Load Characteristic Model: MOTORW

 

Following checks and corrections are applied during Validation and AutoCorrection.

  • If 0 < Tpo < Mult*TimeStep then Tpo = Mult*TimeStep
  • If 0.0 < Tppo < 0.5*Mult*TimeStep then Tppo = 0, ElseIf 0.5*Mult*TimeStep < Tppo < Mult*TimeStep then Tppo = Mult*TimeStep
  • If H < 0.01 then H = 0.01.
  • Pul: This is a normalized value, thus check if greater than 1, or less than 0; this catches a user ending a percentage value but do not autocorrect the value.
  • If Lp > 0.4*Ls then Lp = 0.4*Ls
  • If Lpp > Lp then Lpp = Lp

Mult represents the user-specified value Minimum time constant size as multiple of time step option on the Validation page of the Transient Stability Dialog

TimeStep represents the integration time step being used as described on TimeStep

Model Equations and/or Block Diagrams

Parameters:

Mbase MBase: MBase of Load Model
ApplyToConstantPowerOnly 0 means it applies to all, 1 means it applies to only the constant power part of the load
Pul Fraction of constant-power load to be represented by this motor model (between 1.0 and 0.0)
Ls Synchronous reactance
Lp Transient reactance
Ra Stator resistance, p.u.
Tpo Transient rotor time constant
H Inertia constant, sec.
D Damping factor, p.u.
VT Voltage threshold for tripping (default = 0), p.u.
TV Voltage trip pickup time (default = 999), sec.
Tbkr Circuit breaker operating time (default = 999), sec.
Acc Acceleration factor for initialization
Lpp Sub-transient reactance, p.u.
Tppo Sub-transient rotor time constant, sec.
ndelt Time step subdivision factor.
wdelt Speed threshold for subdividing time step, p.u.