Simulator 16 User Guide - PowerWorld

Load Modeling
Each load can be modeled as having voltage variation. The voltage variation is modeled using the Base
Load Model fields on the Load Information dialog. Thus the actual real and reactive value of each load
is determined using the following equation:
where
MW = Load MW Multiplier * (SMW + IMW * V + ZMW * V * V)
Mvar = Load Mvar Multiplier * (SMvar + IMvar * V + ZMvar * V * V)
MW current real power load in MW
Mvar current reactive power load in Mvar
SMW constant power MW value
Smvar constant power Mvar value
IMW constant current MW value (assuming 1.0 per unit voltage)
Imvar constant current Mvar value (assuming 1.0 per unit voltage)
ZMW constant impedance MW value (assuming 1.0 per unit voltage)
Zmvar constant impedance Mvar value (assuming 1.0 per unit voltage)
V per unit bus voltage magnitude
Load MW Multiplier = (Area MW Multiplier) * (Zone MW Multiplier)
Load Mvar Multiplier = (Area Mvar Multiplier) * (Zone Mvar Multiplier)
The Area Multipliers scale all of the loads in an area. The Zone Multipliers scale all of the loads in a
zone. These are static values that do not vary over time. If a time varying schedule of loads is
required, the Time Step Simulation tool should be used instead of the static multipliers.
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