Abstract: Ceramic adhesive is applied inside the slots of an electric machine squirrel cage rotor prior to casting or insertion of rotor conductors. This heat-resistant insulation provides superior electrical insulation that is also mechanically rugged, thus enabling casting of squirrel cage rotors by die or cost-effective consumable pattern casting. The consumable pattern cast copper rotors are electrically well insulated, thus minimizing rotor losses. The ceramic insulation in cast rotors enables longer conductors to be cast by thermally insulating the molten metal from the cooler laminations. The ceramic insulation in fabricated rotors withstands the high temperatures of end ring attachment.

Abstract: Ceramic adhesive is applied inside the slots of an electric machine squirrel cage rotor prior to casting or insertion of rotor conductors. This heat-resistant insulation provides superior electrical insulation that is also mechanically rugged, thus enabling casting of squirrel cage rotors by die or cost-effective consumable pattern casting. The consumable pattern cast copper rotors are electrically well insulated, thus minimizing rotor losses. The ceramic insulation in cast rotors enables longer conductors to be cast by thermally insulating the molten metal from the cooler laminations. The ceramic insulation in fabricated rotors withstands the high temperatures of end ring attachment.

Abstract: Ceramic adhesive is applied inside the slots of an electric machine squirrel cage rotor prior to casting or insertion of rotor conductors. This heat-resistant insulation provides superior electrical insulation that is also mechanically rugged, thus enabling casting of squirrel cage rotors by die or cost-effective consumable pattern casting. The consumable pattern cast copper rotors are electrically well insulated, thus minimizing rotor losses. The ceramic insulation in cast rotors enables longer conductors to be cast by thermally insulating the molten metal from the cooler laminations. The ceramic insulation in fabricated rotors withstands the high temperatures of end ring attachment.

Abstract: Processor-based field oriented control for brushless doubly-fed induction machine having first and second polyphase stator windings is programmed to operate the machine in various modes, as a motor or a generator, with bumpless switching between operating modes. An electronic power converter controls a current supplied to the first stator winding to control the torque of the machine, with the second stator winding selectively connected to an AC line. Stationary coordinates for in-phase and quadrature current commands are coordinate transformed using a voltage vector for voltage induced on the first polyphase stator winding to control current in the first stator winding, with or without a position sensor. The electronic power converter controls the voltage supplied to the first stator for generating, with the second stator selectively connected to a load. The machine can also be controlled to operate as a singly-fed motor at lower speeds, with the second stator winding shorted.

Abstract: Processor-based field oriented control for brushless doubly-fed induction machine having first and second polyphase stator windings is programmed to operate the machine in various modes, as a motor or a generator, with bumpless switching between operating modes. An electronic power converter controls a current supplied to the first stator winding to control the torque of the machine, with the second stator winding selectively connected to an AC line. Stationary coordinates for in-phase and quadrature current commands are coordinate transformed using a voltage vector for voltage induced on the first polyphase stator winding to control current in the first stator winding, with or without a position sensor. The electronic power converter controls the voltage supplied to the first stator for generating, with the second stator selectively connected to a load. The machine can also be controlled to operate as a singly-fed motor at lower speeds, with the second stator winding shorted.

Abstract: A brushless doubly-fed induction machine comprising dual cage rotors, suitable for use in generator applications requiring a fixed-frequency electrical output that is independent of a rotational speed at which the machine is driven or motor applications requiring limited variable speed operation when connected to an AC mains. Various embodiments are disclosed, but each includes a stator frame in which first and second annular stators are mounted spaced-apart, end-to-end along a common axis. Each annular stator includes a core wound with polyphase distributed windings defining a plurality of poles. First and second rotors, mounted on a common shaft, are disposed within the first and second annular stators, respectively. Each of the rotors includes a laminated core having a plurality of longitudinally-extending slots defined around a periphery thereof, and at least one conductor is disposed in each slot.