All these comments criticising this video is somewhat right but as the ma'am said there is a catch so she meant that there is an exception and it is giving pulse D.C. to a pulse transformer and one more point to all my commentators - yes a pulse D.C exists . if u don't believe then go and google it. so we conclude that- 1. heading of this video is totally correct 2. Information given in this video is totally true because if it is wrong , then i would not be able to charge my mobile in train and could not comment. 3. Dear cameraman please focus on the circuits made by ma'am rather than her face because we are here to learn something from her not to see her face. 4. ma'am keep uploading ur videos we are here to learn and grow.
Dc is dc because it's not pulsating They using converters U are directly ignoring basics DC generates a standard magnetic field Some may be criticize because they know dc convert. Transformer to a magnet But still some people there don't understand few things they may thought dc can run transformer They may lose marks bcoz of these Just my point of view
I can also take the output of a Variable Frequency Drive (VFD) and feed it into an induction transformer and have it work the same. The output of a VFD is a Pulse Width Modulated DC voltage, that can be made to imitate an AC signal.
Dont say it is DC...you may call it as pulsed DC or Half sine wave which has frequency component in it. Hence, it still obeys faraday's law (time varying flux requires frequency component in it)....Pure DC does not have frequency component, will not work and burn after some time. Use correct terms in your title.
nice explanation........cell phone charger is basically a "SMPS".after rectification of "AC to DC" the DC is fed to a high frequency switch which works by "PWM TECHNIQUE" after this it is connected to a "transformer" and the out of transformer is again connected to next stage rectifier THERE WE GET 5V ...........There should be a rectifier unless its "HIGH FREQUENCY SWITCHED SUPPLY" ...
Dear sir/ mam I got some question in my mind .. i tried every where search on net .. but dint get.. plz help Q1) how to find any capacitor value of any single phase motor with the help of Given data *winding value resistance Voltage RLA current SPEED MULTY OR SINGLE RPM WATT Q2) And also how to knw abt watts /HP / KW ... with help of motor resistance any single phase or 3 phase Because on field we face lott of issue with Motor name plate... missing
connect motor to supply, if there is any capacitor on yhe motor than connect to 1 phase otherwise in case of 3 phase motor connect to 440 volt supply and measure the current of motor in case of three phase motor current will be ~1.5 times of rated HP of motor. Now you can calculate the HP of motor without its nameplate
Who in this entire multiverse taught you that an pulsating signal is DC. And if we could make a transformer which is working on DC why aren't we not using in transmitting electrical energy hence DC has less power loss comparing AC.
AC power can be stepped up or down by windings to limit transmission loses due to resistance loses in the wire by Power Lose = Voltage*Current = Wire resistance * (Current)^2. This is why long transmission lines are high voltage.
@@antonsv2195 You are exactly correct but that lady in that video tells DC power can be used to make a transformer work. If they could step up and step down DC power everyone would be gone for DC power.
Pulsating waveforms that are unipolar (of either only positive or negative polarity) usually are treated as dc signals. The video clearly states that transformers won't work with steady DC but only pulsating dc signals. Also HVDC transmission is a very real thing. We can increase or decrease dc voltages pretty conveniently using power electronic converters but are usually restricted to low power applications, typically from around a few watts in your cellphone chargers to about 100kW in electric vehicle fast chargers.
When you rectified AC u get pulsating DC....it works on specially designed pulse transformer. She is taking abt pulsating transformer but for views she has given wrong TITLE.
Please do not pollute the fundamental principles of physics by saying transformers will work on DC. Leave the topic of pulse transformers for power engineers only. These types of things occur when engineers are recruited as teachers where the fundamental concept gets lost and students gets confused.
you are absolutely wrong sir. we have to teach him fundamental principle as well as this principle. then only stuent will start thinking and approach the teacher and start asking the doubts or start searching in internet.
I am very happy that you teached very nice practical concept which is very less explained in day today classes. You explain the pwm hft concept of smps.great ma'am.
Here if you applied dc.. (1). Ideal transformer ( only coil) (2). Practical Transformer ( coil with resistance). (1).Then Vl = L * di/dt =Vdc... From there we can calculate I(t) =( Vdc/L) * t... That means if we provide dc then current will increase and due to this the transformer core will go into deep saturation since flux is increasing. But constant voltage will induced in primary side as well as secondary side. (2). For practical case if we do transient analysis of RL ckt. then we will get I(t) =( Vdc/L) *(1-e^t/tau)... During transient period it will give time varrying induced emf in primary nd secondary side. But at steady state there will be no induced emf as flux become constant at steady state. So... Ideal transformer induced voltage under DC condition will be constant voltage but practical transformer at steady state there will be no induced emf. In case of pulse transformer whatever discusses it is right.
Thank you for well scripted lecture.... we need to question the existence of all rules and terminologies......these rules r being made to question the boundaries .... all d best keep up the good teaching spirits
"we need to question the existence of all rules" There is no WE. Be sure to question THIS presentation while you are at it. Maybe there's an answer among the questions.
Dear mam, I want to note that winding will be only damaged when you give rated dc to primary winding. If this voltage is less than rated dc, windings can sustain that voltage.
DC voltage less that rated can still damage the transformer. The dc voltage needs to be very low such that only rated current flows though the transformer. Such a dc voltage may be in the range of only a few volts or even tens of volts for most transformers.
In presence of dc current the inductive windings in primary coil is treated as short circuit More current will flow more power in form of heat will dissipate and boom your transformer is on fire
Dear Firstly even the positive pulse waveform cannot be applied directly to the transformer, else transformer will saturate. All that is required for the transformer is the volt sec balance should satisfy across the primary winding, i.e. average value should be zero , so that flux resetting happens. and why you shown transformer output as DC, there is a converter phase in between which does that. Please be precise while delivering such lectures.
In charger circuit transformer is used for isolation the voltage is control is changed due to changing Duty cycle of transistor or scr Input given to transformer is pulsating dc
Every transformer works on time varying power supply. DC is DC don't try to confuse with pulsed DC. Pulsed DC is combination of AC + DC , in case transformer is working on Time varying signal not DC. Remember the fundamentals Faraday laws
Dc voltage applied to a transformer will initially make it an open circuit and later on as the time progresses the current develops and increases gradually as per time constant L/R and attains it's maximum value after certain time and then it's behaves as short circuit and draws heavy current from supply mains and get damaged. In pulsed Dc the time constant of the circuit is making the delay in current increment rate and once the pulse downs to zero the decrement in current starts this pulses are making the current not to attain it's maximum value and time constant of the circuits is making gradual increase in its value.
Mam i think that train explanation is not exactly correct...i learnt that when train is running at desired limit range speed of generator where PM is actually train wheels..the supply we get is directly from generator...but when train runs very slow or very high speed..we cut the generator n now power is supplied by backup battery unit..which chnges dc to ac using inverter and finally we get ac as output only in either case... In general case we get supply from battery bank only thats y its written 110V DC...plz correct me if i m wrong... Thank u
All these comments criticising this video is somewhat right but as the ma'am said there is a catch so she meant that there is an exception and it is giving pulse D.C. to a pulse transformer and one more point to all my commentators - yes a pulse D.C exists . if u don't believe then go and google it. so we conclude that-
1. heading of this video is totally correct
2. Information given in this video is totally true because if it is wrong , then i would not be able to charge my mobile in train and could not comment.
3. Dear cameraman please focus on the circuits made by ma'am rather than her face because we are here to learn something from her not to see her face.
4. ma'am keep uploading ur videos we are here to learn and grow.
nikhil singh
@@dharmrajpatel4057 yaa bro?
ruclips.net/video/WNRzU5DLA0I/видео.html
www.quora.com/Charging-points-in-Indian-trains-are-110V-D-C-but-my-mobile-charger-and-laptop-charger-needs-110-V-A-C-Still-both-the-chargers-are-working-properly-How-is-it-possible
Dc is dc because it's not pulsating
They using converters
U are directly ignoring basics
DC generates a standard magnetic field
Some may be criticize because they know dc convert. Transformer to a magnet
But still some people there don't understand few things they may thought dc can run transformer
They may lose marks bcoz of these
Just my point of view
her friendly up beat teaching style is very refreshing i dont think i would start to drift off to sleep in her class
I understand perfectly thanks lot this question confusing since from 3yrs when I travelling in train once again tq madam
Thank You So Much Ma'am I Got My Doubt Clarified Which Was A Doubt For Years ..
Very corect what you are saying - thanks for a corect course of electrical engineering
I can also take the output of a Variable Frequency Drive (VFD) and feed it into an induction transformer and have it work the same. The output of a VFD is a Pulse Width Modulated DC voltage, that can be made to imitate an AC signal.
Thanks for clearing my doubt, the video was very informative. And yes I'll not forget to mention that you got really beautiful smile.
Dont say it is DC...you may call it as pulsed DC or Half sine wave which has frequency component in it. Hence, it still obeys faraday's law (time varying flux requires frequency component in it)....Pure DC does not have frequency component, will not work and burn after some time. Use correct terms in your title.
I think she is dumb. Who is she ? Teaching wrong information.
Fluctuating voltage*
Really, she has lack of practical knowledge.
So nice of you and for your kind information I tell you , this is not a dc it is a smooth dc or puls ok
We understand it English
Please more videos
Thanks a lot
Madam incomplete information is injurious to health .
Don't make fool to the students
Glt explanation diya he
Galat to Nahi kah shakte ,
Incomplete word better Hoga use karna
Way of teaching is good
Better use the word SMPS technology if u face this kind of question in interview
I like your teaching style
Please explain Telugu Aldo. It is useful to others like iti and diploma students.
nice explanation........cell phone charger is basically a "SMPS".after rectification of "AC to DC" the DC is fed to a high frequency switch which works by "PWM TECHNIQUE" after this it is connected to a "transformer" and the out of transformer is again connected to next stage rectifier THERE WE GET 5V ...........There should be a rectifier unless its "HIGH FREQUENCY SWITCHED SUPPLY" ...
Rectified dc given to high frequency switch(transistor or mosfet) and this output fed to transformer
the way of teaching and writing is excellent....
Nicely explain.....well done
ruclips.net/video/ygzss6mYlZs/видео.html
THANK YOU that was VERY well explained and makes SENSE! GREAT job!
Nice info mam..thanks ...nd ur looking so attractive during the teaching
Nice video mam. The intention u have to let us know such tricky questions is really great. Go ahead
Very interesting topic..I was really like this video
Ur voice is crystal clear.
Thank you mam...very well explained..bhaut dino se doubt tha..clear hogaya...🤗🤗
Thank you ma'am for sharing this
Dear sir/ mam
I got some question in my mind .. i tried every where search on net .. but dint get.. plz help
Q1) how to find any capacitor value of any single phase motor with the help of
Given data
*winding value resistance
Voltage
RLA current
SPEED MULTY OR SINGLE
RPM
WATT
Q2) And also how to knw abt watts /HP / KW ... with help of motor resistance any single phase or 3 phase
Because on field we face lott of issue with Motor name plate... missing
calculation is there for specific torque output. follow that type numerical
1 you can get from P.S. bhimra generalized theory of machine
connect motor to supply, if there is any capacitor on yhe motor than connect to 1 phase otherwise in case of 3 phase motor connect to 440 volt supply and measure the current of motor in case of three phase motor current will be ~1.5 times of rated HP of motor. Now you can calculate the HP of motor without its nameplate
Who in this entire multiverse taught you that an pulsating signal is DC. And if we could make a transformer which is working on DC why aren't we not using in transmitting electrical energy hence DC has less power loss comparing AC.
Nice questions
AC power can be stepped up or down by windings to limit transmission loses due to resistance loses in the wire by Power Lose = Voltage*Current = Wire resistance * (Current)^2.
This is why long transmission lines are high voltage.
@@antonsv2195 You are exactly correct but that lady in that video tells DC power can be used to make a transformer work. If they could step up and step down DC power everyone would be gone for DC power.
Pulsating waveforms that are unipolar (of either only positive or negative polarity) usually are treated as dc signals. The video clearly states that transformers won't work with steady DC but only pulsating dc signals. Also HVDC transmission is a very real thing. We can increase or decrease dc voltages pretty conveniently using power electronic converters but are usually restricted to low power applications, typically from around a few watts in your cellphone chargers to about 100kW in electric vehicle fast chargers.
When you rectified AC u get pulsating DC....it works on specially designed pulse transformer.
She is taking abt pulsating transformer but for views she has given wrong TITLE.
Today you clear the my doubts,thank you
Great video.....get good knowledge of the basic topics
I did not understand how the puls transformers works. The rest was very good. Thanks.
Fantastic inputs.
Your way of teaching is very good and ur smile omg ,i falling to you.
Please do not pollute the fundamental principles of physics by saying transformers will work on DC. Leave the topic of pulse transformers for power engineers only. These types of things occur when engineers are recruited as teachers where the fundamental concept gets lost and students gets confused.
she should have told about the SMPS.
you are absolutely wrong sir. we have to teach him fundamental principle as well as this principle. then only stuent will start thinking and approach the teacher and start asking the doubts or start searching in internet.
Before every conclusion.... There are a lot of wrong concept..
@@sadmadkab This shows how good you are at the subject. Donot put our students at shame in front of the world .
I am very happy that you teached very nice practical concept which is very less explained in day today classes. You explain the pwm hft concept of smps.great ma'am.
So Nice of you...
Here if you applied dc.. (1). Ideal transformer ( only coil) (2). Practical Transformer ( coil with resistance).
(1).Then Vl = L * di/dt =Vdc... From there we can calculate I(t) =( Vdc/L) * t... That means if we provide dc then current will increase and due to this the transformer core will go into deep saturation since flux is increasing. But constant voltage will induced in primary side as well as secondary side.
(2). For practical case if we do transient analysis of RL ckt. then we will get I(t) =( Vdc/L) *(1-e^t/tau)... During transient period it will give time varrying induced emf in primary nd secondary side. But at steady state there will be no induced emf as flux become constant at steady state.
So... Ideal transformer induced voltage under DC condition will be constant voltage but practical transformer at steady state there will be no induced emf.
In case of pulse transformer whatever discusses it is right.
Nicely explained
Thank you
Thanks mam . Way of explanation is very interesting.
Good explanation .
Excellent described.Thanks
Well explained... Keep sharing...
Very informative
👌👍👍
Thank you for well scripted lecture.... we need to question the existence of all rules and terminologies......these rules r being made to question the boundaries .... all d best keep up the good teaching spirits
"we need to question the existence of all rules"
There is no WE.
Be sure to question THIS presentation while you are at it.
Maybe there's an answer among the questions.
Nice explanation please make vedio on pulse DC transformer, Thanks.
Excellent explanation.
Dear mam,
I want to note that winding will be only damaged when you give rated dc to primary winding. If this voltage is less than rated dc, windings can sustain that voltage.
K N Rao jindabad
DC voltage less that rated can still damage the transformer. The dc voltage needs to be very low such that only rated current flows though the transformer. Such a dc voltage may be in the range of only a few volts or even tens of volts for most transformers.
In presence of dc current the inductive windings in primary coil is treated as short circuit
More current will flow more power in form of heat will dissipate and boom your transformer is on fire
It is also the case that DC will saturate the core and the AC component will cease going *through* the transformer.
Thanks, Mam.
It was really confusing question. Now i have clear concept about it.....
Thanks.its very useful.
Hi madam, nice info video, can u tell which pulse transformer is used in mobile charger. There are two type of pulse transformer is there.
Camera man,please don't shoot her face by zooming we can't see the back circuit diagram
Ull get short circuit ed if u see that
🤣🤣🤣
Good way to explain mem so plz continue to make complete series of electrical machines
Nice information ma'am
Thank you
Thank u for every thing this channel made me clear my Meo class 4
Really? What question surveyor asked??
What question surveyor asked? This video came yesterday only..??
It makes sense. I use dc brushed motor in series as pulse generator to connect transformer for powering up ac led bulb during emergency
Aap mujhe bahut pasand aaye accha video tha explain accha kiye,😍
Kuch samajh nahi aaya per sun kar bahut achha lga
Mam really mja aa gya plz aise topic post karte rhiyega
you have cleared my 15 years old question
zulfiquar ali .....મુ
Yours all of videos are very interesting, Shekhar sir also teach very good.
Dear....mam please explain about power factor
*Your video is right but your way of teaching is something needs more improvement.*
Dear Firstly even the positive pulse waveform cannot be applied directly to the transformer, else transformer will saturate. All that is required for the transformer is the volt sec balance should satisfy across the primary winding, i.e. average value should be zero , so that flux resetting happens. and why you shown transformer output as DC, there is a converter phase in between which does that. Please be precise while delivering such lectures.
Excellent...
Aripichav anna.
Pulse dc is not pure dc, it is different, pulse dc means mixed with dc
Have a look at this NCS thotakura shekar
But in our no where it is mentioned that it is dc voltage. It gets only 100-240V ac.
thumbs up for english title with english speaking video.
Great video. Thank you ma'am!
Nice vedio and very useful
ruclips.net/video/ygzss6mYlZs/видео.html
Beautifully explained...
Thank you very much ma'am
Thanks
Thank you
nice lecture..
Excellent video. I have a question to you Madam. Is the automotive ignition coil a pulse type transformer?
Bingo, you are absolutely correct 😍
That was a good work
Perfect👍
Ah!!❤️ Snehalika Maam!! Is love❤️😌😍😌
Thank You Honorable Madam..
Thanks a lot for this very much usefull information..
Interesting video madam..
Good teaching method...but how come the flux reversals is archived
In charger circuit transformer is used for isolation the voltage is control is changed due to changing
Duty cycle of transistor or scr
Input given to transformer is pulsating dc
Can we use thyristor for pulse dc??
u got a new subscriber here..
Very good voice and lecture delivery .... more practice before recording
I always watch your videos for the last almost 2 years but this is first time ever I'm doing comment on your upload!. Best wishes!
I like this video 👌
By using a crt u can check puls of output dc
Every transformer works on time varying power supply. DC is DC don't try to confuse with pulsed DC. Pulsed DC is combination of AC + DC , in case transformer is working on Time varying signal not DC. Remember the fundamentals Faraday laws
Dc voltage applied to a transformer will initially make it an open circuit and later on as the time progresses the current develops and increases gradually as per time constant L/R and attains it's maximum value after certain time and then it's behaves as short circuit and draws heavy current from supply mains and get damaged.
In pulsed Dc the time constant of the circuit is making the delay in current increment rate and once the pulse downs to zero the decrement in current starts this pulses are making the current not to attain it's maximum value and time constant of the circuits is making gradual increase in its value.
I hope you will replay mam
Wether output will be pulsating dc
Or continouse
Good explanation
Good content
I satrted watching this video with more curiosity nd end by telling its just a waste of time...
change your topic to "How transformer works on Pulsated DC".
may be she is talking about chopper transformer which is design for high frequency, and she called it pi-transformer.
Whether pulse and flyback transformers are same?
Thanx mam ... for this special session...
On special pulse transformer ....😎🤟
Superbbbb story
Thank you Ma'am
Nice explanation...
thanks a lot 👍👍👍👍🙏
Hey can you please explain why power dissipation may be considered in transistor for any project
Mam i think that train explanation is not exactly correct...i learnt that when train is running at desired limit range speed of generator where PM is actually train wheels..the supply we get is directly from generator...but when train runs very slow or very high speed..we cut the generator n now power is supplied by backup battery unit..which chnges dc to ac using inverter and finally we get ac as output only in either case...
In general case we get supply from battery bank only thats y its written 110V DC...plz correct me if i m wrong...
Thank u
would the dc output from transformer be harmonic free?