Simply,harmonic currents do affect voltage as their caused voltage drops are of the same harmonic order. There are plenty articles and now, even text books deals with harmonics and power quality topics.

Harmonics are harmful in any circuit, especially Odd number harmonics i.e 5th, 7 th, 9 th harmonics are most harmful to the circuit. We can view Harmonic wave forms using Power analyzers. Practical I found harmonics at my company which produced by a old V.F.D. (Variable Frequency Drives) using with out filter. By using Meco PHA 5850 Power and Harmonics Analyzer we studied and designed a Three filter and reduced harmonics to below to minimum level as well power consumption too.

Harmonic currents produce harmonic voltage of the same frequency. You can observe this with a modern oscilocope or a power analyzer.

Thank you for your response.I have some questions regarding Voltage fluctuations in the Grid,Flicker.Do you have experience with that?Can you also please name few good books that I can refer to know more about how current inter-harmonics is affecting the grid?(technical ofcourse)

If you take power scope you can observe the waveform.or else u can observe it in matlab simulation programme.

Digital Signal processing in Power Quality. It talks about Flicker problem in the grid.What I meant to say was Frequencies that are side lobes around the fundamental current frequency will lead to modulating frequency that causes flicker when slow enough.This modulating frequency is the other frequency.

When the current with a mix of frequencies between 0.5Hz to 85Hz and the fundamental 50Hz passes through defined impedance (and impedance angle),will I be able to measure a proportional voltage change over the impedance?Will this be a linear process (with inter-harmonics?)How will the power factor vary?

Also can you please shed some light on Rectangular Voltage changes.

Thank you.

When the waveform becomes non sinuslike, it can be represented by the sum of the frequencies in its spectrum. The components of a periodic square or pulse waveform is then represented by the sum of its fourier transform components. Intermodulation distortion by nonlinear components in the network can then create new frequencies by mixing different frequencies just as in audio and RF circuits. A linear network on the other hand does not create new frequencis, just phase shifts. Another problem in grid networks is that the network can act as a transmission line if the transmission line lengths are long enough and/or frequencies high enough. The problem of simulation of large systems is as I understand it non trivial. ASEA in Sweden used to (1980:s?) have a huge analog hybrid computer located in the Ludvika plant in order to simulate the entire Swedish and part of the north European grid. I remember that the behavior in large simulations frequenly was chaotic, as in chaos theory.