As we have known, the inverter is an electronic device to convert DC into AC electricity. Pure sine wave inverter used to operate the high-end electronic equipment such as medical equipment, digital music amplifiers, higher-end televisions, and a must for laser printers. There is the very low harmonic distortion in the output voltage waveform.

There are two types of inverter are True / Pure sine wave inverter and Modified sine wave inverter, both  transformer based. The sine wave transformer based can operate medium to larger units. These types of inverters are required for net metered installations. This is also used in large RV’s and boats.

12V Pure Sine Wave Inverter Schematic

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12V Pure Sine Wave Inverter

Generating pure sine wave is done through mathematical representation manipulation of the original sine wave by dividing the half-sine wave to a few number segmentation.

Pure sine wave inverter will convert the 12V from the battery into 110V AC, 50 Hz sine wave. Microcontroller IC used is the Atmel 89S2051. The 89S2051 produce pulse train alternately from port A and Port B for half the positive and negative half sine wave.

Pulse train is directed at the primary side of the transformer through the IRF44N MOSFET power switching circuit.  The output voltage 110V AC will be available on the secondary side of the transformer and then filtered through a filter LPF and generate a sine wave. For more info Download this pure sine wave inverter.