Operating Principle of an Inverter
An inverter can be taken as a crude form of UPS. Obviously the main use of an inverter is only for powering common electrical appliances like lights and fans during a power failure.
As the name suggests the basic function of an inverter is to invert an input direct voltage (12VDC) into a much larger magnitude of alternating voltage (generally 110VAC or 220VAC).
Before learning how to build an inverter, let’s first understand the following fundamental elements of an inverter and its operating principle:
Oscillator: An oscillator converts the input DC (Direct Current) from a lead acid battery into an oscillating current or a square wave which is fed to the secondary winding of a power transformer. In the present circuit, IC 4049 has been used for the oscillator section.
Transformer: Here the applied oscillating voltage is stepped up as per the ratio of the windings of the transformer and an AC much higher than the input DC source becomes available at the primary winding or the output of the inverter.
Charger: During power backups when the battery gets discharged to a considerable level, the charger section is used to charge the battery once the AC mains is restored.
*Disclaimer: This project should be taken on at your own risk and is recommended for those who have experience building their own circuits. Neither the author of the article, nor Bright Hub Engineering bears no responsibility for negative outcomes to this tutorial.