Today I,m gonna demonstrate the wireless power transfer technology using minimum components and making it as simple as it can be.

There is no high voltage is involved in this project so it,s pretty safe to make . As you may know wireless power transfer is actually an air core transformer(Step Down). So all we need to do is making and air core transformer and changing the polarity of current flowing through. So lets do it...

Step 1: Theory

The idea behind the wireless power transfer is something similar to the Air core transformer. we all know that a varying electric field in primary winding of transformer causes current induced in secondary winding.

In normal transformers they have iron core to increase the magnetic field induced, thus providing better efficiency. but We can also make Air core transformers by keeping both the winding closer. and current will be induced in secondary winding. because electromagnetic waves can travel through air/space, just like Radio waves do. they are nothing but the vary high frequency electromagnetic waves.

Now we are gonna make a Air core transformer. you can achieve larger distance between primary and secondary winding with the higher voltage input at primary winding switching at higher frequency.

Step 2: Components Needed

Now, as i have told you that this project is demonstrating the wireless power transfer with minimum components required. you only gonna need things laying around you if you are an engineer or hobbyist.

1. Enameled Copper wire 24SWG or similar in AWG

2. A LED

3. Arduino or any other Micro-controller

4. Soldering kit

Step 3: Making Winding/coils

To make coils take a round cylindrical object 3-4 cm diameter(larger diameters will work also but may have some other effects as our voltage is too low).For primary winding, wrap the wire around the object and make at least 50-60 turns of it.tie the coil with the two ends of the wire to hold the coils turns at there place or it will uncoil itself. tin the ends with your solder iron.

do the same for secondary winding and make 40-50 turns of it. we have our coils now.

Step 4: Connecting Things

Connect the led to the secondary winding. no need to add anything extra as LED is a diode itself. so it can handle the polarity reverse of current.

connect your primary winding to the any two digital pins of the arduino or your any other micro. mine was connected to D12 and D11.

Step 5: Programming Arduino

There is nothing much to do in the coding area. we all need to reverse the current polarity at primary winding pins.

//Author: Abhi verma

//created at: 10/1/2017

//This code is in public domain. IF YOU ARE WORKING WITH HIGH VOLTAGE THEN USE PRECAUTIONS AND BE CAREFUL. Author is not liable for any damage.

//Wireless Power Transfer Prototype

void setup() {

// Initializing pins as output

pinMode(11,OUTPUT);

pinMode(12,OUTPUT);

}

void loop() {

//changing pin states to reverse the polarity of coil. doing it as fast as approx. 500 Khz.

digitalWrite(11,LOW);

digitalWrite(12,HIGH);

delayMicroseconds(1);

digitalWrite(12,LOW);
digitalWrite(11,HIGH);

delayMicroseconds(1);

}

Step 6: Testing

Power up your arduino and put the both coils closer. you can see your led is turning ON. it become brighter as you brings both coils more closer.

with the same approach you can make wireless power supply by making stronger coils and applying higher voltage at primary winding.