1. AC Power Transfer Wirelessly by HF

2. AC Power Transfer Wirelessly by HF
Introduction
The main objective of this project is to transfer the AC power wirelessly from a power source to electrical loads using a high-frequency resonating air core transformer to develop the frequency from 50Hz to 40KHz for transferring power over a distance of 3cm.Wireless power transfer can make a remarkable change in the field of electrical engineering , which eliminates the usage of conventional copper cables and current carrying wires. Based on this concept, the project is developed to transfer the power within a small range.

3. AC Power Transfer Wirelessly by HF
Block Diagram

4. AC Power Transfer Wirelessly by HF
Hardware Requirements
8051 series Microcontroller
Relay Driver IC
Relays
7 segment display
Opto-isolators
Crystal
LED
Resistors
Capacitors
Diodes
Transformer
Voltage Regulator

5. AC Power Transfer Wirelessly by HF
Software Requirements
Keil compiler
Languages: Embedded C or Assembly

6. AC Power Transfer Wirelessly by HF
HF Transformers
Electric power transmission over long distances.
High-voltage direct-current HVDC power transmission systems.
Large, specially constructed power transformers are used for electric arc furnaces used in steelmaking.
Rotating transformers are designed so that one winding turns while the other remains stationary.

7. AC Power Transfer Wirelessly by HF
HF Transformers

8. AC Power Transfer Wirelessly by HF
HF Transformers
A common use was the video head system as used in VHS and Beta video tape players.
These can pass power or radio signals from a stationary mounting to a rotating mechanism, or radar antenna.

9. AC Power Transfer Wirelessly by HF
AC Power Flow
Different lines have different values for R, XL , and XC , depending on:
• Length
• Conductor spacing
• Conductor cross-sectional area
XC is equally distributed along the line

10. AC Power Transfer Wirelessly by HF
Resistance in AC Circuits
Resistance (R) is the property of a material that opposes current flow causing real power or watt losses due to I2R heating
Line resistance is dependent on:
Conductor material
Conductor cross-sectional area
Conductor length
In a purely resistive circuit, current and voltage are in phase; instantaneous power equaling the product of the two

11. AC Power Transfer Wirelessly by HF
Wireless Power Transfer
wireless power involves the transmission of energy from a transmitter to a receiver via an oscillating magnetic field.
To achieve this, Direct Current (DC) supplied by a power source, is converted into high frequency Alternating Current (AC) by specially designed electronics built into the transmitter.

12. AC Power Transfer Wirelessly by HF
Wireless Power Transfer
wireless power involves the transmission of energy from a transmitter to a receiver via an oscillating magnetic field.
To achieve this, Direct Current (DC) supplied by a power source, is converted into high frequency Alternating Current (AC) by specially designed electronics built into the transmitter.

13. AC Power Transfer Wirelessly by HF
Applications of Wireless Power Transfer
Reduce costs associated with maintaining direct connectors .
Greater convenience for ​the charging of everyday electronic devices
Safe​ power transfer to applications that need to remain sterile or hermetically sealed
Electronics can be fully enclosed, reducing the risk of corrosion due to elements such as oxygen and water.

14. AC Power Transfer Wirelessly by HF
Applications of Wireless Power Transfer
​Robust and consistent power delivery to rotating, highly mobile industrial equipment​
​Delivers reliable power transfer to mission critical systems in wet, dirty and moving environments.

15. AC Power Transfer Wirelessly by HF
Rectifier
A rectifier is an electrical device composed of one or more diodes that converts alternating current (AC) to direct current (DC).
A diode is like a one-way valve that allows an electrical current to flow in only one direction. This process is called rectification. 
A rectifier can take the shape of several different physical forms such as solid-state diodes, vacuum tube diodes, mercury arc valves, silicon-controlled rectifiers and various other silicon-based semiconductor switches. 

16. AC Power Transfer Wirelessly by HF
Rectifier
Rectifiers are used in various devices, including:
DC power supplies
Radio signals or detectors
A source of power instead of generating current
As flame rectification to detect the presence of flame
High-voltage direct current power transmission systems

17. AC Power Transfer Wirelessly by HF
Rectifier

18. AC Power Transfer Wirelessly by HF
Voltage Regulator
A voltage regulator generates a fixed output voltage of a preset magnitude that remains constant regardless of changes to its input voltage or load conditions.
There are two types of voltage regulators: linear and switching.
A linear regulator employs an active (BJT or MOSFET) pass device (series or shunt) controlled by a high gain differential amplifier.

19. AC Power Transfer Wirelessly by HF
Voltage Regulator
It compares the output voltage with a precise reference voltage and adjusts the pass device to maintain a constant output voltage.

20. AC Power Transfer Wirelessly by HF
Capacitors
When apply a voltage to a capacitor, a electrical field is created between the capacitor’s plates.
Energy provided by a voltage difference is stored in the electric field. The higher the voltage or bigger capacitor (higher capacitance), the stronger the electric field and more energy is stored inside the capacitor.
Capacitor does however have a limit as to the amount of energy it can store.
Energy stored in capacitor’s magnetic field can be retrieved.

21. AC Power Transfer Wirelessly by HF
Capacitors
It is clear that a capacitor stores energy in the form of a electric field created by potential difference across the capacitor plates.

22. AC Power Transfer Wirelessly by HF
The Coil
An electromagnetic coil (or simply a "coil") is formed when a conductor (usually an insulated solid copper wire) is wound around a core or form to create an inductor or electromagnet.
Primarily used for transferring energy from one electrical circuit to another by magnetic coupling
Common types of Electromagnetic coils: Tesla coil, Barker Coil, Choke coil, Maxwell coil etc.
In our set-up : Primary coil- two 9 turns in parallel – 9 cm diameter, Secondary coil- 36 turns, 9 cm diameter

23. AC Power Transfer Wirelessly by HF
Working Principle
This project can be used for charging batteries that physically are not possible to be connected electrically such as pace implanted in human body that runs on a battery.
The patient is required to be operated every year to replace the battery.
This project is designed to charge a rechargeable battery wirelessly for the purpose.
Since charging of the battery is not possible to be demonstrated, we are providing a DC fan that runs through wireless power.

24. AC Power Transfer Wirelessly by HF
Working Principle
This project is built upon using an electronic circuit that converts AC 230V 50Hz to AC 12V, High frequency.
The output is fed to a tuned coil forming as primary of an air-core transformer. The secondary coil develops a voltage of HF 12volt.
Thus, the transfer of power is done from the primary (transmitter) to the secondary, which is separated with a considerable distance (say 3cm).

25. AC Power Transfer Wirelessly by HF
Working Principle
Therefore, the transfer could be seen as the primary transmission and the secondary receives the power to run the load.
Moreover, this technique can be used in number of applications: to charge a mobile phone, iPod, laptop battery, and propeller clock wirelessly.
And also this kind of charging provides a far lower risk of electrical shock as it would be galvanically isolated.

26. AC Power Transfer Wirelessly by HF
Advantages
Lower Frequency Operation – The operating frequency range is in the kilohertz range.
Low Cost - The entire system is designed with discrete components that are readily available & of affordable price.
Practical for Short Distance – The designed system is very practical for short distance as long as the coupling coefficient is optimized.

27. AC Power Transfer Wirelessly by HF
Dis Advantages
High Power Loss – Due its air core design the flux leakage is very high. This results in a high power loss and low efficiency.
Non-directionality – The current design creates uniform flux density and isn't very directional
Inefficient for longer distances- The efficiency drops exponentially with increase in distance.

28. AC Power Transfer Wirelessly by HF
Conclusion
In this PPT we have seen AC Power Transfer Wirelessly by HF, and it’s working principle, advantage and disadvantage along with applications