  Increasing photovoltaic (PV) penetration in the distribution system can often
lead to voltage violations. Mitigation of these violations requires reactive
power intervention from PV inverters. However, the unbalanced nature of the
distribution system leads to mixed effects on the voltages of nearby nodes for
each inverter injecting or absorbing reactive power. In particular, reactive
power absorption to reduce over-voltage in one phase can exacerbate
over-voltage in a different phase. In this paper, the factors impacting the
incremental and decremental voltage effects of reactive power intervention are
analyzed in detail. The result of these effects on the distribution system
performance is presented to highlight their significance and the need to factor
them in for any coordinated voltage control algorithm.
