Pure Sine Wave inverter

Problem statement

• In this project we are attempting to build a pure sine wave inverter by using a basic MOSFET switching circuit

• The switching circuit is operated using PWM technique, the pulse train is obtained using microcontroller AT89S2051

• A pure sine wave is obtained at the output of the transformer connected to the switching circuit

Contents

• Introduction• Mathematical modeling• Block diagram• Switching circuit• About AT89S2051• Pulse width modulation• Conclusion • Applications

Introduction

• Inverters- 2 types -Pure sine wave -Modified sine wave• A pure sine wave inverter produces a nearly

perfect sine wave output (<3% total harmonic distortion) that is essentially the same as utility-supplied grid power

Mathematical modeling

Block diagram

Switching circuit

AT89S2051

Pulse width modulation

Conclusion

• This technique in designing a pure sine wave inverter can also be adapted to obtain AC outputs for high power supplies

• By effectively modeling the pulse train with suitable frequency, it is possible to reduce the THD of the output to a minimum value and reducing the harmonic content

Applications

• Thus it is compatible with all AC electronic devices

• This is the type used in grid-tie inverters• Uninterruptible power supplies• HVDC power transmission• Induction heating• Electric vehicle drives

References

• Mathematical Manipulation of Pure Sine Wave Inverter-Didik Rostyono & Harsono Hadi

• DC/AC Pure Sine Wave Inverter-Jim Doucet,Dan Eggleston& Jeremy Shaw

• 8-bit Microcontroller with 2K/4K Bytes Flash(AT89S2051 AT89S4051)-preliminary by ATMEL corporation

• http://www.atmel.com/products/mcu8051/default.asp?source=cms&category_id=163&family_id=604&source=global_nav

• http://www.8052.com/users/AT89S52InSystemProg/• http://en.wikipedia.org/wiki/Inverter_(electrical)