Equivalent circuit of a polyphase induction machine, Electrical Engineering

Assignment Help:

Equivalent Circuit of a Polyphase Induction Machine

The inductionmachinemay be regarded as a generalized transformer inwhich energy is converted and electric power is transferred between stator and rotor, along with a change of frequency and a flow of mechanical power. At standstill, however, the machine acts as a simple transformer with an air gap and a short-circuited secondary winding. The frequency of the rotor-induced emf is the same as the stator frequency at standstill. At any value of the slip under balanced steady-state operation, the rotor current reacts on the statorwinding at the stator frequency because the rotating magnetic fields caused by the stator and rotor are stationary with respect to each other.

328_Equivalent Circuit of a Polyphase Induction Machine.png

The induction machine may thus be viewed as a transformer with an air gap and variable resistance in the secondary; the stator of the induction machine corresponds to the transformer primary, and the rotor corresponds to the secondary. For analysis of the balanced steady state, it is sufficient to proceed on a per-phase basis with some phasor concepts; so we will now develop an equivalent circuit on a per-phase basis. Only machines with symmetrical polyphase windings excited by balanced polyphase voltages are considered. As in other discussions of polyphase devices, let us think of three-phase machines as wye-connected, so that currents are always line values and voltages are always line-to-neutral values (on a per-phase basis).

The resultant air-gap flux is produced by the combined mmfs of the stator and rotor currents. For the sake of conceptual and analytical convenience, the total flux is divided into a mutual flux (linking both the stator and the rotor) and leakage fluxes, represented by appropriate reactances.


Related Discussions:- Equivalent circuit of a polyphase induction machine

Control bus -bus organisation, Control  Bus The control  bus comprises...

Control  Bus The control  bus comprises of various  single  lines that carry  various  control  signals for synchronizing  various devices  and performing different task. The m

Short note on armature reaction., Armature Reaction in DC Generator:  Arma...

Armature Reaction in DC Generator:  Armature reaction is the effect of magnetic flux set up by armature current upon the distribution of flux under the main poles.

Prepaid metering, Prepaid Metering Prepaid metering is the state of ar...

Prepaid Metering Prepaid metering is the state of art for single and three-phase although current metering, and should be implemented through utilities desirous of protecting

Mov instruction, MOV Instruction Op code  format  of MOV  instruction i...

MOV Instruction Op code  format  of MOV  instruction is as follows : Replace the  codes of destination register and source  register with code of  required  register from.

Controls and system, transfer function of Lube Oil Cooler Temperature

transfer function of Lube Oil Cooler Temperature

Explain the meaning of duality in boolean algebra?, Explain the Meaning of ...

Explain the Meaning of Duality in Boolean Algebra? Any algebraic equality that derived from the axioms of the Boolean algebra remains true when the operators OR and AND are in

Find the charge flowing and the number of electrons, Q. A current i(t) = 20...

Q. A current i(t) = 20 cos(2π × 60)t A fows through a wire. Find the charge flowing, and the number of electrons per second that are passing some point in the wire.

What is cd-rom, Compact Disc - Read Only Memory. A CD-ROM is any compact di...

Compact Disc - Read Only Memory. A CD-ROM is any compact disc which having computer data. These discs can store enormous amounts of data (up to 640 megabytes). If there is a large

Ac-dc voltages , To do the basic laboratory experiments related to the elec...

To do the basic laboratory experiments related to the electrical engineering course, students need to have some basic understanding about the measuring tools, apparatus, components

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd