# Effects of Powerline Harmonics?

1. May 13, 2015

### Eranda

What kind of effects that provides to the power lines due to the harmonics? Please consider those harmonics are generated through electronic equipments?

2. May 13, 2015

### Staff: Mentor

Welcome to the PF.

Please tell us what you know so far. How does electronic equipment generate harmonics on the AC Mains powerline? Are you familiar with the concept of "Power Factor"?

Last edited: May 16, 2015
3. May 16, 2015

### Staff: Mentor

@Eranda -- please send me a message when you are able to answer my questions above, and I will re-open this thread.

4. May 17, 2015

### Eranda

Yp. I'm familiar with the power factor. I found that harmonics are generated through electronic devices; mostly due to SMPS. That switching purpose generates harmonics since the supply is not continuously provided.
As you meant the power factor, some of the power factor correction capacitor banks cause to this harmonics. As far as I know the Impedance of the p.f correction capacitor is inversely proportional to the frequency & Impedance of the source is directly proportional to the frequency. If the p.f correction capacitor is not specifically designed for these conditions, harmonics generates.
Am I missing something here?

5. May 17, 2015

### Staff: Mentor

Well, you are talking about three different things. When you talk about SMPS noise, it is not at harmonics of the powerline frequency (50/60Hz). SMPS noise coupled back into the AC Mains powerline is at the switching frequency of the power supply and harmonics of that switching frequency.

And power factor has a couple different contexts. When you have a very inductive load, like with AC motors, then yes, adding some capacitance can help to get the PF closer to the ideal number of 1.0. But again, that does not appear to be what your question is asking. Can you tell us how the PF is defined? What kind of load has a PF of 1.0? How can powerline harmonics (of 50/60Hz) be generated by a load? What kind of load generates those harmonics, and why?