Can someone brief me about the effect of source (Grid) X/R ratio in power system harmonic analysis?
Also the effect of voltage regulation in the main grid on the harmonic voltage distortion?
In ANSI regions, one reference may be IEEE Std 519-1992 ...Practices and Requirements for Harmonic Control in Electrical Power Systems §5. System Response Characteristics.
Source inductance (the X in the X/R ratio) will interact with capacitance and result in resonance at different frequencies. At points of resonance, the impedance is at a very high (series resonance) or very low value (parallel resonance), which affects the flow of harmonic current. The resistance R will provide damping and reduce the severity of harmonic resonance points. Voltage regulators also have an inductance that affects resonance points. There is no simple relationship of X/R ratio or voltage regulation to harmonics.