Tesla coil

TESLA COIL 

Now a days there are many wireless technology like Bluetooth, Wi-Fi, G.P.S, wireless communication phones, but doesn't have a wireless electricity.

     The great scientist Nicola Tesla dreamed of creating a way to supply power to the world without stringing wires across the globe. And it is almost done though his invention in 1891, which is known as Tesla Coil. 

     A Tesla coil is an electrical resonant transformer circuit designed by inventor Nicola Tesla in 1891. It is used to produce high-voltage, low-current, high-frequency alternating current electricity. The first system that could wirelessly transmit electricity, the Tesla coil was a truly revolutionary invention. 

Fig. Circuit Diagram 

The main component in this circuit is the secondary coil, which is made up winding a magnetic wire(enamelled) around a cylindrical object ( any non-conductive object will work). A Tesla coil consist of two parts a primary coil and secondary coil, each with it's capacitor (capacitors store electrical energy just like batteries). The two coil and capacitor are connected by a spark gap- a gap of air between two electrodes that generates the spark of electricity. An outside source hooked up to a transformer power the whole system. Essentially the Tesla coil is two open electric circuit connected to a spark gap. 

A high voltage supply transformer (T), to step the AC main voltage up to a high enough voltage to jump the spark gap. Typical voltages are between 5 and 30 kilovolts(KV). A capacitor (C1) that forms a tuned circuit with the primary winding L1 of the Tesla transformer. A spark gap (SG) that acts as a switch in the primary circuit. The Tesla coil (L1, L2), an air-core double tuned resonant transformer, which generates the high output voltage. Optionally, a capacitive electrode(top load)(E)  in the form of a smooth metal sphere or torus attached to the secondary terminal of the coil. It's large surface area suppresses premature air breakdown and are discharge, increasing the Q-factor and output voltage. 

          

   A tesla coil needs a  high voltage power source. A regular power source fed through a transformer can produce a current with tge necessary power (at least thousands of volts). In this case, a transformer can convert the low voltage of main power into the high voltage 

How it work

     The power source is hooked up to the primary coil. The primary coil capacitor acts like a sponge and soaks up the charge. The primary coil itself must be able to withstand tge massive charge and huge surges of current, so the coil is usually made out of copper, a good conductor of electricity. Eventually, the capacitor builds up so much charge that it breaks down the air resistance in the spark gap. Then similar to squeezing out a soaked sponge, the current flows out of the capacitor down the primary coil and creates a magnetic field. 

    The massive amount of energy makes the magnetic field collapse quickly, and generate an electric current in the secondary coil. The voltage zopping through the air between the two coils creates sparks in the spark gap. The energy sloshes back and forth between the two coils several hundred times per second, and builds up in the secondary coil and capacitor. Eventually, the charge in the secondary capacitor gets so high that it breaks free in a spectacular brust of electric current.  

    The resulting high frequency voltage can illuminate fluorescent bulb several feet away with no eletrical wire connection. In a perfectly designed Tesla coil, when the secondary coil reaches its maximum charge the whole process should start over again and the device should become self sustaining. In practice however, this does not happen. The heated air in the spark gap pulls some of the secondary coil and back into the gap, so eventually the tesla coil will run out of energy. This is why the coil must be hooked up to an outside power supply. 

Fig. Schematic diagram of Tesla coil 

Principal of Tesla coil 

       The principal behind the Tesla coil is to achieve a phenomenon called resonance. This happens when the primary coil shoots the current into the secondary coil at just the right time to maximize the energy transferred into the secondary coil. Think of it as timing when to push someone on a swing in order to make it go as high as possible. Setting up a Tesla coil with an adjustable rotary spark gap give the operator more control over the voltage of the current it produces. This is how coils can create crazy lightning displays and can even the set up to play music timed to bursts of current. 

Applications of Tesla coil 

    

         At present these coils do not requires large complex circuit to produce high-voltage nevertheless, small Tesla coil find their applications in a range of sector 

• Aluminum welding .
• Cars use these coils for the spark plug ignition. 
• Created Tesla coil fans, used to generate artificial lighting, sound like music Tesla coils in Entertainment and education industry are used as attraction at electronics fairs and Science museums.
• High vacuum system and arc lighters
• Tesla coil circuit were used commercially in sparkgap radio transmitters for wireless telegraphy until the 1920.