Abstract: A method of controlling a generator system connected to an electric power system in which the output frequency characteristic of the generator system is measured, a first phase angle and frequency of the measured frequency characteristic is estimated using a first phase locked loop having a first bandwidth, and a second phase angle and frequency of the measured frequency characteristic is estimated using a second phase locked loop having a second bandwidth greater than the first bandwidth. Further, the method calculates a frequency difference between the first and second estimated frequencies, and an angle variation that is proportional to the calculated frequency difference. The estimated second phase angle is then added to the calculated angle variation so as to form an output current phase angle reference, and an output current phase angle of the generator system is controlled to be aligned with the output current phase angle reference.

Abstract: A continuous power supply may include a turbogenerator to provide power to supply the load and or an energy storage element and possibly also to the primary energy source. Utilizing an isolated DC bus architecture permits bi-directional power flow among interconnected elements.

Abstract: A power generation system is disclosed. In one embodiment, the power generation system includes a fuel source, a turbogenerator coupled to the fuel source, and a power controller coupled to the turbogenerator. The power controller includes an AC/DC power converter that converts AC power generated by the turbogenerator to DC power on output lines for supplying a DC load. The power controller regulates the fuel to the turbogenerator, independent of a DC voltage on the output lines. A capacitor such as an electrochemical capacitor or a hybrid capacitor, coupled across the output lines, sources power to and/or sinks power from the output lines due to load changes by the DC load. In a further embodiment, the power controller includes an additional DC/DC power converter. In yet a further embodiment, the power controller includes a second additional DC/DC power converter to controllably couple the capacitor to a DC bus.

Abstract: Upon shutdown of a liquid fuel turbine engine, the liquid fuel supply is turned off and compressed air is passed through the fuel lines and fuel injectors to purge all remaining liquid fuel into the combustion chamber to be combusted therein.

Abstract: A method of controlling a generator system connected to an electric power system in which the output frequency characteristic of the generator system is measured, a first phase angle and frequency of the measured frequency characteristic is estimated using a first phase locked loop having a first bandwidth, and a second phase angle and frequency of the measured frequency characteristic is estimated using a second phase locked loop having a second bandwidth greater than the first bandwidth. Further, the method calculates a frequency difference between the first and second estimated frequencies, and an angle variation that is proportional to the calculated frequency difference. The estimated second phase angle is then added to the calculated angle variation so as to form an output current phase angle reference, and an output current phase angle of the generator system is controlled to be aligned with the output current phase angle reference.

Abstract: A power generation system includes a turbogenerator having a motor/generator and a turbine coupled to a common shaft, and generates AC power. A first power converter is coupled to the turbogenerator and a DC bus and converts the AC power to DC power on the DC bus. A second power converter is coupled to the DC bus and is couple-able to a load. The second power converter converts the DC power on the DC bus to an output power for coupling to the load. Also coupled to the DC bus are a battery and a capacitor to stabilize a DC voltage on the DC bus during load changes. The power generation system further includes a power controller coupled to the turbogenerator and the first and second power converters. The power controller regulates a speed of the turbine, independent of the DC voltage on the DC bus.

Abstract: In an integrated turbogenerator system having an air intake for a compressor to supply combustion air to a combustor, an electric brake device such as a resistor is connected to the electrical power output of the turbogenerator and is situated in the air intake to be cooled by the stream of combustion air flowing into the intake. When load transients require unloading excess electrical power produced by the turbogenerator, the brake resistor is supplied with at least part of the excess electrical power to create heat energy and thereby heat the in-flowing combustion air to lower the combustor efficiency, turbogenerator power produced, and excess electric power to be unloaded. An algorithm may be provided for controlling the turbogenerator speed deceleration rate to maintain the brake resistor at or near a physical temperature limit.

Abstract: The present invention provides a gas-turbine engine and a combustion system that include a catalytic reactor and a turbine. The catalytic reactor oxidizes low BTU fuel to generate thermal energy. The turbine converts the thermal energy produced by the catalytic reactor into mechanical energy. This mechanical energy can be used, for example, to produce electricity. The gas-turbine engine and the catalytic combustion system are capable of oxidizing fuels having a higher heating value in a range of between 1000 and 5 BTU/scf.

Abstract: The present invention provides a method for sustained catalytic combustion of low BTU fuels in a gas-turbine engine, and applications thereof. The method comprises ingesting fuel and combustion air into a catalytic reactor to produce thermal energy and converting the thermal energy to mechanical energy with a turbine. The fuel and the combustion air are mixed to form a fuel-air mixture. The ingested combustion air is used to oxidize the ingested fuel. Fuels having a higher heating value in a range of between 1000 and 5 BTU/scf are mixed with the combustion air and oxidized using the catalytic reactor.

Abstract: A turbogenerator system including a recuperator and a catalytic combustor employs a preheater located between the turbine outlet and the recuperator low-pressure inlet to heat the low-pressure turbine exhaust. Heat from the turbine exhaust is transferred to a cool high-pressure flow in the recuperator. A recirculation loop employs valves downstream of the recuperator low-pressure outlet to divert the recuperator low-pressure exhaust into the compressor to be recirculated through the recuperator high-pressure side and the catalytic combustor. Reduced start-up times and emissions are achieved by raising the combustor catalyst to its light-off temperature in a shorter period of time.

Abstract: A fuel delivery system supplies fuel to a turbogenerator or to another heat engine. A fuel delivery system according to the present disclosure may include a fuel compressor, a fuel control valve, and a fuel flow controller. A fuel delivery system may have multiple modes of control permitting independent and simultaneous control by the compressor and the fuel valve. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: According to the present disclosure, a turbogenerator system may be combined with other heat/energy sources. A simple cycle or recuperated cycle turbogenerator have a variety of fuel options and grid connect or stand alone capability that can be combined with one or more external heat sources such as a Solar Collector/Receiver Heat Energy System, a Bio-mass Gasifier/Combustor Heat Energy System, a Fuel Cell Heat/Energy System, a Nuclear Heat/Energy System, a Waste Heat/Energy System, or some other suitable Heat/Energy System. The above external heat systems can be used to provide all of part of the heat/energy input to operate the turbogenerator and achieve electrical output, as well as a turbogenerator hot exhaust flow that has potential for other uses. Using an integral turbogenerator low emission combustor and fuel control as part of these combined systems has additional advantages.

Abstract: The invention provides integrated turbogenerators having a turbine wheel, a compressor impeller, and a motor generator mounted to or mechanically constrained to a common shaft, and improved components and configurations thereof.

Abstract: The invention provides integrated turbogenerators having a turbine wheel, a compressor impeller, and a motor generator mounted to or mechanically constrained to a common shaft, and improved components and configurations thereof.

Abstract: The present disclosure provides a turbogenerator system having a turbine mounted for rotation on a shaft, a motor/generator coupled with the shaft for rotation therewith. A combustor for combusting fuel and compressed air to generate combustion gases for rotating the turbine is provided as well as a compressor providing compressed air, and an injector having at least one opening to admit the compressed air from the compressor. The injector may be connected to the combustor to inject fuel and compressed air into the combustor. A piston slidably covering the at least one opening in the injector provides a variable entry to the compressed air, and a pressure actuator associated with the piston and responsive to pressure in the combustor is used for determining the size of the variable entry. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.

Abstract: A turbogenerator/motor controller with a microprocessor based inverter having multiple modes of operation with an energy storage and discharge system including an ancillary electric storage device, such as a battery, connected to the generator controller through control electronics. Electrical energy can flow from the ancillary electric storage device to the turbogenerator controller during start up and increasing load and vice versa during self-sustained operation of the turbogenerator. When utility power is unavailable, the ancillary electric storage device can provide the power required to start the turbogenerator. When a load transient occurs, the gas turbine engine and the ancillary electric storage device provide the power required to successfully meet the transient.

Abstract: Upon shutdown of a liquid fuel turbine engine, the liquid fuel supply is turned off and compressed air is passed through the fuel lines and fuel injectors to purge all remaining liquid fuel into the combustion chamber to be combusted therein.

Abstract: A turbogenerator cooling system is disclosed that has a cylindrical heat sink with generally axially extending fins on both the outside and inside of a hoop section. The hoop section is solid except for holes adjacent to the rear end thereof. The generator stator is press-fitted into the heat sink in contact with the internal fins. The generator rotor is fitted with a small fan for directing heated air away from the inlet of the engine. Cooling air passes along the external fins to the rear of the generator, flows through the holes in the hoop section passes forward between the inside of the hoop section and the external surface of the stator to cool the stator and along an alternate path to cool the rotor hollow sleeve and permanent magnetic shafts as well as the stator.

Abstract: A method and system to automatically restart a permanent magnet turbogenerator/motor when a fatal fault is detected. The automatic restart logic includes time constraints and limitations on the number of iterations, and is useful regardless of whether the permanent magnet turbogenerator/motor is in a grid connect mode or a standalone mode, and regardless of how the fatal fault originates or is detected. Additional control logic is utilized to handle grid transients and over load conditions to prevent a fatal fault from occurring by using time constraints and an iterative process, together with a brake resistor to control DC bus voltage.

Abstract: A rotary machine includes a helical flow compressor/turbine and a permanent magnet motor/generator including a housing with a stator positioned therein. A shaft is rotatably supported within the housing. A permanent magnet rotor is mounted on a shaft and operatively associated with the stator. An impeller is mounted on the shaft and includes an impeller disk with a plurality of impeller blades extending therefrom. The housing includes a generally horseshoe-shaped fluid flow stator channel with an inlet at a first end and an outlet at a second end. The fluid in the generally horseshoe-shaped fluid flow stator channel proceeds from the inlet to the outlet while following a generally helical flow path with multiple passes through the impeller blades. The impeller disk has a plurality of axially-oriented vent holes formed therethrough to minimize a pressure differential across the impeller, thereby minimizing thrust loads applied to the impeller.