A permanent magnet electrical machine has a rotor supporting a circumferential row of permanent magnets and a stator coaxial with the rotor and having a circumferential row of teeth carrying respective coil windings. The teeth provide paths for magnetic flux from the magnets, thereby electromagnetically linking the magnets and coils when the rotor rotates. The teeth have respective core portions on which the coil windings are mounted, and respective tip portions located between the core portions and the rotor. The tip portions are controllably rotatable between a first position where the tip portion and the core portion are angularly aligned to enhance magnetic flux linkage between the magnets and the coils, and a second position in which the tip portion is rotated out of angular alignment with its core portion to reduce magnetic flux linkage between the magnets and the coils. The tip portions are biased to the second position.

A variable frequency starter generator (VFSG) system includes a VFSG having a start mode and a generate mode, a permanent magnet generator (PMG) and a main generator section and an exciter section. The system also includes a controller electrically connected to the VFSG. The controller flow start mode three phase electrical power from aircraft power to the exciter of the VFSG in the start mode and flows single phase electrical power to the exciter of the VFSG in the generate mode. The controller includes: a passive rectifier that receives input AC power and converts it to DC power and provides it to across a positive rail and negative rail; an output inverter coupled to an output of the passive rectifier; and one or more line inductors connected along one or both of the positive rail and negative rail between the passive rectifier and the output inverter.

A power module includes a turbine arranged along a rotation axis, an interconnect shaft fixed in rotation relative to the turbine, and a compressor with a regenerative compressor wheel. The regenerative compressor wheel is fixed in rotation relative to the interconnect shaft supported for rotation with the turbine about the rotation axis. Generator arrangements, unmanned aerial vehicles, and methods of generating electrical power are also described.

An electric generator includes a turbine wheel configured to receive process gas and rotate in response to expansion of the process gas flowing into an inlet of the turbine wheel. A rotor is coupled to the turbine wheel and can rotate with the turbine wheel in a stator. The electric generator generates a current upon rotation of the rotor within the stator. A power electronics system is electrically connected to an electrical output of the electric generator and receives alternating current from the electric generator. A fast stop valve resides proximate and upstream from an inlet conduit of the electric generator. The fast stop valve can quickly shut upon detection of a fault condition at the power electronics or the grid, to prevent an overspeed of the rotor.

An aircraft electrical system including: a first DC power bus and a fuel cell assembly including a first fuel cell group, wherein the first fuel cell group is electrically coupled directly to the first DC power bus without a voltage converter to provide a first power output to the first DC power bus.

An electrical machine has a variable reluctance rotor, and a stator formed as an annular array of stator segments. The reluctance of the rotor-to-stator magnetic flux path varies with rotor position whereby the stator segments are magnetically energizable to rotate the rotor. The stator segments are arranged in the array such that, when energized to rotate the rotor, they produce an unbalanced force on the rotor. The machine further has a compensator including one or more balancing segments which are configured to be magnetically energizable to produce a balancing force on the rotor which balances the unbalanced force. The reluctance of the rotor-to-compensator magnetic flux path is substantially invariant with rotor position.

A turbine pump assembly has a turbine, a centrifugal pump, and a passive electrical speed control system. The turbine has a peak efficiency at a first speed that is lower than a second speed at which the centrifugal pump is operating at a peak power requirement. A rocket thrust vector control system is also disclosed.

The present invention is directed to a direct-drive fan system and a variable process control system for efficiently managing the operation of fans in a cooling system such as a wet-cooling tower or air-cooled heat exchanger (ACHE), HVAC systems, mechanical towers or chiller systems. The present invention is based on the integration of key features and characteristics such as tower thermal performance, fan speed and airflow, motor torque, fan pitch, fan speed, fan aerodynamic properties, and pump flow. The variable process control system processes feedback signals from multiple locations in order control a high torque, variable speed, permanent magnet motor to drive the fan. Such feedback signals represent certain operating conditions including motor temperature, basin temperature, vibrations, and pump flow rates. Other data processed by the variable process control system in order to control the motor include turbine back pressure set-point, condenser temperature set-point and plant part-load setting. The variable process control system processes this data and the aforesaid feedback signals to optimize the operation of the cooling system in order to prevent disruption of the industrial process and prevent equipment (turbine) failure or trip. The variable process control system alerts the operators for the need to conduct maintenance actions to remedy deficient operating conditions such as condenser fouling. The variable process control system increases cooling for cracking crude and also adjusts the motor RPM, and hence the fan RPM, accordingly during plant part-load conditions in order to save energy.

An electrical power generation system including: a micro-turbine alternator, including: a decomposition chamber; a turbine including blades driven by combustion gases from the decomposition chamber; a blower operably connected to the decomposition chamber to provide a blown airflow thereto; one or more shafts connecting the turbine to the blower such that rotation of the turbine drives rotation of the blower; an electric generator disposed along the one or more shafts such that electrical power is generated via rotation of the one or more shafts; and a housing enclosing the electric generator within a generator cavity formed therein. The blower is configured to blow air through the generator cavity through or around the electric generator. The air is configured to exit the generator cavity to enter the turbine.

A low cost, high power density, low emissions general aviation turbine engine (GATE) with improved fuel economy over current engines. Ideally suited for 50 to 500 shaft horsepower (SHP) range aircraft applications such as GA, UAS, UAS, air taxi, helicopters and commercial markets. The engine design features with centrifugal compressor and radial turbine rotors has a high-end practical limit of ?800 (SHP). The new turboprop incorporates 2 non-concentric spools aero-thermal-pressure coupled wherein staged compressor rotors lend to a simple engine design, optimized high overall engine pressure ratio (OPR) and low specific fuel consumption (SFC). An integral startergenerator system further simplifies the engine design and offers high electrical output power capability for auxiliary power requirements. A 2-stage low emissions combustor with fuel-air premix chambers is incorporated lending to stable combustion at any engine spool speed/power requirement, further fuel optimization and use of a low cost simple fixed pitch propeller. Some other highlights include: any fuel or mixture thereof, TBO greater than piston or other turbine engines, less maintenance costs, oil/filter change at ?15000 hrs. and other inherent advantages of a gas turbine engine. Of the two spools that make up this turboprop engine, one is the High Pressure (HP) spool that is part of the gas generator using combustor hot gases to power the integral HP turbine rotor, HP compressor and high-speed alternator startergenerator. The other engine spool is the Low-Pressure (LP) spool that receives the HP turbine exhaust heat energy to power the integral LP compressor rotor, LP turbine rotor, integrated gearbox with resultant output shaft horsepower. This invention represents the most advanced engine for general aviation since Charles Edward Taylor's engine powered the Wright Brothers first aircraft-controlled powered flight Dec. 17, 1903.