A Tesla coil is an electrical transformer device invented by Nikola Tesla in 1891. It is used to produce high-voltage, low-current, high-frequency alternating-current electricity. Tesla coils can be used as transmitters and receivers of radio signals and as sources of extremely high voltages. They are also used in medical devices such as x-ray machines and cancer treatment equipment.
Tesla coils typically consist of two parts: a primary coil and secondary coil, each with its own capacitor. The primary coil is connected to a power source, while the secondary coil is connected to the load (the thing that the electricity will power). When the power source is turned on, it charges the capacitor in the primary coil. This creates a magnetic field around the primary coil. When the capacitor in the secondary coil reaches its maximum charge, it discharges into the load, producing an electric current. The discharge causes sparks to jump between metal plates called spark gaps, which are located at either end of the secondary coil. These sparks create noise and light, but they also generate heat energy that can damage sensitive electronic components if they are not properly protected.
Tesla coils can generate voltages that exceed one million volts (1 MV). The largest ever built had a voltage of 50 MV and could produce sparks over 30 meters long! The frequency of the alternating current generated by a Tesla coil depends on its design, but it is usually between 100 kHz and 10 MHz. The higher frequencies allow for more efficient transfer of energy from the primary to secondary coils.