Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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
Cm =machine constant
The equivalent circuit representation of an electrical generator is:
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 machinesAn 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
Q. What is Own-exchange routing? Distributed routing or own-exchange routing enables alternative routes to be chosen at intermediate nodes. Hence the strategy is capable of res
Figure shows the cross-section of an electrostatic problem with translational symmetry: a rectangular coaxial cable. The inner conductor is held at 10 volts and the outer conductor
In a certain chemical-processing plant, a liquid chemical is used in a manufacturing process. The chemical is stored in three different tanks. A level sensor in each tank produces
Q. The equations for a two-port network are given by V 1 = z 11 I 1 + z 12 I 2 0 = z 21 I 1 + (z 22 + Z L )I 2 V 2 = - I 2 Z L (a) Satisfying the equations, dev
A relay is essentially an electromechanical switch that opens and closes electrical contacts. A simplified relay is represented in Figure. It is required to keep the fenomagnetic p
(a) Find the Fourier series for the square wave shown in Figure(a). (b) Let a voltage source having the waveform of part (a) with a peak value of 100 V and a frequency of 10 Hz
What is coupling? Explain the types of coupling
Increase in HT and LT Ratio It is well known that for high HT/LT ratio, the losses will be low. The losses for a given quantum of power supplied through a line are inversely p
Q. A50-kW, 230-Vcompound generator has the following data: armature-circuit resistance 0.05 , series-field circuit resistance 0.05 , and shunt- field circuit resistance 125 . As
After I complete my diploma how I get a job in goverment
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd