Hi,
As part of a project on inverters for college i have simulated the harmonics of the line voltage.

The theory states that there should be no 3X harmonics as they are in time phase of each other. In other words they cancel each other out.
When i use the FFT function i get around 500mv for the 3rd, 9th, 15th. . .
harmonics.

Why is this?

Thanks.

 

When i use the FFT function....

What are you using it on?

 

It's an orcad Pspice A/D simulation.

 

Is this 'line voltage' the incoming mains?

 

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