I am wondering why some few people gave a thump down for this video? There is nothing not to be liked in any of the contents. All difficult concept have been very simply explained. The world is a better place because of teachers like this man.
Because i've seen it on the comments. In the case of DC shunt motors , the connection is parallel , thus the current drawn from the winding of the electromagnet (the Rf resistance) is fixed everytime. That means that the Φ has also a fixed value each time and that's very positive compared to the dc motors where the winding of the electromagnet is in series with the Ea and Ra. So in order to procede , the voltage at the branch of the rotor is always the same and actually , because there is no counter torque at the end shaft of the motor , (the only counter torque that actually exists is the shear stresses from the medium that the shuft is being put in) , the whole voltage is being absorbed by the Back EMF due to Faraday's Law. If that condition exists , then why does it spin since there is no current and torque? The motor actually goes through intermittent periods of zero current (or let's better say , very low current that produces torque that its not enough to equal the moment of inertia and the friction of the shaft ) and as a consequence it falls back in speed. Then the rotational speed falls back and current goes up again and the torque goes up , so as the angular acceleration . So actually its like it has reached a datum where it goes back and forth . Of course the changes are so little that cannot be understood. Please feel free to discuss or even reject my point.
hello sir, i like your videos very much, you are a very good tutor, sir, i have a doubt here, in this numerical on the starting point after the equivalent circuit of the motor, while applying the equations: you have taken E=k(fi)N in place of K(fi)(Omega) and Omega = 2(pie)N/60 ???, but E=k(fi)(omega) so i need to ask that and Thank you for such wonderful and knowledgeable videos.
@@ElectricalisEasy Thank you for your response Sir, it is a great effort from your side Sir, In this video, starting from 3:06 where you have taken the value of E=K(fi)n in place of E=K(fi)(omega) and Sir, you have further continued to take the value of E as K(fi)n where n represents the speed of motor while Omega represents angular speed and Omega=2(pie)N/60, so the question is why you have taken N in place of Omega?? That's it sir and i am going through all your videos and it is very knowledgeable for me, i am gaining a good confidence on the subject, Thanks a lot Sir.
@@ElectricalisEasy Thank you again for such a quick and disciplined response, you are right Sir, the rest of the numerical is correct as on 4:20 on this video, Ea at 100 and Ea at no load gets divided to have a ratio of N at 100 and N at no load, so the problem solves there, but i got confused, at that time, whether we have to take E=K(fi)(omega) or E=K(fi)(N) on such numerical, but as you said it is a proportional symbol, everything is clear now. I am going through your every videos as it is very knowledgeable and i am gaining a good concept on this subject, Thank you very much Sir and please continue to have such videos for students like us is a boon. And i appreciate for your great effort, thank you Sir for everything.
6:34 How armature current can be zero when the rotor is moving at 1200 revolutions per minute? Without current the armature cannot have an induced torque.
and it is a no load case, in that case the current flowing through the armature is very less, so maybe that is why they took that assumption, bcz as you can see the load currents are quite high in the problem, so any error due to this assumption will be very less...
I am wondering why some few people gave a thump down for this video? There is nothing not to be liked in any of the contents. All difficult concept have been very simply explained. The world is a better place because of teachers like this man.
thanks for making a challenging topic very easy
Because i've seen it on the comments. In the case of DC shunt motors , the connection is parallel , thus the current drawn from the winding of the electromagnet (the Rf resistance) is fixed everytime. That means that the Φ has also a fixed value each time and that's very positive compared to the dc motors where the winding of the electromagnet is in series with the Ea and Ra. So in order to procede , the voltage at the branch of the rotor is always the same and actually , because there is no counter torque at the end shaft of the motor , (the only counter torque that actually exists is the shear stresses from the medium that the shuft is being put in) , the whole voltage is being absorbed by the Back EMF due to Faraday's Law. If that condition exists , then why does it spin since there is no current and torque? The motor actually goes through intermittent periods of zero current (or let's better say , very low current that produces torque that its not enough to equal the moment of inertia and the friction of the shaft ) and as a consequence it falls back in speed. Then the rotational speed falls back and current goes up again and the torque goes up , so as the angular acceleration . So actually its like it has reached a datum where it goes back and forth . Of course the changes are so little that cannot be understood. Please feel free to discuss or even reject my point.
thank you sir .
from sri lanka
hello sir, i like your videos very much, you are a very good tutor, sir, i have a doubt here, in this numerical on the starting point after the equivalent circuit of the motor, while applying the equations: you have taken E=k(fi)N in place of K(fi)(Omega) and Omega = 2(pie)N/60 ???, but E=k(fi)(omega) so i need to ask that and Thank you for such wonderful and knowledgeable videos.
Kindly give me the time stamp of the video where you faced the doubt...
@@ElectricalisEasy Thank you for your response Sir, it is a great effort from your side Sir, In this video, starting from 3:06 where you have taken the value of E=K(fi)n in place of E=K(fi)(omega) and Sir, you have further continued to take the value of E as K(fi)n where n represents the speed of motor while Omega represents angular speed and Omega=2(pie)N/60, so the question is why you have taken N in place of Omega?? That's it sir and i am going through all your videos and it is very knowledgeable for me, i am gaining a good confidence on the subject, Thanks a lot Sir.
Yes you are correct, I should have put the proportional symbol..it was a small typo..but the rest of the numerical is correct...
@@ElectricalisEasy Thank you again for such a quick and disciplined response, you are right Sir, the rest of the numerical is correct as on 4:20 on this video, Ea at 100 and Ea at no load gets divided to have a ratio of N at 100 and N at no load, so the problem solves there, but i got confused, at that time, whether we have to take E=K(fi)(omega) or E=K(fi)(N) on such numerical, but as you said it is a proportional symbol, everything is clear now. I am going through your every videos as it is very knowledgeable and i am gaining a good concept on this subject, Thank you very much Sir and please continue to have such videos for students like us is a boon. And i appreciate for your great effort, thank you Sir for everything.
Thanks a lot sir🙏🏻
If no load current is zero, how the motor rotate sir? Please clarify
Excellent sir
13.40
I am getting another value of every torque equations. Can you explain the calculations? At least one. Torque (100,200,300)=?
6:34
How armature current can be zero when the rotor is moving at 1200 revolutions per minute? Without current the armature cannot have an induced torque.
That’s an assumption given in the numerical itself....it’s just for the numerical case...
and it is a no load case, in that case the current flowing through the armature is very less, so maybe that is why they took that assumption, bcz as you can see the load currents are quite high in the problem, so any error due to this assumption will be very less...
Varun D Nair but ia and il is approximately zero what about field current? İt can not be 5A
@@alperkayabas4563 good question
Sir after completing machines will you go to other subjects also
Yes but have not decided now, what subject to be tackled.
Thanks alot, these videos are very helpful and clears lot of concepts.
Thank you and please don't forget to share the videos with people who might benefit from these videos.. #sharetheknowledgd
ur tutorials are very useful for placement placement preparation... pleace add videos for power electronics too... tq sir
which software do you use for making these notes?
It's windows journal with a digitizer
Why Ia is 0 at no load?
It's already answered in the comments look carefully 😉
In problem 1