Load Characteristic Model: CMPLDW
AutoCorrection Properties
Following checks and corrections are applied during Validation and AutoCorrection.
- If Vmax < Vmin then swap the values. If Vmax < 0 then Vmax change sign to positive. Also if Vmin < 0.96 then Vmin = 0.96; and also if Vmax < 0.96 then Vmax = 0.96
- Mtypa, Mtypb, Mtypc and Mtypd: Must be either 1 or 3. This is an error and do not autocorrect the values.
- FmA, FmB, FmC, FmD and Fel: Summation of (FmA + FmB + FmC + FmD + Fel) must be less or equal than 1.0, and if not then the values will be normalized so that sum equals 1.0.
- For Motor Type 1 Motors (LD1PAC):
- If 0.0 < Tv < 0.5*Mult*TimeStep then Tv = 0, ElseIf 0.5*Mult*TimeStep < Tv < Mult*TimeStep then Tv = Mult*TimeStep
- If 0.0 < Tth < 0.5*Mult*TimeStep then Tth = 0, ElseIf 0.5*Mult*TimeStep < Tth < Mult*TimeStep then Tth = Mult*TimeStep
- If 0.0 < Frst < 0.5*Mult*TimeStep then Frst = 0, ElseIf 0.5*Mult*TimeStep < Frst < Mult*TimeStep then Frst = Mult*TimeStep
- If 0.0 < CompPF < 0.01*Mult*TimeStep then CompPF = 0.0
ElseIf 0.01*Mult*TimeStep < CompPF < Mult*TimeStep then CompPF = Mult*TimeStep
- For Motor Type 3 Motors (MOTOR_CMP):
- If 0 < Tpo < Mult*TimeStep then Tpo = Mult*TimeStep
- If H < 0.01 then H = 0.01.
- 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: Determines how the distribution equivalent MVABase is calculated for loads. Mbase>0 means DistMVABase = Mbase; Mbase<0 means DistMVABase = LoadMW/abs(Mbase); Mbase=0 means DistMVABase = LoadMW/0.8; Each load record can override this by specifying the TSDistEquivMVABase directly as well. |
| Bss | Bss: Substation shunt capacitor susceptance, p.u. |
| Rfdr | Rfdr: Feeder equivalent resistance, p.u. |
| Xfdr | Xfdr: Feeder equivalent reactance, p.u. |
| Fb | Fb: Fraction of feeder shunt capacitance at substation bus end |
| Xxf | Xxf: Substation transformer reactance, p.u. |
| Tfixhs | Tfixhs: Transformer high side fixed tap, p.u. |
| Tfixls | Tfixls: Transformer low side fixed tap, p.u. |
| LTC | LTC: 1 for automatic tap adjustment (low side variable tap) |
| Tmin | Tmin: Minimum variable tap, p.u. |
| Tmax | Tmax: Maximum variable tap, p.u. |
| step | step: Variable tap step size, p.u. |
| Vmin | Vmin: Minimum low-side voltage, p.u. |
| Vmax | Vmax: Maximum low-side voltage, p.u. |
| Tdel | Tdel: Time delay to initiate tap adjustment, sec. |
| Tdelstep | Tdelstep: Time delay between tap steps, sec. |
| Rcmp | Rcmp: Transformer LTC compensating resistance, p.u. |
| Xcmp | Xcmp: Transformer LTC compensating reactance, p.u. |
| FmA | FmA: Motor A fraction of load P |
| FmB | FmB: Motor B fraction of load P |
| FmC | FmC: Motor C fraction of load P |
| FmD | FmD: Motor D fraction of load P |
| Fel | Fel: Electronic load fraction of load P |
| PFel | PFel: Electronic load power factor |
| Vd1 | Vd1: Voltage below which electronic load decreases, p.u. |
| Vd2 | Vd2: Voltage below which electronic load is zero, p.u. |
| frcel | frcel : Fraction of electronic load that recovers from low voltage trip |
| PFs | PFs: Power factor of static load component |
| P1e | P1e: Static load – exponent of first P term |
| P1c | P1c: Static load – coefficient of first P term |
| P2e | P2e: Static load – exponent of second P term |
| P2c | P2c: Static load – coefficient of second P term |
| Pfrq | Pfrq: Frequency sensitivity factor for P |
| Q1e | Q1e: Static load – exponent of first Q term |
| Q1c | Q1c: Static load – coefficient of first Q term |
| Q2e | Q2e: Static load – exponent of second Q term |
| Q2c | Q2c: Static load – coefficient of second Q term |
| Qfrq | Qfrq: Frequency sensitivity factor for Q |
| Mtypa | Mtypa: Motor A type |
| Mtypb | Mtypb: Motor B type |
| Mtypc | Mtypc: Motor C type |
| Mtypd | Mtypd: Motor D type |
| LFma | (Type 3) LFma: Motor loading factor, (Type 1) LFma: Motor loading factor |
| Rsa_CompPFa | (Type 3) Rsa: Stator resistance, p.u., (Type 1) CompPFa: Power Factor |
| Lsa_Vstalla | (Type 3) Lsa: Synchronous reactance, p.u., (Type 1) Vstalla: Stall voltage, p.u. |
| Lpa_Rstalla | (Type 3) Lpa: Transient reactance, p.u., (Type 1) Rstalla: Stall resistance, p.u. |
| Lppa_Xstalla | (Type 3) Lppa: Subtransient reactance, p.u., (Type 1) Xstalla: Stall reactance, p.u. |
| Tpoa_Tstalla | (Type 3) Tpoa: Transient open circuit time constant, sec., (Type 1) Tstalla: Stall time delay, sec. |
| Tppoa_Frsta | (Type 3) Tppoa: Subtransient open circuit time constant, sec., (Type 1) Frsta: Fraction of load that can restart after stalling |
| Ha_Vrsta | (Type 3) Ha: Inertia constant, sec., (Type 1) Vrsta: Voltage at which restart can occur, p.u. |
| Etrqa_Trsta | (Type 3) Etrqa: Mechanical torque exponent, (Type 1) Trsta: Restart time delay, sec. |
| Vtr1a_Fuvra | (Type 3) Vtr1a: First low voltage trip level, p.u. V, (Type 1) Fuvra: Fraction of load with undervoltage relay protection |
| Ttr1a_Vtr1a | (Type 3) Ttr1a: First low voltage trip delay time, sec., (Type 1) Vtr1a: First undervoltage trip level, p.u. |
| Ftr1a_TTr1a | (Type 3) Ftr1a: First low voltage trip fraction, (Type 1) Ttr1a: First undervoltage trip delay time, sec. |
| Vrc1a_Vtr2a | (Type 3) Vrc1a: First low voltage reconnection level, p.u. V, (Type 1) Vtr2a: Second undervoltage trip level, p.u. |
| Trc1a_Ttr2a | (Type 3) Trc1a: First low voltage reconnection delay time, sec., (Type 1) Ttr2a: Second undervoltage trip delay time, sec. |
| Vtr2a_Vc1offa | (Type 3) Vtr2a: Second low voltage trip level, p.u. V, (Type 1) Vc1offa: Contactor voltage at which tripping starts, p.u. |
| Ttr2a_Vc2offa | (Type 3) Ttr2a: Second low voltage trip delay time, sec., (Type 1) Vc2offa: Contactor voltage at which tripping is complete, p.u. |
| Ftr2a_Vc1ona | (Type 3) Ftr2a: Second low voltage trip fraction, (Type 1) Vc1ona: Contactor voltage at which reconnection is complete, p.u. |
| Vrc2a_Vc2ona | (Type 3) Vrc2a: Second low voltage reconnection level, p.u. V, (Type 1) Vc2ona: Contactor voltage at which reconnection starts, p.u. |
| Trc2a_Ttha | (Type 3) Trc2a: Second low voltage reconnection time delay, sec., (Type 1) Ttha: Thermal time constant, sec. |
| Th1ta | (Type 1) Th1ta: Thermal protection trip start level, p.u. temperature |
| Th2ta | (Type 1) Th2ta: Thermal protection trip completion level, p.u. temperature |
| Tva | (Type 1) Tva: Voltage measurement lag, sec. |
| LFmb | (Type 3) LFmb: Motor loading factor, (Type 1) LFmb: Motor loading factor |
| Rsb_CompPFb | (Type 3) Rsb: Stator resistance, p.u., (Type 1) CompPFb: Power Factor |
| Lsb_Vstallb | (Type 3) Lsb: Synchronous reactance, p.u., (Type 1) Vstallb: Stall voltage, p.u. |
| Lpb_Rstallb | (Type 3) Lpb: Transient reactance, p.u., (Type 1) Rstallb: Stall resistance, p.u. |
| Lppb_Xstallb | (Type 3) Lppb: Subtransient reactance, p.u., (Type 1) Xstallb: Stall reactance, p.u. |
| Tpob_Tstallb | (Type 3) Tpob: Transient open circuit time constant, sec., (Type 1) Tstallb: Stall time delay, sec. |
| Tppob_Frstb | (Type 3) Tppob: Subtransient open circuit time constant, sec., (Type 1) Frstb: Fraction of load that can restart after stalling |
| Hb_Vrstb | (Type 3) Hb: Inertia constant, sec., (Type 1) Vrstb: Voltage at which restart can occur, p.u. |
| Etrqb_Trstb | (Type 3) Etrqb: Mechanical torque exponent, (Type 1) Trstb: Restart time delay, sec. |
| Vtr1b_Fuvrb | (Type 3) Vtr1b: First low voltage trip level, p.u. V, (Type 1) Fuvrb: Fraction of load with undervoltage relay protection |
| Ttr1b_Vtr1b | (Type 3) Ttr1b: First low voltage trip delay time, sec., (Type 1) Vtr1b: First undervoltage trip level, p.u. |
| Ftr1b_TTr1b | (Type 3) Ftr1b: First low voltage trip fraction, (Type 1) Ttr1b: First undervoltage trip delay time, sec. |
| Vrc1b_Vtr2b | (Type 3) Vrc1b: First low voltage reconnection level, p.u. V, (Type 1) Vtr2b: Second undervoltage trip level, p.u. |
| Trc1b_Ttr2b | (Type 3) Trc1b: First low voltage reconnection delay time, sec., (Type 1) Ttr2b: Second undervoltage trip delay time, sec. |
| Vtr2b_Vc1offb | (Type 3) Vtr2b: Second low voltage trip level, p.u. V, (Type 1) Vc1offb: Contactor voltage at which tripping starts, p.u. |
| Ttr2b_Vc2offb | (Type 3) Ttr2b: Second low voltage trip delay time, sec., (Type 1) Vc2offb: Contactor voltage at which tripping is complete, p.u. |
| Ftr2b_Vc1onb | (Type 3) Ftr2b: Second low voltage trip fraction, (Type 1) Vc1onb: Contactor voltage at which reconnection is complete, p.u. |
| Vrc2b_Vc2onb | (Type 3) Vrc2b: Second low voltage reconnection level, p.u. V, (Type 1) Vc2onb: Contactor voltage at which reconnection starts, p.u. |
| Trc2b_Tthb | (Type 3) Trc2b: Second low voltage reconnection time delay, sec., (Type 1) Tthb: Thermal time constant, sec. |
| Th1tb | (Type 1) Th1tb: Thermal protection trip start level, p.u. temperature |
| Th2tb | (Type 1) Th2tb: Thermal protection trip completion level, p.u. temperature |
| Tvb | (Type 1) Tvb: Voltage measurement lag, sec. |
| LFmc | (Type 3) LFmc: Motor loading factor, (Type 1) LFmc: Motor loading factor |
| Rsc_CompPFc | (Type 3) Rsc: Stator resistance, p.u., (Type 1) CompPFc: Power Factor |
| Lsc_Vstallc | (Type 3) Lsc: Synchronous reactance, p.u., (Type 1) Vstallc: Stall voltage, p.u. |
| Lpc_Rstallc | (Type 3) Lpc: Transient reactance, p.u., (Type 1) Rstallc: Stall resistance, p.u. |
| Lppc_Xstallc | (Type 3) Lppc: Subtransient reactance, p.u., (Type 1) Xstallc: Stall reactance, p.u. |
| Tpoc_Tstallc | (Type 3) Tpoc: Transient open circuit time constant, sec., (Type 1) Tstallc: Stall time delay, sec. |
| Tppoc_Frstc | (Type 3) Tppoc: Subtransient open circuit time constant, sec., (Type 1) Frstc: Fraction of load that can restart after stalling |
| Hc_Vrstc | (Type 3) Hc: Inertia constant, sec., (Type 1) Vrstc: Voltage at which restart can occur, p.u. |
| Etrqc_Trstc | (Type 3) Etrqc: Mechanical torque exponent, (Type 1) Trstc: Restart time delay, sec. |
| Vtr1c_Fuvrc | (Type 3) Vtr1c: First low voltage trip level, p.u. V, (Type 1) Fuvrc: Fraction of load with undervoltage relay protection |
| Ttr1c_Vtr1c | (Type 3) Ttr1c: First low voltage trip delay time, sec., (Type 1) Vtr1c: First undervoltage trip level, p.u. |
| Ftr1c_TTr1c | (Type 3) Ftr1c: First low voltage trip fraction, (Type 1) Ttr1c: First undervoltage trip delay time, sec. |
| Vrc1c_Vtr2c | (Type 3) Vrc1c: First low voltage reconnection level, p.u. V, (Type 1) Vtr2c: Second undervoltage trip level, p.u. |
| Trc1c_Ttr2c | (Type 3) Trc1c: First low voltage reconnection delay time, sec., (Type 1) Ttr2c: Second undervoltage trip delay time, sec. |
| Vtr2c_Vc1offc | (Type 3) Vtr2c: Second low voltage trip level, p.u. V, (Type 1) Vc1offc: Contactor voltage at which tripping starts, p.u. |
| Ttr2c_Vc2offc | (Type 3) Ttr2c: Second low voltage trip delay time, sec., (Type 1) Vc2offc: Contactor voltage at which tripping is complete, p.u. |
| Ftr2c_Vc1onc | (Type 3) Ftr2c: Second low voltage trip fraction, (Type 1) Vc1onc: Contactor voltage at which reconnection is complete, p.u. |
| Vrc2c_Vc2onc | (Type 3) Vrc2c: Second low voltage reconnection level, p.u. V, (Type 1) Vc2onc: Contactor voltage at which reconnection starts, p.u. |
| Trc2c_Tthc | (Type 3) Trc2c: Second low voltage reconnection time delay, sec., (Type 1) Tthc: Thermal time constant, sec. |
| Th1tc | (Type 1) Th1tc: Thermal protection trip start level, p.u. temperature |
| Th2tc | (Type 1) Th2tc: Thermal protection trip completion level, p.u. temperature |
| Tvc | (Type 1) Tvc: Voltage measurement lag, sec. |
| LFmd | (Type 3) LFmd: Motor loading factor, (Type 1) LFmd: Motor loading factor |
| Rsd_CompPFd | (Type 3) Rsd: Stator resistance, p.u., (Type 1) CompPFd: Power Factor |
| Lsd_Vstalld | (Type 3) Lsd: Synchronous reactance, p.u., (Type 1) Vstalld: Stall voltage, p.u. |
| Lpd_Rstalld | (Type 3) Lpd: Transient reactance, p.u., (Type 1) Rstalld: Stall resistance, p.u. |
| Lppd_Xstalld | (Type 3) Lppd: Subtransient reactance, p.u., (Type 1) Xstalld: Stall reactance, p.u. |
| Tpod_Tstalld | (Type 3) Tpod: Transient open circuit time constant, sec., (Type 1) Tstalld: Stall time delay, sec. |
| Tppod_Frstd | (Type 3) Tppod: Subtransient open circuit time constant, sec., (Type 1) Frstd: Fraction of load that can restart after stalling |
| Hd_Vrstd | (Type 3) Hd: Inertia constant, sec., (Type 1) Vrstd: Voltage at which restart can occur, p.u. |
| Etrqd_Trstd | (Type 3) Etrqd: Mechanical torque exponent, (Type 1) Trstd: Restart time delay, sec. |
| Vtr1d_Fuvrd | (Type 3) Vtr1d: First low voltage trip level, p.u. V, (Type 1) Fuvrd: Fraction of load with undervoltage relay protection |
| Ttr1d_Vtr1d | (Type 3) Ttr1d: First low voltage trip delay time, sec., (Type 1) Vtr1d: First undervoltage trip level, p.u. |
| Ftr1d_TTr1d | (Type 3) Ftr1d: First low voltage trip fraction, (Type 1) Ttr1d: First undervoltage trip delay time, sec. |
| Vrc1d_Vtr2d | (Type 3) Vrc1d: First low voltage reconnection level, p.u. V, (Type 1) Vtr2d: Second undervoltage trip level, p.u. |
| Trc1d_Ttr2d | (Type 3) Trc1d: First low voltage reconnection delay time, sec., (Type 1) Ttr2d: Second undervoltage trip delay time, sec. |
| Vtr2d_Vc1offd | (Type 3) Vtr2d: Second low voltage trip level, p.u. V, (Type 1) Vc1offd: Contactor voltage at which tripping starts, p.u. |
| Ttr2d_Vc2offd | (Type 3) Ttr2d: Second low voltage trip delay time, sec., (Type 1) Vc2offd: Contactor voltage at which tripping is complete, p.u. |
| Ftr2d_Vc1ond | (Type 3) Ftr2d: Second low voltage trip fraction, (Type 1) Vc1ond: Contactor voltage at which reconnection is complete, p.u. |
| Vrc2d_Vc2ond | (Type 3) Vrc2d: Second low voltage reconnection level, p.u. V, (Type 1) Vc2ond: Contactor voltage at which reconnection starts, p.u. |
| Trc2d_Tthd | (Type 3) Trc2d: Second low voltage reconnection time delay, sec., (Type 1) Tthd: Thermal time constant, sec. |
| Th1td | (Type 1) Th1td: Thermal protection trip start level, p.u. temperature |
| Th2td | (Type 1) Th2td: Thermal protection trip completion level, p.u. temperature |
| Tvd | (Type 1) Tvd: Voltage measurement lag, sec. |
