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Electric Motor Characteristics

Electric Motor Characteristics: The machine and the load are the two components of an electro-mechanical energy-conversion system, and the Electric Motor Characteristics, generally, play a predominant part in the operating behavior of the complete system. In choosing an electric motor its speed-torque characteristic is needed to be known to a fair degree of accuracy and …

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Synchronous Generator Ratings and Loss Dissipation

Synchronous Generator Ratings and Loss Dissipation: The Synchronous Generator Ratings and Loss Dissipation is its operating voltage, frequency, speed and kVA/MVA output at a specified power factor. In case of motors the output rating is given in kW (older practice was to specify the rated output in horse-power (1 hp = 746 W)). The dc …

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Principle of Induction Motor

Principle of Induction Motor | Torque Slip Characteristic: Principle of Induction Motor has not been introduced so far. Consider a cylindrical rotor machine with both the stator and rotor wound for three phases and identical number of poles as shown in Fig. 5.40. Assume initially the rotor winding to be open-circuited and let the stator …

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Torque in Round Rotor Synchronous Machine

Torque in Round Rotor Synchronous Machine: Torque in Round Rotor Synchronous Machine – When the stator and rotor windings of a machine both carry currents, they produce their own magnetic fields along their respective axes which are sinusoidally distributed along the air-gap. Torque results from the tendency of these two fields to align themselves. The …

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Rotating Magnetic Field

Rotating Magnetic Field: Rotating Magnetic Field – It was seen earlier that the sinusoidal current in any phase of an ac winding produces a pulsating mmf wave in space whose amplitude varies sinusoidally with time. The expression for the fundamental component of this mmf is given in Eq.(5.36). The harmonics of the mmf wave are …

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Sinusoidally Distributed Current Sheet Concept

Sinusoidally Distributed Current Sheet Concept: It was seen above that a distributed winding gives rise to a stepped mmf wave having a strong fundamental component which will be considered in machine modelling while all the harmonic components will be neglected (justification for the same has been advanced). Now the kind of space distribution of current …

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MMF of AC Distributed Winding

MMF of AC Distributed Winding: It has been seen earlier that the armature what-when-how.comof a practical machine has distributed winding wound for the same number of poles as the field winding. As the armature carries current, the resultant field of its current-carrying coils has the same number of poles as the field winding. Our approach …

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