Wireless Power Transmission

Wireless power Transmission

There are a number of ways to transmit power wirelessly. Few of them are-

->Inductive coupling- This type usually has a Short range and they use Wire coils as antennas . This type of wireless power transmission is used in Electric tooth brushs and razor battery charging, induction stovetops and industrial heaters.

->Resonant inductive coupling- the range is mediocre and they use Tuned wire coils or lumped element resonators as antennas. Few applications are Charging portable devices (Qi), biomedical implants, electric vehicles, powering busses, trains, MAGLEV, RFID, smartcards etc.

->Capacitive coupling- the range is pretty Short and use Electrodes antennas. Common appplications are Charging portable devices, power routing in large scale integrated circuits, Smartcards.

->Magneto dynamic coupling- the range here too is Short and Rotating magnets are used as antennas. They are used in Charging electric vehicles etc.

->Microwaves- this type has a Long range and Parabolic dishes, phased arrays or rectennas are used as antennas. Applications include Solar power satellite, powering drone aircraft.

->Light waves- Long range can be achieved and Lasers, photocells, lenses are used to transmit power. this method may be used for Powering drone aircraft, powering space elevator climbers

We Are using INDUCTIVE COUPLING type for our project

principle of induction

**If your used to working with electronics, you can just braze the article. This is designed for beginners.

1. 25 Guage Magnetic Wire

2. 2N2222A or BD135 or TIP35c transistor ( I used BD135, using this will give the best results)

3. LED's (of different colours)

4. Tape

5. 9 V Battery & holder

6. Soda bottle

soldering iron, soldering lead, sand paper, scissors

• Cut the soda bottle as shown in the picture.
• Now wind the magnetic wire around the cut bottle.
• Make 3 turns.
• On the 4th turn, make a notch(loop) as shown in the figure.
• Make another 3 turns.
• Now you must have a total of 7 turns. (3 initial turns + 1 turn which has the loop + 3 Final turns)
• Slide the coil off the bottle.
• Once your done you must have 3 terminals(ends) in total as shown in the photo. (1 Beginning terminal+1 notch(loop) terminal + 1 final terminal)
• Tape 3 parts of the coil to keep it from coming apart.

• Wind the magnetic wire around the same cut bottle about 15 turns so that you will get two ends as shown in the picture.
• Tape 4 parts of the coil to keep it from coming apart.

Any transistor will have 3 terminals, they are-

1) Emitter

2) Base

3) Collector

Identification of Terminals-

-> Usually the middle terminal is the Base.

-> Incase of 2N2222A - The transistor has a semi-circular shape. Hold the transistor so that that flat side is facing you. Now the left terminal is the Emitter, the middle terminal is the Base and the right terminal is the Collector.

For further clarification , refer to the attached photos of all three transistors which can be used.

***Make sure that you remove the invisible varnish coat on the magnetic coil while soldering. You can do this by using the sand paper and rubbing the tips of the wire till the coating is gone.

Soldering the transmission coil-

• The emitter of the 2N2222A (or the other transistors) transistor is soldered to the black wire of the 9V battery holder.
• The two ends of the transmission coil are soldered to base and collector of the transistor (it doesn't matter which way they are soldered).
• The red wire of the battery holder is soldered to the notch of the transmission coil as shown in the circuit diagram.

Soldering the Receiver coil-

The two ends of the LED is soldered to the two ends of the receiver coil. You can solder the ends in anyway, it wont make a difference.

***Make sure that you remove the invisible varnish coat on the magnetic coil while soldering. You can do this by using the sand paper and rubbing the tips of the wire till the coating is gone.

Finally its time for us to power this rig up !

Attach the 9V battery to the battery holder.

ONLY USE 9V BATTERY for this project because if we use a battery of higher voltage, there is a chance of the transistor getting damaged.

Your Wireless power transmission coils are ready !

If you are curious and would like to further investigate this phenomenon, you can make receiver coils with any numbers of turns or a larger/smaller diameter . Try out various combinations and see what happens. I Promise you, you will see a difference.

Thank You :)