An induction generator is disclosed wherein both the stator and rotor windings are utilized to generate power with the three phase winding of the stator and rotor each connected in parallel with a delta connected capacitive network connected therebetween. The electrical output may thus be increased by a factor of four over a conventional generator of the same size.
An asynchronous alternating current motor/generator having an armature winding which includes interspersed energy coils and reflux coils which are electrically and inductively isolated from each other, but which are paramutually inductively coupled through the rotor. Each reflux coil is positioned at 90 electrical degrees to the adjacent energy coil and is tuned to minimize the inductive reactance of the motor/generator.
A sationary rotatable anode (42) of an x-ray tube (10) is electrically connected to a high speed starter (24). The starter (24) includes an inductive rotor (44) connected to the anode (42), a main stator winding (50) and an auxiliary stator winding (52). The rotor (44) is driven by a power drive circuit (26) which is part of the starter (24). A main capacitor (64) is placed in series with the main winding for reducing its inductance. An auxiliary capacitor (66) is placed in series with the auxiliary winding for maintaining a selective impedence. A control circuit (90) is included in the starter (24) to control the main current and auxiliary current so that as the rotation of the rotor (44) increases, the control circuit (90) lowers the frequency of the main current and the auxiliary current passing to the main and auxiliary windings.
There is provided a generator system for internal combustion engines, which can produce power efficiently at all times irrespective of the engine speed even for use in an internal combustion engine operated at variable speeds such as a vehicle engine. An AC generator electronic control unit (ACG.ECU) 3 determines a rotation speed N2 of a rotating electromagnetic field to be generated by a rotor 1R based on a mechanical rotation speed N1 of the rotor 1R in an alternator 1 such that the relative speed N of the rotating magnetic field to a stator 1S agrees with the maximum efficiency speed of rotation Nx. Then the ACG.ECU 3 sends the determined value to a rotating electromagnetic field controller 2a. The rotating electromagnetic field controller 2a controls phases of AC power to be supplied to a three-phase coil 11 of the rotor 1R to generate a rotating electromagnetic field with the rotation speed N2.
A method for enhancing the operation of an electrical power supply includes selecting a prime mover having a chosen power rating. An induction motor having a first power rating at a rated speed and a second power rating at an overspeed is chosen. The overspeed may be at least about 10%, or at least about 25%, 50%, 75%, 10 to 300%, 25 to 300%, or 50 to 100%, greater than the rated speed. The induction motor may be chosen so that the second power rating is substantially the same as the chosen power rating of the prime mover. The induction motor is driven by the prime mover so that the induction motor acts as an induction generator. The system may also comprise a control module to monitor the performance of the power supply and to provide a throttle control signal in response to a control parameter signal. A circuit input of a phase shift circuit may be connected to a generator output. A converter input of an AC to DC converter may be connected to a circuit output of the phase shift circuit. A reservoir input of an energy reservoir may be connected to a converter output of the AC to DC converter.
An induction generator having one or more energy windings and one or more auxiliary windings where the auxiliary windings have fixed and switched capacitors which are used to control the induction generator output under variable load conditions. The auxiliary windings are electrically and magnetically isolated from the energy windings. The fixed capacitors are used under minimum load condition and the switched capacitors added in response to controls signals. The control signals are determined by analyzing the load voltage and current and the voltage across the particular capacitor being added. The induction generator is included in systems where the generator is rotationally driven by an engine and which couples the energy windings to a power grid and/or to a variable load. The engine may also employ a controller that receives the load current and voltage signals to determine engine speed.
