Why DC Currents are not used in transformer?
Answers were Sorted based on User's Feedback
Answer / shiva
the transformer Works on variable flux(A.c. flux, rms value
is const) if we give dc input the flux generated is
stationary and cannot devolp the induced emf in primary(E1)
&secondary(E2)...so there is no opposition of current flow
in primary & Secondary(since E1,E2=0).....there fore high
currennt passes through windings ...so that wdg may damage
to such high currents...
Another way of explination
transformer core material works on some const magnetic flux
density..in some range... but if give dc in put its
frequency is zero. So
B=V/F ===)B=v/0 ===)B~~ infinate value...requred such
material is not possible practically
Is This Answer Correct ? | 4 Yes | 1 No |
Answer / anurag sankar sengupta
transformer mainly works on the principle of varying flux and minimum reluctance path.
now when we connect the source to a dc supply the magnetic flux linking the core become stable to a value. so the transformer will gain some amount of heat and be burned if the voltage becomes hi gher than the normal.
Is This Answer Correct ? | 4 Yes | 2 No |
Answer / jaheerabbas
in transformer primary and secondary windings are behaves
like inductor in initial stage (t=0)sec, inductor impedance
formula is 2*pi*F*L, so F=0 means DC then no inductor
effect,no inductor effect then no Flux,no EMF nothing....so
only we are not using DC signal in transformer
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / pradyumna chandra panda
In transformer there is verry small resistance in primary winding it stand with ac supply because itself an inductive load ( leg the current). but there is no possible of legging current in dc supplly if we give it in transformer the primary winding will be burn out due to small resistance of primary winding and no emf will induced in secondary winding due to failure of mutual induction.where flux linkage is not possible.
Is This Answer Correct ? | 2 Yes | 1 No |
Can u explain : what is supply for train (whether a,c or d.c ).I know that supply is 25000v a.c .But there is rumour that supply is D.C. And also explain how lights and fans inside the trains are working ,and what type of motors are used in trains whether D.C motors or induction motors .If d.c motor, how it gets supply.If traction motors are used then what are traction motors and its functions and how it differs from other motors and also explain about locomotive . please reply..............
How to select transmission line type (i.e. 11kv or 33kv) for new established industries
why transformer ratings in kva?
99 Answers Bhel, College School Exams Tests, DOW, Emco, Esab, GE, KCP, PGCVL, Sodexo, TCS, vtps, Wipro,
15hp motor wound by 0.9mm & 0.95mm magnet wire. at no load test it draw 4.2A current. Another motor with same condition draw 9.2A current. How can that occur? pls help
Q-1 what are the structural and operational difference between a distribution and a power transformer? Q-2 what is skew in motors? Q-3 draw equivalent circuit of transformer Q-4 explain with phasors how pf is improved with loading in induction motors Q-5 DIFFERENT METHODS OF CABLE LAYING(interviewer asked if i heard new chemical based earthing system next) Q-6 pi model of medium length trans line Q-7 v/f control?why Q-8 vacuum circuit breaker operates in?
what are fluorescent lamps (fluorescent fixtures) & what are incandescen lamps (incandescents fixtures) ? differences between these two ?
How i measured Bus bars weight without wighting ?
what is 400kv doble circuit quadpole tower?
what do you know about electrical
whow we find out dc motor field aur armature resistance
I'm generating a pulse of 3V with frequency 80Hz (12.5ms time period) and pulse duration 0.125ms and feeding it to a transformer since i want the pulse to get amplified around 60V. At the output amplification s happening but the pulse is changed to a spike, can you tell me what could be the reason? (an ordinary transformer 220V-12V stepdown transformer is reverse connected ie. now it is 12V-220V stepup and voltage amplification happens)
why should the lowest unit of a testing transformer ( cascaded transformer ) have higher power rating??