Electromagnetic torque , Electrical Engineering

Assignment Help:

Electromagnetic torque 

The torque is given by the force on the armature winding multiplied by its radius. Force on a conductor in magnetic field B is: 

F=B.I.L

so, T=B.I.L.R

The torque opposes the mechanical rotation of the rotor and so the mechanical torque turning the generator must do work against the electromagnetic torque in order to generate the voltage (and current) supplied to the electrical load connected to the generator. Therefore energy conversion occurs from mechanical energy to electrical energy.The flux density B webers/m  can be expressed in terms of the flux per pole, φ,  to give a relation between the electromagnetic torque to be overcome and current produced.

T=Cm.Ø.Ia

C=machine constant

The equivalent circuit representation of an electrical generator is:

 

 

478_Electromagnetic torque.png

 

The generator itself provides the source tosupply the field current I . Residualmagnetism will provide a small generatedcurrent at first that then builds up as thefield current grows, producing moregenerated current, etc. [NB leaving analternator open circuit will cause thevoltage to build up to the point wherediodes used to rectify the output voltagecan be damaged. Never operate an alternator without an electrical load connected. The output voltage is slightly less than the generated voltage due to the volt drop across the armature winding resistance when current flows. The arrangement of connecting the field winding in parallel with the armature is known as a shunt connected machine. The alternative is to connect the field winding in series with the armature, in which case it as known as a series connected machine.

Reversibility principle of electric machines

An electric machine can be operated as a generator or motor depending on the operation conditions. This is known as the reversibility principle of electric machines. For example, if the generator above is supplied from an electrical source, it will operate as a motor

 

 


Related Discussions:- Electromagnetic torque

Satellite Communication, ubmission Deadline: Wednesday, July 7, 2021 Assign...

ubmission Deadline: Wednesday, July 7, 2021 Assignment 2 EE5543 - Satellite Communication Question 1: MEASAT-1 is located at 91.5 o E and operating at the base frequency of 10.982

What is polymerised resultant of phenol and formaldehyde, Phenol and Formal...

Phenol and Formaldehyde are polymerised to a resultant product known as (A) PVC.                                  (B) bakelite. (C)  Polyester.                        (D)

Compute the capacitance per unit length, Write a program implementing the c...

Write a program implementing the conjugate gradient method (un-preconditioned). Solve the matrix equation corresponding to a finite difference node-spacing, h = 0.02m in x and y di

What is the use of latch signal on the ad0-ad15 bus, What is the  use of l...

What is the  use of latch signal on the AD0-AD15 bus in an 8086 system? Latch signal is used to load the data those are fetched from memory to bus.

Clipper, how to write kvl equation in series clipper circuit without any ba...

how to write kvl equation in series clipper circuit without any battery

Explain the basic concepts in memory interfacing, Explain the Basic concept...

Explain the Basic concepts in memory interfacing The primary function of memory interfacing is that the microprocessor should be able to read from and write into a given regist

What is message demodulation, Q. What is Message Demodulation? The majo...

Q. What is Message Demodulation? The major advantage of the conventional (standard) DSB AMsignal transmission is the ease with which the signal can be demodulated. Themessage s

Calculate the actual frequency of circuit, (a) The circuit of Figure 1 repr...

(a) The circuit of Figure 1 represents an amplifier-speaker connection. The filter is a low pass filter which is connected to the woofer. The filter is a -network. (i) Design a

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