WPT

1. Wireless Charging Circuit
Using Inductive Coupling
BY:-
Siddhant Singh

2. Overview
What is wireless power
transmission(WPT)?
Why is WPT?
History of WPT
Types of WPT
◦
Techniques to transfer energy wirelessly
Advantages and disadvantages
Applications
Conclusion11/2/14 Wireless Power
Transmission
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3. What is WPT?
The transmission of energy from one
place to another without using wires
Conventional energy transfer is using
wires
But, the wireless transmission is
made possible by using various
technologies
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Transmission
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4. Why WPT?
Reliable
Efficient
Fast
Low maintenance cost
Can be used for short-range
or long-range.
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Transmission
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5. History
Nikola Tesla in late 1890s
Pioneer of induction techniques
His vision for “World Wireless System”
The 187 feet tall tower to broadcast
energy
He managed to light 200 lamps from a
distance of 40km
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6. Energy Coupling
The transfer of energy
◦
Magnetic coupling
◦
Inductive coupling
Simplest Wireless Energy coupling is
a transformer
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7. Inductive coupling
Primary and secondary coils are not
connected with wires.
Energy transfer is due to Mutual
Induction
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8. An example
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9. Block Diagram of circuit
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10. Description of diagram
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Works on the principle of inductive
coupling
Contains two sections-The
Transmitter section and the Receiver
section
Transmitter coil converts the DC
power to high frequency AC signal
Receiver coil receives the power and
convert it into AC signal

11. Transmitter Section
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12. Transmitter Section
Description
 DC power Source: It consists of a step
down transformer that step downs the
supply voltage to a desired level, and
a rectifer circuit convert that AC voltage to
DC signal
Oscillator Circuit: A modified Royer
Oscillator circuit is used in our project. With
this circuit we can easily achieve a high
oscillating current for the transmitter coil.
Two N channel enhancement power
MOSFET are used11/2/14 Wireless Power
Transmission
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13. Transmitter Section (cont…)
the transmitter coil L(inductor)
 resistors R1,R2,R3 and R4 (works as
a biasing network for Q1&Q2)
 The operating frequency of the
oscillator is determined by the
resonance formula given below
F = ½ × π × √ (LC)
The equation for finding the
inductance of a single layer air core11/2/14 Wireless Power
Transmission
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14. Recevier Section
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15. Reciver Section Description
consists of receiver coil
 rectifier circuit and a voltage
regulator IC.
The rectifier circuit in the receiver
section converts this AC voltage in to
DC
Voltage control IC helps to provide a
constant limited regulated output
voltage to the load for charging
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16. Recevier section (cont….)
 LM 7805 voltage regulator IC is used
 The IC gives a regulated 5V as its
output
It don’t allow more than 5V to the
output.
Copper wire having diameter of 8cm
is used.
equation for finding the inductance of
a single layer air core coil is given11/2/14 Wireless Power
Transmission
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17. Advantages of near-field
techniques
No wires
No e-waste
Need for battery
is eliminated
Efficient energy
transfer using RIC
Harmless, if field
strengths under
safety levels11/2/14 Wireless Power
Transmission
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18. Disadvantages
Distance constraint
Field strengths have to be under
safety levels
Initial cost is high
In RIC, tuning is difficult
High frequency signals must be the
supply
Air ionization technique is not feasible
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Transmission
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19. Applications
Near-field energy transfer
◦
Electric automobile charging
 Static and moving
◦
Consumer electronics
◦
Industrial purposes
 Harsh environment
Far-field energy transfer
◦
Solar Power Satellites
◦
Energy to remote areas
◦
Can broadcast energy globally (in future)11/2/14 Wireless Power
Transmission
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20. Conclusion
Transmission without wires- a reality
Efficient
Low maintenance cost. But, high initial cost
Better than conventional wired transfer
Energy crisis can be decreased
Low loss
In near future, world will be completely
wireless
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21. References
S. Sheik Mohammed, K. Ramasamy,
T. Shanmuganantham,” Wireless
power transmission – a next
generation power transmission
system”, International Journal of
Computer Applications (0975 – 8887)
(Volume 1 – No. 13)
Peter Vaessen,” Wireless Power
Transmission”, Leonardo Energy,
September 200911/2/14 Wireless Power
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22. THANK YOU!
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