ELECTRICAL TECHNOLOGYElectricity is not a fun but easy to learn.
Prepared by, Mr. Vijay Balu RaskarCHAPTER NUMBER NAME OF CHAPTER1 D.C. CIRCUITS2 A.C. FUNDAMENTALS3 SINGLE PHASE AC CIRCUITS4 THREE PHASE AC CIRCUITS5 SINGLE PHASE TRANSFORMERS6 D.C.MOTORS7 FRACTIONAL HORSE POWER MOTORS8 INSTALLATIONS,EARTHING AND TROUBLE SHOOTING9 DIFFERENT TYPES OF MOTORS
WHAT IS A TRANSFORMER?• The Transformer is a device that transfers electrical energy from one electrical circuit to another electrical circuits through the medium of magnetic field and without a change in the frequency.
CORE TYPE TRANSFORMER(Example of Core Type transformer)
SHELL TYPE TRANSFORMER(Example of Shell Type transformer)
BERRY TYPE TRANSFORMER(Example of Berry Type transformer)
1. STEP UP TRANSFORMER :-This type of transformers to increasethe voltages in secondary coil. Itconsist of a primary and two or threesecondary windings. The transformerused in a valve type of radio receiversor an amplifiers. In this transformersecondary windings is increasing thanprimary winding. Secondary voltagedepends up on primary coil.
2. STEP DOWN TRANSFORMER :-This type of transformers to decreasethe voltages in secondary coil. Numberof turns will be decreased in secondarywinding so always less voltages todraw in this coil. This type oftransformers are used in radiofrequency in electronic devices.
3. CENTRE TAPPED TRANSFORMER :- This type of transformer out put todraw in centre tapping so its calledcentre tapped transformer.It is used in full wave rectificationpurposes.
4. MULTIPLE TRANSFORMER :- Multipletransformers are used for multiple out putscoming in that transformer. Input given toconstant voltage but output is differentvoltages like as battery eliminator. These alloutputs are to changed by a Rotary switchbut we are using only one out put.Ex. In this battery eliminator different outputs used like as 1.5v,3v,4.5v,6v,7.5v,9v,and 12voltages are used.
5. AUTO TRANSFORMER :- It is quitedifferent type of transformer whichconsists of only one winding. Thiswinding are common tap terminal.This type of transformer can be usedas voltage step up, as well as stepdown transformer, It works only on A.C only and also used in EHTtransformer used in T.V receivers, sortof auto transformer frequency is15625 Hz.
6. DRIVER TRANSFORMER :-All transformers input and outputvoltages are different but this only onetransformer input how much voltageyou are given same voltage is to drawin secondary winding. Restricted A.Cvoltage is to draw in this transformer.This type are used in SMPStransformers.
7. EHT TRANSFORMER :- This type oftransformer output to draw in KiloVoltages. Because this transformerscore is made up of ferrite core, thiscore is developed high voltage. Itsused in TV’s, Monitors.Another name is LOT (Line OutputTransformer), FBT ( Field backtransformers), FOT (Field OutputTransformer).
8. SWITCH MODE TRANSFORMER :- Input given to constant voltages butoutputs are different voltages at a wecan used in secondary winding. Thistype transformers are used in SMPS.Ex:- SMPS output voltage is12v,5v,0v,and 0v.
9. RELAY :-* This type of transformers are used inremote sensing projects for automatic system controlling. In this voltage up to 5v only. OR It is an electronic switch which can sense the fault and gives triping command to the circuit breaker.
10. IFT :- It is a sort of R.F transformer which is especially designed fortransform electrical energy at specified frequency. The I.F value for radio receivers is kept between 450Khz to 470Khz. Each winding is transformerhas a capacitor is connected across thewinding. IF transformer depends up on frequency tuning purpose.
11. RADIO FREQUENCYTRANSFORMER :-All transformers working above 20Khzare called R.F. transformers. TheOscillator and antenna coils of a radioreceiver are also R.F. transformers. R.Fand I.FTransformers are corelesstransformers.
12. IDEAL TRANSFORMER1.There are no losses.2.Its windings have no ohmicresistance.3.There is no magnetic leakage.4.Negligible current required for flux.5.The permeability of the core is high
LOSSES IN TRANSFORMERCOPPER LOSSES CORE / IRON LOSSES• Due to resistance of • There are two losses i.e. windings. Hysteresis Loss and Eddy• Heating is more. current Loss.• It is the product of • H.L.= Takes place in core of resistance and square of the transformer. current at both sides. • E.C.L.=are currents induced in conductors when a conductor is exposed to a changing magnetic field.
1) Core or Iron Losses are constant.2) They are reduced by silicon steel.3) All the losses are converted intoheat.4) Due to heating, There are manylosses like core, windings and otherparts.5) Cooling system is required for lifelong period to maintain transformerlife.
EMF EQUATION OF TRANSFORMER :- E = ???? For Primary winding For Secondary winding and For no load condition?
Full Load Primary CurrentFull Load Secondary Current ?????????