6th Sem Electrical Engineering Department

Batch – B1 (2014 Batch)

Abhishek Choksi(140120109005)

Power Electronics 2 (2160902)

ALA PresentationOn

“Third Harmonic PWM”

Prepared By: Guided By:

Prof. Jaydeep Vanapariya

Gandhinagar Institute Of Technology

Pulse width Modulation• Pulse Width Modulation, or PWM, is a technique for

getting analog results with digital means.

• Digital control is used to create a square wave, a signal switched between on and off.

Third Harmonic PWM• In this method, the reference signal is not a pure sinusoidal wave, but

the sum of the fundamental and the third harmonic. It is shown with curve f(wt) in the following figure.

Third Harmonic PWM• Same as the SPWM method, this signal will be compared with the

triangle signal to generate PWM signals.

Third Harmonic PWM• This concept is derived from the nature of three-phase motors that

the third harmonic will be filtered out in the windings. And thus only the fundamental part will remain.

References• Hirak Patangia, Sri Nikhil Gupta Gourisetti, “Real Time Harmonic

Elimination Using a Modified Carrier”, CONIELECOMP, Mexico, Feb 2012.• Hirak Patangia, Sri Nikhil Gupta Gourisetti, “A Novel Strategy for

Selective Harmonic Elimination Based on a Sine-Sine PWM Model”, MWSCAS, U.S.A, Aug 2012.• Wikipedia --

https://en.wikipedia.org/wiki/Pulse-width_modulation#Principle