1.3 Poly-voltage Load Flow (PVL)
Poly-voltage Load Flow (PVL) is a collection of distribution systems analysis, data
management, and report generating programs available under a single user interface. PVL is
Con Edison’s principle distribution system design and analysis tool and it helps Con Edison
remain a leader in reliable electric power. It is a balanced three-phase load flow analysis
program with the additional features such as demand estimation, feeder ratings, short circuit
calculations, and feeder maintenance. PVL is capable of identifying overload of transformers,
primary feeder sections, and secondary mains, low voltage of primary and secondary buses,
and provides detailed reports showing the loading and voltages of each and every component in
the system [13].
Most, if not all, Con Edison’s network distribution systems have a “N-2” (also known as
second contingency) design criteria. Customers’ peak electric demand would be met without
stressing network components beyond design limits when any two network feeders are out of
service. Based on PVL, load flow analyses are performed during design stage to make sure no
loads are dropped or reduced, and no equipment in the system is overloaded in each of the
following cases:
