Abb Schweiz Ag

Wen Ouyang

Darren Dale Tremelling

Jun Li

Jiaqi Liang

Zhiguo Pan

Ghanshyam Shrestha

Hongrae Kim

Harish Suryanarayana

Waqas Mahmood Arshad

Jan Mikael Westerlund

Li Qi

Colin Tschida

Varagur Ramanan

Jukka Pekka Kittila

Ora Veli-Matti Leppänen

Darren Tremeling

Unique systems, methods, techniques and apparatuses for a ZVT ZCT resonant converter with a variable resonant tank are disclosed. One exemplary embodiment is a system comprising a bidirectional resonant converter comprising an input/output terminal, a switching device coupled with the input/output terminal, a resonant circuit coupled with the switching device and including a variable inductor, an output/input terminal coupled with the resonant circuit, and a DC biasing circuit operatively coupled with the variable inductor. The variable inductor comprises a toroidal core, a first winding wound around the toroidal core and coupled with the switching device and the output/input terminal, a second core structured to overlap a portion of the toroidal core, and a second winding wound around the second core and coupled with the DC biasing circuit. The DC biasing circuit is controllable to vary the inductance of the variable inductor by saturating a portion of the toroidal core.

Variable inductor apparatuses systems and methods

An electrical machine includes a stator and a rotor in magnetic communication with the stator. The rotor has a cage construction, the rotor having a plurality of passages extending therethrough from a first end of the rotor to a second end of the rotor. A rotor cage has two end rings, one of the end rings disposed at each of the first end and the second end of the rotor, and having a plurality of conductor bars extending through the rotor from the first end to the second end and coupled with the end rings. The conductor bars each include a transition region adjacent to each end ring, and a central region disposed between the two transition regions. Each transition region includes at least one conductor bar dimension that increases proximate the end rings.

Electrical machines and methods for manufacturing electrical machines

A electromagnetic machine system includes a rotor and a stator positioned about the rotor. A current injection mechanism is coupled with windings of the stator and structured to inject electrical currents therein so as to change a flux distribution of a magnetic field produced by the stator. The injected currents may be harmonic currents. The rotor further includes an inductor positioned to interact with the magnetic field when the flux distribution is changed, to produce an electrical excitation current for exciting windings in the rotor. The machine system may be a synchronous motor or generator, and may be brushless. Applications of the current injection strategy to direct torque control and vector control are also disclosed.

Electromagnetic machine system having current injection for inductive excitation of windings

A permanent magnet machine with a hybrid cage and methods for operating same are disclosed. According to one aspect, the subject matter described herein includes a rotor and hybrid cage for an electrical machine, the rotor comprising a rotor body having a central axis and including a plurality of permanent magnets positioned to create a plurality of rotor magnetic poles distributed around a peripheral surface of the rotor. The rotor also includes a hybrid cage that includes conductive loops around each of the rotor magnetic poles, where the conductive loops are controllable to form a closed circuit or an open circuit around each of the rotor magnetic poles. A closed circuit may be created when a magnetic field having a field strength or change of field strength that exceeds a threshold magnitude is present, such as during a fault condition, and an open circuit may be created when a magnetic field having a field strength or change of field strength that exceeds a threshold magnitude is not present, such as during normal operation.

Permanent magnet machine with hybrid cage and methods for operating same

A synchronous machine system comprising a synchronous motor including a stator, stator winding, rotor, and field winding; an AC power supply circuit structured to transmit current to or from the stator winding of the synchronous motor at a controlled frequency and transmit current to or from a power source at a controlled frequency; a DC exciter unit structured to receive power from a power source, convert the received power to DC power at a desired voltage, and supply the converted power across a DC bus to the field winding of the synchronous motor; and an energy storage circuit coupled to the DC bus of the DC exciter unit having at least one ultracapacitor, and structured to receive power from a power source, to charge the ultracapacitor, and to provide power to the field winding of the synchronous motor following a power failure.

Ultracap-based solutions for ride-through of synchronous machine drives

A synchronous machine and related systems include a stator and rotor separated by an air gap. The rotor includes a rotating DC power supply coupled to exciter windings disposed adjacent the air gap. Power from air gap harmonics, including air gap slot harmonics induce current in the exciter windings, which is rectified and supplied to the rotor field windings. In operation, a desired current level in the rotor field windings can be achieved through control of the DC power supply or superposition of harmonics into the stator winding current which induces the prescribed current in exciter windings.

Systems and methods concerning exciterless synchronous machines

One embodiment is a unique Vernier machine comprising a rotor and a stator. The rotor comprises a back portion and a plurality of permanent magnets. The stator comprises a plurality of ferromagnetic arm structures, a plurality of ferromagnetic pole structures extending from each of the ferromagnetic arm structures in a direction toward the permanent magnets, and a plurality of conductive windings disposed about respective ones of the plurality of ferromagnetic arm structures. The ferromagnetic pole structures are structured to collect magnetic flux from the permanent magnets. The ferromagnetic pole structures of each of said ferromagnetic arm structures are spaced apart from one another according to a non-uniform pattern such that the ferromagnetic pole structures of a given ferromagnetic arm structure have substantially the same angular position relative to the permanent magnets radially opposite from the ferromagnetic pole structures of the given ferromagnetic arm structure.

Electro-dynamic machine, system and method

Resonant converters with variable inductor

One exemplary embodiment is method of operating an electrically excited synchronous machine (EESM) system. The system includes a converter operatively coupled with one or more stator windings, an exciter operatively coupled with one or more field windings, a controller operatively coupled with the converter and the exciter, and a power supply operatively coupled with the converter and the exciter. The controller determines whether a power supply fault condition exists and whether EESM system is operating in a motor mode or a generator mode. If the power supply fault condition exists and the EESM system is operating in the motor mode, entering one of a motor ride through control mode and a motor controlled braking control mode If the power supply fault condition exists and the EESM system is operating in the generator mode, entering one of a generator ride through control mode and a generator controlled braking control mode.

Control of electrically excited synchronous machine drives for ride through and controlled braking operations

Technologies for reducing peak fault output current in a DC power generation system include a generator having a reduced damper winding and a controller to control a rectifier array to generate a DC power output. In some embodiments, the generator may have no damper windings, may have damper windings including a reduced number of damper bars, and/or may have damper windings having separated end ring mounts for each damper bar. The controller is configured to control the rectifier array so as to reduce oscillations of the DC output that may be due to the reduced damper windings. To do so, the controller is configured to generate the control signal based on an oscillation component of the DC power output. For example, the controller may generate an oscillation correction signal based on the DC power output and adjust a firing angle set point of the rectifier array based on the oscillation correction signal.

Growing community of inventors

Apex, NC, United States of America

Wen Ouyang