A brief description of couple inductor, dot convention, energy analysis along with examples.

2. GROUP MEMBERS
EE171007
EE171008
EE171011
EE171022
EE171049
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3. BASIC LAWS OF ELECTROMAGNETIC
INDUCTION
• FARADAY’S LAW:
TIME VARYING FLUX IN THE CONDUCTOR INDUCES VOLTAGE IN IT.
• AMPERE’S LAW:
THE CURRENT FLOWING THROUGH A CONDUCTOR GENERATES A MAGNETIC FIELD AROUND THE
CONDUCTOR.
• LENZ’S LAW:
THE CURRENT INDUCED BY A MAGNETIC FIELD GENERATES ANOTHER MAGNETIC FIELD OPPOSING THE
FIRST FIELD.
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4. COUPLE INDUCTOR
• As current flows through a conductor, a magnetic field is generated.
Steady-state current will induce a steady magnetic field
• Likewise a time-varying current will induce a time varying magnetic
field.
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6. • Inductors can be coupled in two ways:
• In series
• In parallel
Mutually Connected Inductors in Series
• When inductors are connected together in series so that the magnetic
field of one links with the other, the effect of mutual inductance either
increases or decreases the total inductance depending upon the
amount of magnetic coupling.
• There are further two types of coupling in series
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7. CLASSIFICATION
CUMULATIVELY COUPLED
If the magnetic flux produced by the current flows through the coils in
the same direction then the coils are cumulatively coupled.
DIFFERENTIALLY COUPLED
If the current flows through the coils in opposite directions then the
coils are differentially coupled.
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8. INDUCTORS IN PARALLEL
•Inductors are said to be connected together in Parallel when both of
their terminals are respectively connected to each terminal of
another inductor or inductors.
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9. MUTUALLY COUPLED INDUCTORS IN
PARALLEL
• The effect of this mutual inductance depends upon the distance apart
of the coils and their orientation to each other.
Cumulatively coupled Differentially coupled
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10. TYPES OF INDUCTANCES
• Mutual inductance
• Self-inductance
Mutually Inductance
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11. THE DOT CONVENTION
• Required to determine polarity of “mutual” induced voltage.
• A dot is placed in the circuit at one end of each of the two
magnetically coupled coils to indicate the direction
of the magnetic flux if current enters that dotted
terminal of the coil.
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12. Correct sign depends on two things
1. Spatial orientation of two winding
• Additive
• Subtractive
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13. •ADDITIVE
•SUBTRACTIVE
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14. The reference marks given to the currents and voltage
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16. HENCE WE DRIVE
• Mutual inductance is additive when both current reference
directions point toward or both point away from dotted
terminals; otherwise, it is subtractive.
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17. EXAMPLE 01
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18. EXAMPLE 02
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19. ENERGY ANALYSIS
To determine total energy in magnetic coupled coils.
Multiply equation 1 by i1(t) & 2 by i2(t)
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20. • The p1(t) & p2(t) are power absorbed with
inductor 1 & 2
• The total power is the sum of individual
inductor power
PT(t)=P1(t) + P2(t)
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21. • Each of bracket term is a perfect derivative
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22. • Total energy stored in
• Therefore, the total power is
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