R&d Dynamics Corporation

Charles William Buckley

Giridhari L Agrawal

Alexander R Nelson

Ali Shakil

Muthusamy Rajendran

Jared Knechel

Andrew Hamilton Coward

Aren Andreas Johansen

A cryogenic oil-free direct drive turbogenerator for gas liquefaction plant applications is described. The pressure energy from cryogenic gas is expanded through a turbine and the power generated is converted into electricity through a directly driven generator and a power electronics arrangement. The machinery can withstand very cold temperature operation (e.g., &#x3c;&#x2212;425&#xb0; F.) by isolating the cold turbine side from the warmer side of the machine turbine end and has a hermetically sealed design wherein the process gas is fully contained from leaking at operating pressures. A unique gas injection scheme uses seal gas segregation, thrust bearing cooling and pressure balance for thrust control which is accomplished through a pressure regulator arrangement. Also described is an algorithm for speed control and overspeed protection through the power electronics system. The rotating components of the turbogenerator are supported on foil gas bearings for oil-free operation eliminating extraneous lubrication.

Cryogenic oil-free direct drive turbogenerator

An electric motor includes a stator; an annular end cap, fastened at a first end of the stator; a threaded seat that is mounted at an outward end face of the annular end cap for receiving a first gas foil thrust bearing; a shaft, inserted through the stator, through the annular end cap, and through the threaded seat; a thrust runner mounted at an end of said shaft adjacent the threaded seat; a first gas foil thrust bearing that is mounted into the threaded seat, adjacent a face of the thrust runner facing the stator; a bearing cap that has a threaded fitting by which it is attached onto the threaded seat; and a second gas foil thrust bearing that is mounted into the bearing cap adjacent to a face of the thrust runner opposite the first gas foil thrust bearing.

Foil bearing supported motor with adjustable thrust bearing cap

An electric motor stator includes an armature surrounding a longitudinal opening for receiving a shaft, with longitudinal fins protruding from an outer surface of said armature; windings are wound within the armature and protruding beyond ends of the armature; and encapsulant seals the windings to the armature, such that the encapsulant serves as an outer housing for the windings.

Foil bearing supported motor with housingless stator

A high-speed, single-stage, motor-driven blower designed to move water vapor includes an axial flow compressor and a rotating assembly supported by gas foil bearings and driven by a brushless permanent magnet synchronous motor utilizing a remotely mounted variable frequency drive. The blower is immersed in a water vapor flow for operation. Accordingly, the blower comprises an outer blower housing and an inner blower housing defining an annular cavity therebetween, wherein the inner blower housing is held within the outer blower housing by seals, and contains and protects the motor components and the bearings against water damage and contamination. A cooling flow may be leaked through the inner blower housing to cool the internal operational components of the blower and to capture heat therefrom, which can be added to the water vapor flow moving through the blower.

Oil-free water vapor blower

A hermetically-sealed turbomachine, such as a motor-driven blower and a turbine driven generator, capable of reliable high-temperature operation, especially for large sized turbomachine includes a hot blower, compressor or turbine end of the turbomachine that is separated from the cooler electric motor, generator or alternator end of the turbomachine by a compliant mechanical coupling and a thermal choke assembly. The turbomachine housing is also hermetically sealed, providing control over the process gas within the machine housing, and permitting an internal cooling method within the turbomachine, whereby a small amount of process gas itself is used within the turbomachine for providing cooling of the rotating shafts, the axial fan, radial fan, or turbine impeller, the bearings and the electric motor, generator or alternator disposed within the turbomachine housing. The cooling method can be aided by a heat exchanger operatively communicating with the turbomachine.

Mechanically-coupled turbomachinery configurations and cooling methods for hermetically-sealed high-temperature operation

A turbine-driven alternator (i.e., a turbomachine) suitable for generating electrical power from process gas waste energy. In particular suitable for very high density process gases such as super critical CO2, R134a, R245fa, etc. The turboalternator comprises two separate machines, specifically, a turbine device and an alternator device operatively connected together by a coupling shaft. The rotating shaft assemblies for each machines on the turbine side and the alternator side are supported by hydrodynamic foil gas bearings. The foil gas bearings use process gas at the turbine side, enabling high-pressure operation (&#x2dc;3000 psia) and thrust load balancing. At the alternator side, cooling fluid is used in the foil gas bearings, enabling high-speed (&#x2dc;40,000 rpm), low-windage, oil-free operation with closed-loop shaft cooling.

Ultra high pressure turbomachine for waste heat recovery

This invention provides a blower design capable of high temperature operation due to use of a self-sustaining cooling scheme through a sealed motor housing in which a cooling circuit can be created, and the use of a thermal barrier across which a temperature gradient may be formed. The thermal barrier may be formed by a thermal choke plate assembly positioned between a hot side and a cold side of the blower to dissipate heat conducted from the hot side. Alternatively, the thermal barrier may be formed by an internal fan ring provided with the blower's rotating assembly to dissipate heat conducted from the blower's impeller. The thermal choke plate assembly and the fan ring may further be used in combination to block heat transfer by all modes between a hot side and a cold side of the blower.

Foil gas bearing supported high temperature centrifugal blower and method for cooling thereof

This invention provides a small, high efficiency, oil-free turbine-driven alternator (i.e. turboalternator) suitable for conversion of stored energy in a process gas to electrical power, facilitating recapture of energy during operation that would otherwise be wasted. The turboalternator includes a turbine and a generating device operatively connected together by a rotating shaft capable of rotating at high speeds. The rotating shaft is supported by foil gas bearings.

Turboalternator with hydrodynamic bearings

This invention provides a small, high efficiency, oil free motor driven compressor/blower suitable for providing pressurized, contamination-free gas and or air to transportation, industrial and aerospace fuel cell systems or other contaminant-intolerant applications. The motor driven compressor/blower rotor assembly is supported by foil air bearings and rotates at high speed by using a high frequency drive. The impeller is a centrifugal type design. The MDC can be easily integrated into the air management system of a fuel cell.

Growing community of inventors

West Hartford, CT, United States of America

Charles William Buckley