedance. In the apparatus of the invention, a bypass switch may be provided for bypassing the transient-limiting impedance, which bypass switch may be controlled by the switch controller.
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Nguyen Matthew V
Wong Cabello Lutsch Rutherford & Brucculeri LLP
Xu Wilsun
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