SAKARYA UNIVERSITY JOURNAL OF SCIENCE, vol.25, no.4, pp.914-925, 2021 (Peer-Reviewed Journal)
The increasing integration of photovoltaic (PV) plants into conventional power systems has led
to the need to examine the effects of these plants on the system dynamics. By considering this
increasing integration rate, in this study, a well-known IEEE-9 bus power system is modified
by adding a PV plant in DigSilent Powerfactory environment. Three different transient cases
are tested by using PV plant control units designed by Western Electricity Coordinating Council
(WECC). The effect of the load and line transient disconnections and 3-phase short circuit fault
on modified power system are investigated as case-I, case-II, and case-III, respectively. In all
cases, two sub-cases are considered according to the location as a distance factor. As a result,
comparison of PV different control options (DCO) is done in terms of voltage stability for these
3 cases and the obtained results are discussed in detail.