General Electric Company

Lockheed Martin Corporation

William George Earls

Michael Joseph Schutten

Robert Louis Steigerwald

Ravisekhar Nadimpalli Raju

Ljubisa Dragoljub Stevanovic

Ramanujam Ramabhadran

Systems and methods for providing automatic short circuit protection in an electrical system via a switching device. In some embodiments, the switching device includes a switching transistor that selectively switches between an open position and a closed position based at least in part on a switching control signal, for example, to facilitate converting electrical power with first electrical characteristics output into electrical power with the second electrical characteristics. Additionally, the switching device includes a protection transistor electrically coupled in series with the switching transistor, in which a constant gate voltage is supplied to the protection transistor to maintain the first protection transistor in the closed position during operation of the power converter; and the protection transistor automatically limits current flow through the first switching device by reducing a gate voltage applied to the switching transistor when a short circuit is expected to be present in the electrical system.

Automatic short circuit protection switching device systems and methods

A high current inductor is constructed using two single-sided or double-sided printed circuit boards having patterned copper traces thereon, a magnetic toroidal core, and multiple interconnecting wires extending between the boards. Multiple turns for the inductor are created by suitably configuring the copper traces on the printed circuit boards. Vias are employed on each circuit board for electrically interconnecting the boards to each other. Multiple thick, solid-gauge wires are situated in the vias in order to provide a very large copper area, thus providing high current carrying capability.

High current inductor and method for making same

Non-destructive EMI susceptibility testing involves near-field injection of very high levels of instantaneous energy and low average power through localized injection of signals of very high field strength and low duty cycle. An electric field injector and a magnetic field injector are scanned, each in turn, over the equipment under test. For each injector, the amplitude and frequency of the induced localized electric or magnetic field, respectively, is varied such that the susceptibility locations, magnitudes, and frequencies can be identified and mapped. This approach localizes which section or subcircuit of the equipment under test is susceptible, the frequencies and field strengths of susceptibility, and whether susceptibility problems are created by magnetic fields, electric fields, or both.

EMI susceptibility testing apparatus and method

A bulk current injection (BCI) system and method for testing electromagnetic susceptibility of electrical apparatus includes an RF modulator in a BCI setup. The BCI setup with RF modulator injects high instantaneous currents with a very low, controllable duty cycle into a wire under test, thereby simulating an electromagnetic environment to which electrical equipment is exposed during an electrical transient event. The RF modulator provides an amplitude modulated envelope for removing undesirable transients. Injecting currents at selectable frequency, one frequency at a time, allows for frequency-amplitude electromagnetic susceptibility mapping for each major wire within an electrical apparatus.

Bulk current injection system

A switching converter achieves improved regulation range by the use of a saturable reactor in series with a transformer primary. The saturable reactor uses a conventional magnetic pot core including a magnetic shell and center post. The location at which the post joins the shell is perforated to reduce the cross-section of magnetic material, so that, at low reactor currents, incremental inductance is established by the gap between post and lid, and at high reactor currents, the incremented inductance is established by saturation at the base of the post. Perforation at the base of the post also results in generation of heat at a location immediately adjacent the flat bottom of the pot core.

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Schenectady, NY, United States of America

William George Earls