Lucent Technologies Inc.

Tyco Electronics Logistics Ag

Marco A Davila

Edward Clark Fontana

Daniel M Kolides

Joyce E Lingousky

Rui Liu

Vincent M Byrne

Steven C Stein

Yimin Jiang

Subhas Chandra Chalasani

Yehoshua Mandelcorn

Xina Shu-Wen Quan

Pradhuman S Zaveri

For use with an asymmetrical half-bridge power converter having a primary switching circuit coupled to a primary winding of a transformer and a rectifier coupled to a secondary winding of the transformer, a reverse recovery circuit a method of operation thereof. In one embodiment, the reverse recovery circuit includes an inductor that reduces current spikes in the primary switching circuit caused by a reverse recovery phenomenon associated with the rectifier. The reverse recovery circuit also includes a diode, coupled to the inductor, that clamps a voltage across the rectifier.

Reverse recovery circuit, method of operation thereof and asymmetrical half-bridge power converter

The present invention provides, in one embodiment, a system for providing fuel to a backup electrical fuel cell. In this particular embodiment, the system includes a sealed fuel container having a pierceable membrane with a container seal associated therewith, an acerate tube proximate the pierceable membrane, and an actuator. The actuator is coupled to the acerate tube and automatically drives the acerate tube through the pierceable membrane to provide fluid communication from the fuel container to the fuel cell in response to a failure of a primary electrical power system. The container seal is configured to form a seal about the acerate tube when the acerate tube pierces the pierceable membrane to prevent unnecessary loss of fuel, such as methanol, from the container. In alternative embodiments, the system may also include the primary power system and a backup electrical fuel cell that is electrically coupled to the primary power system.

System and method for automatically providing fuel to a fuel cell in response to a power failure in a primary power system

A circuit for, and method of, reducing a preload current required to maintain a duty cycle of an asymmetrical DC/DC converter and a DC/DC converter incorporating the circuit or the method. In one embodiment, the circuit includes an auxiliary inductor, coupled in series with an output capacitor of the converter in an output current doubler thereof, that reduces ripple current in the output current doubler and thereby maintains the duty cycle.

Asymmetrical DC/DC converter having output current doubler

There is provided an integrated exclusion filter and pressurizing device which prevents leakage of unfiltered fluid across the interface area between a rotating filtering apparatus and non-rotating bulkhead. The exclusion filter utilized is of the type which utilizes Boundary Layer Momentum Transfer methodology to achieve filtration, and which includes a cylindrical stack of substantially flat annular plates. A pressurizing device is utilized downstream from the exclusion filter to repressurize filtered fluid and direct the filtered fluid toward the interface area. Either all the filtered fluid or only a portion may be repressurized, and some of the filtered fluid may be directed toward the bulkhead itself to aid pressurization by creating a local stagnation region. The pressurizing device may utilize flow diverting vanes in a housing, including blowers, pumps, compressors, and fans. The housing design may be modified to improve fluid flow and multistage pressurizing means designs may be used to enhance repressurization. External vanes may also be added to the filtering apparatus to disperse particles ejected by the exclusion filter, reduce the particle density of the unfiltered fluid surrounding the exclusion filter, cool the system served by the filtering apparatus, or dilute the exhaust of the system served by the filtering apparatus.

Integrated exclusion filter and pressurizing means

The present invention relates to an enhanced exclusion filter having a cylindrical stack of substantially identical annular disks and a central rotating element. Each annular disk engages the rotating element by at least one strut which extends inward from the inner perimeter of the annular disk toward the central axis of the cylindrical stack. Protuberances extend from the annular disks and engage depressions in adjacent annular disks to maintain the spacing between adjacent annular disks. Dimples extending through the annular disks may be utilized to form a depression on one surface of an annular disk and a protuberance on the opposite surface of the annular disk. The annular disks are angularly offset by a fixed amount from the adjacent annular disks so that rough vane surfaces are formed by the struts of the annular disks. Preferably a pattern of substantially identical angular offsets is used. In the alternative, a pattern of angular offsets may be used in which series of small angular offsets are separated by large angular offsets in a direction opposite from the small angular offsets. Preferably, the design of the struts is modified so that the trailing and leading edges of the struts extend toward adjacent struts, forming more continuous vane surfaces. The present invention also relates to the use of exclusion filters as a means of providing a flow of fluid through electronics enclosures. The present invention also relates to the use of redundant pressurized enclosures comprising an enclosure casing, two exclusion filters, and two pressurizing means. The enclosure casing has a major orifice through which fluid enters the enclosure casing and a minor orifice through which fluid exits the enclosure casing. The pressurizing means discharge filtered and pressurized fluid in two discharge areas within the enclosure casings which are substantially opposite from one another.

Enhanced exclusion filter

There is provided an integrated exclusion filter and pressurizing device which prevents leakage of unfiltered fluid across the interface area between a rotating filtering apparatus and non-rotating bulkhead. The exclusion filter utilized is of the type which utilizes Boundary Layer Momentum Transfer methodology to achieve filtration, and which includes a cylindrical stack of substantially flat annular plates. A pressurizing device is utilized downstream from the exclusion filter to repressurize filtered fluid and direct the filtered fluid toward the interface area. Either all the filtered fluid or only a portion may be repressurized, and some of the filtered fluid may be directed toward the bulkhead itself to aid pressurization by creating a local stagnation region. The pressurizing device may utilize flow diverting blades in a housing, including blowers, pumps, compressors, and fans. The housing design may be modified to improve fluid flow and multistage pressurizing means designs may be used to enhance repressurization. External vanes may also be added to the filtering apparatus to disperse particles ejected by the exclusion filter, reduce the particle density of the unfiltered fluid surrounding the exclusion filter, cool the system served by the filtering apparatus, or dilute the exhaust of the system served by the filtering apparatus.

A hybrid standby power system for producing regulated DC electrical power, a method of producing such power and a telecommunications installation that employs either the system or the method. In one embodiment, the system includes: (1) a primary power input, couplable to a primary power source, that accepts primary electrical power subject to interruption, (2) a standby power input, couplable to a standby power source, that accepts unregulated standby electrical power and (3) a power converter, couplable to at least one of the primary and standby power inputs, including a rectifier that rectifies at least one of the primary and standby electrical power to provide unregulated DC electrical power and a DC--DC converter that converts the unregulated DC electrical power into the regulated DC electrical power.

Hybrid standby power system, method of operation thereof and

For use with a reserve battery couplable to a source of electrical power, a battery connect/disconnect circuit, including: (1) a switching subcircuit comprising a series-coupled controllable switch and diode and connected in electrical series with the reserve battery, the diode reverse-biased with respect the source of electrical power, (2) a contactor coupled in electrical parallel with the switching subcircuit and (3) a control circuit, coupled to the switching subcircuit and the contactor, that selectively closes the contactor to couple the reserve battery to the source of electrical power to charge the reserve battery.

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Mesquite, TX, United States of America

Marco A Davila