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Scherbius Drive
The Static Scherbius Drive provides the speed control of a wound rotor motor below synchronous speed An alternator is an Generator (device), electrical generator that converts mechanical energy to electrical energy in the form of alternating current. For reasons of cost and simplicity, most alternators use a rotating magnetic field with a stati .... The portion of rotor AC power is converted into DC by a diode bridge. This drive has the ability of flow the power both in the positive as well as the negative direction of the injected voltage. References Induction motors {{technology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wound Rotor Motor
A wound-rotor motor, also known as slip ring-rotor motor, is a type of induction motor where the rotor windings are connected through slip rings to external resistance. Adjusting the resistance allows control of the speed/torque characteristic of the motor. Wound-rotor motors can be started with low inrush current, by inserting high resistance into the rotor circuit; as the motor accelerates, the resistance can be decreased.Harold J. Herbein ''Rotating Machinery'', Rinehart Press, 1971, SBN 03-084675-7, pages 215-218 Compared to a squirrel-cage rotor, the rotor of the slip ring motor has more winding turns; the induced voltage is then higher, and the current lower, than for a squirrel-cage rotor. During the start-up a typical rotor has 3 poles connected to the slip ring. Each pole is wired in series with a variable power resistor. When the motor reaches full speed the rotor poles are switched to short circuit. During start-up the resistors reduce the field strength at the stato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synchronous Motor
A synchronous electric motor is an AC electric motor in which, at steady state, the rotation of the shaft is synchronized with the frequency of the supply current; the rotation period is exactly equal to an integral number of AC cycles. Synchronous motors contain multiphase AC electromagnets on the stator of the motor that create a magnetic field which rotates in time with the oscillations of the line current. The rotor with permanent magnets or electromagnets turns in step with the stator field at the same rate and as a result, provides the second synchronized rotating magnet field of any AC motor. A synchronous motor is termed ''doubly fed'' if it is supplied with independently excited multiphase AC electromagnets on both the rotor and stator. The synchronous motor and the induction motor are the most widely used types of AC motors. The difference between the two types is that the synchronous motor rotates at a rate locked to the line frequency since it does not rely on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
