Experiences in the investigation of harmonic penetrations: case studies

This paper discusses experiences in the analysis of harmonic penetrations. The discussion includes the following considerations: (1) a small linear load bus without a harmonic source is more likely to render the voltage distortion therein the most severe; (2) the variation of linear loads at the harmonic source bus will lead to a change in harmonic voltages around the system; (3) multiple harmonic sources may decrease the impact of voltage distortions; (4) there exists an optimal compensation to reduce harmonics for one special load pattern and network configuration; improper compensation will result in severe voltage distortions; and (5) an improper estimation of shunt admittance at the swing bus will render an insignificant harmonic power flow solution. Linear algebra is used to provide a mathematical background for interpreting the above phenomena. Two power systems are used to serve as samples to illustrate the numerical results.