Is it possible in practice to choose 10% (5th and 7th) harmonics injected to the grid for harmonic mitigation of grid current for a grid-tied PV system?
Please refer the IEEE 519-2014:chapter 5 standard for more details on your question.It has given maximum possible individual harmonic and total harmonic distortion limits as % values. You can't say 10% or what ever the number, according to the standard you need to maintain harmonic levels below the given numbers in the standard.
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