Structure and Technical Terms
A transformer consist of 3 parts, namely
Working Principle of A Transformer
Types of Current in A Transformer
The current in the primary circuit must be alternating current because alternating current can produce changing magnetic flux. A changing magnetic flux is needed to induce e.m.f. in secondary coil.
The induced current in secondary is also an alternating current. The frequency of the alternating current in secondary coil is same as the frequency of the primary current.
Types of Transformer
The number of windings in the secondary winding is greater than the number of windings in the primary coil.
The number of windings in the primary winding is greater than the number of windings in the secondary coil.
The heating effect of current in a coil
Power is lost as heat (I2R) whereby I is the current flowing through the coil and R is the resistance of the coil
Magnetization of the iron core
The energy used in the magnetization and de-magnetization of the iron core each time current changes its direction is known as hysterisis. This energy is lost as heat which subsequently heats up the iron core.
Heating effect of induced eddy currents
In the iron core. When the magnetic field in the iron core fluctuates, eddy currents are generated in the iron core.
Card 11: Factors affecting the efficiency of a transformer - Flux leakage.
Some of the induced magnetic flux from the primary coil is not transmitted to the secondary coil, therefore the e.m.f in the secondary coil is decreased.
Methods to increase the efficiency
Table of Content
8.1 Magnetism (Revision)
8.3 Application of Electromagnet
8.4 Force on a Current-carrying conductor in magnetic Feild
8.5 Elctromagnetic Induction
8.6 Application of Electromagnetic induction
8.7 Alternating Current
8.9 Sources of Energy and Generation of Electricity
8.10 Transmission of Electricity
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