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Premerlani, William James

Publications and source records attributed to Premerlani, William James.

Transformer system

A flexible transformer system includes conductive windings extending around a magnetic core of a transformer phase and impedance-varying windings extending around the magnetic core of the transformer phase. The conductive windings and the impedance-varying windings are configured to conduct electric current around the magnetic core of the transformer phase. The system includes an impedance switch coupled with the impedance-varying windings and with the conductive windings. The impedance switch is configured to change an impedance of the system by changing which impedance-varying winding of the impedance-varying windings is conductively coupled with the conductive windings and which impedance-varying winding of the impedance-varying windings is disconnected from the conductive windings.

Premerlani, William James↗

Hybrid Direct-Current Circuit Breaker

A circuit breaking system includes a first branch including at least one solid-state snubber; a second branch coupled in parallel to the first branch and including a superconductor and a cryogenic contactor coupled in series; and a controller operatively coupled to the at least one solid-state snubber and the cryogenic contactor and programmed to, when a fault occurs in the load circuit, activate the at least one solid-state snubber for migrating flow of the electrical current from the second branch to the first branch, and, when the fault is cleared in the load circuit, activate the cryogenic contactor for migrating the flow of the electrical current from the first branch to the second branch.

Wang, Ruxi↗