If ambient temperature is known, it can be used in the applicable models. If it is not known, the
temperature difference,DT, can be set to zero. Likewise, if motor load torque is known, it can be used in
the applicable models. If it is not known, the torque difference,Dt, can be set to zero.
Based on the test results of load components and the developed real and reactive power models as
presented in these tables, the following comments on the reactive power models are important.
.The reactive power models vary significantly from manufacturer to manufacturer for the same
component. For instance, four load models of single-phase central air-conditioners show a Q=P
ratio that varies between 0 and 0.5 at 1.0 p.u. voltage. When the voltage changes, theDQ=DVof
each unit is quite different. This situation is also true for all other components, such as
refrigerators, freezers, fluorescent lights, etc.TABLE 20.1 Static Models of Typical Load Components—AC, Heat Pump, and Appliances
Load Component Static Component Model
1-fCentral Air Conditioner P¼1.0þ0.4311DVþ0.9507DTþ2.070DV^2 þ2.388DT^2 0.900DVDT
Q¼0.3152þ0.6636DVþ0.543DV^2 þ5.422DV^3 þ0.839DT^2 1.455DVDT
3-fCentral Air Conditioner P¼1.0þ0.2693DVþ0.4879DTþ1.005DV^2 0.188DT^2 0.154DVDT
Q¼0.6957þ2.3717DVþ0.0585DTþ5.81DV^2 þ0.199DT^2 0.597DVDT
Room Air Conditioner
(115V Rating)
P¼1.0þ0.2876DVþ0.6876DTþ1.241DV^2 þ0.089DT^2 0.558DVDT
Q¼0.1485þ0.3709DVþ1.5773DTþ1.286DV^2 þ0.266DT^2 0.438DVDT
Room Air Conditioner
(208=230V Rating)
P¼1.0þ0.5953DVþ0.5601DTþ2.021DV^2 þ0.145DT^2 0.491DVDT
Q¼0.4968þ2.4456DVþ0.0737DTþ8.604DV^2 0.125DT^2 1.293DVDT
3-fHeat Pump (Heating Mode) P¼1.0þ0.4539DVþ0.2860DTþ1.314DV^2 0.024DVDT
Q¼0.9399þ3.013DV0.1501DTþ7.460DV^2 0.312DT^2 0.216DVDT
3-fHeat Pump (Cooling Mode) P¼1.0þ0.2333DVþ0.5915DTþ1.362DV^2 þ0.075DT^2 0.093DVDT
Q¼0.8456þ2.3404DV0.1806DTþ6.896DV^2 þ0.029DT^2 0.836DVDT
1-fHeat Pump (Heating Mode) P¼1.0þ0.3953DVþ0.3563DTþ1.679DV^2 þ0.083DVDT
Q¼0.3427þ1.9522DV0.0958DTþ6.458DV^2 0.225DT^2 0.246DVDT
1-fHeat Pump (Cooling Mode) P¼1.0þ0.3630DVþ0.7673DTþ2.101DV^2 þ0.122DT^2 0.759DVDT
Q¼0.3605þ1.6873DVþ0.2175DTþ10.055DV^2 0.170DT^2 1.642DVDT
Refrigerator P¼1.0þ1.3958DVþ9.881DV^2 þ84.72DV^3 þ 293 DV^4
Q¼1.2507þ4.387DVþ23.801DV^2 þ 1540 DV^3 þ 555 DV^4
Freezer P¼1.0þ1.3286DVþ12.616DV^2 þ133.6DV^3 þ 380 DV^4
Q¼1.3810þ4.6702DVþ27.276DV^2 þ293.0DV^3 þ 995 DV^4
Washing Machine P¼1.0þ1.2786DVþ3.099DV^2 þ5.939DV^3
Q¼1.6388þ4.5733DVþ12.948DV^2 þ55.677DV^3
Clothes Dryer P¼1.00.1968DV3.6372DV^2 28.32DV^3
Q¼0.209þ0.5180DVþ0.363DV^2 4.7574DV^3
Television P¼1.0þ1.2471DVþ0.562DV^2
Q¼0.243lþ0.9830DVþ1.647DV^2
Fluorescent Lamp P¼1.0þ0.6534DV1.65DV^2
Q¼0.15350.0403DVþ2.734DV^2
Mercury Vapor Lamp P¼1.0þ0.1309DVþ0.504DV^2
Q¼0.2524þ2.3329DVþ7.811DV^2
Sodium Vapor Lamp P¼1.0þ0.3409DV2.389DV^2
Q¼0.060þ2.2173DVþ7.620DV^2
Incandescent P¼1.0þ1.5209DVþ0.223DV^2
Q¼0.0
Range with Oven P¼1.0þ2.1018DVþ5.876DV^2 þ1.236DV^3
Q¼0.0
Microwave Oven P¼1.0þ0.0974DVþ2.071DV^2
Q¼0.2039þ1.3130DVþ8.738DV^2
Water Heater P¼1.0þ0.3769DVþ2.003DV^2
Q¼0.0
Resistance Heating P¼1.0þ 2 DVþDV^2
Q¼0.0