  Long, lightly loaded feeders serving residential loads may begin to
experience voltage excursions as plug-in electric vehicle (PEV) penetration
increases. Residential PEV charging tends to occur during peak-load hours on
residential feeders, leading to increased peak loads and potential voltage
excursions. To avoid voltage excursions, two PEV charging control strategies
were investigated using the IEEE 34-bus feeder. The first strategy shifts PEV
charging energy from peak hours to off-peak hours; the other strategy allows
PEVs to provide reactive power support. Undervoltage excursions seen in a
simulation of uncontrolled charging of 200 PEVs were improved dramatically when
these two control strategies were used. The minimum voltage on the feeder
improved from 0.855 pu when PEV charging was uncontrolled to 0.959 pu when both
control strategies were applied together.
