IM_SquirrelCage
Induction machine with squirrel cage rotor
Library
Modelica/Electrical/Machines/BasicMachines/InductionMachines
Description
Model of a three-phase induction machine with squirrel cage.
Resistance and stray inductance of stator is modeled directly in stator phases, then using space phasor transformation. Resistance and stray inductance of rotor's squirrel cage is modeled in two axis of the rotor-fixed coordinate system. Both together connected via a stator-fixed AirGap model. The machine models take the following loss effects into account:
- heat losses in the temperature dependent stator winding resistances
- heat losses in the temperature dependent cage resistances
- friction losses
- core losses (only eddy current losses, no hysteresis losses)
- stray load losses
Default values for machine's parameters (a realistic example) are:
| number of pole pairs p | 2 | |
| stator's moment of inertia | 0.29 | kg.m2 |
| rotor's moment of inertia | 0.29 | kg.m2 |
| nominal frequency fNominal | 50 | Hz |
| nominal voltage per phase | 100 | V RMS |
| nominal current per phase | 100 | A RMS |
| nominal torque | 161.4 | Nm |
| nominal speed | 1440.45 | rpm |
| nominal mechanical output | 24.346 | kW |
| efficiency | 92.7 | % |
| power factor | 0.875 | |
| stator resistance | 0.03 | Ohm per phase at reference temperature |
| reference temperature TsRef | 20 | °C |
| temperature coefficient alpha20s | 0 | 1/K |
| rotor resistance | 0.04 | Ohm at reference temperature |
| reference temperature TrRef | 20 | °C |
| temperature coefficient alpha20r | 0 | 1/K |
| stator reactance Xs | 3 | Ohm per phase |
| rotor reactance Xr | 3 | Ohm |
| total stray coefficient sigma | 0.0667 | |
| stator operational temperature TsOperational | 20 | °C |
| rotor operational temperature TrOperational | 20 | °C |
| These values give the following inductances: | ||
| stator stray inductance per phase | Xs * (1 - sqrt(1-sigma))/(2*pi*fNominal) | |
| rotor stray inductance | Xr * (1 - sqrt(1-sigma))/(2*pi*fNominal) | |
| main field inductance per phase | sqrt(Xs*Xr * (1-sigma))/(2*pi*fNominal) |
Parameters
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_m | m | Number of phases | Scalar | |
mo_p | p | Number of pole pairs (Integer) | Scalar | |
mo_fsNominal | fsNominal | Nominal frequency | Scalar | |
mo_Jr | Jr | Rotor's moment of inertia | Scalar | |
mo_useSupport | useSupport | Enable / disable (=fixed stator) support | Number | 0 |
mo_Js | Js | Stator's moment of inertia | Scalar | |
mo_useThermalPort | useThermalPort | Enable / disable (=fixed temperatures) thermal port | Number | 0 |
mo_TsOperational | TsOperational | Operational temperature of stator resistance | Scalar | |
mo_TrOperational | TrOperational | Operational temperature of rotor resistance | Scalar | |
mo_phiMechanical | phiMechanical | phiMechanical | Structure | |
mo_phiMechanical/fixed | fixed | Cell of scalars | true | |
mo_phiMechanical/start | start | Cell of scalars | ||
mo_wMechanical | wMechanical | wMechanical | Structure | |
mo_wMechanical/fixed | fixed | Cell of scalars | true | |
mo_wMechanical/start | start | Cell of scalars |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_Rs | Rs | Stator resistance per phase at TRef | Scalar | |
mo_TsRef | TsRef | Reference temperature of stator resistance | Scalar | |
mo_alpha20s | alpha20s | Temperature coefficient of stator resistance at 20 degC | Scalar | |
mo_Lszero | Lszero | Stator zero sequence inductance | Scalar | |
mo_Lssigma | Lssigma | Stator stray inductance per phase | Scalar | |
mo_Lm | Lm | Stator main field inductance per phase | Scalar | |
mo_Lrsigma | Lrsigma | Rotor stray inductance per phase (equivalent three-phase winding) | Scalar | |
mo_Rr | Rr | Rotor resistance per phase (equivalent three-phase winding) at TRef | Scalar | |
mo_TrRef | TrRef | Reference temperature of rotor resistance | Scalar | |
mo_alpha20r | alpha20r | Temperature coefficient of rotor resistance at 20 degC | Scalar |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_frictionParameters | frictionParameters | Friction loss parameter record | FromModelica('Modelica.Electrical.Machines.Losses.FrictionParameters') | |
mo_statorCoreParameters | statorCoreParameters | Stator core loss parameter record; all parameters refer to stator side | FromModelica('Modelica.Electrical.Machines.Losses.CoreParameters') | |
mo_strayLoadParameters | strayLoadParameters | Stray load loss parameter record | FromModelica('Modelica.Electrical.Machines.Losses.StrayLoadParameters') |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo__nmodifiers | Number of Modifiers | Specifies the number of modifiers | Number | |
mo__modifiers | Modifiers | Add new modifier | Structure | |
mo__modifiers/varname | Variable name | Cell of strings | 'tauElectrical' | |
mo__modifiers/attribute | Attribute | Cell of strings | 'start' | |
mo__modifiers/value | Value |
Ports
| Name | Type | Description | IO Type | Number |
|---|---|---|---|---|
flange | implicit | Shaft | input | 1 |
plug_sp | implicit | Positive stator plug | input | 2 |
plug_sn | implicit | Negative stator plug | output | 1 |
Port 4 | implicit | Support at which the reaction torque is acting | input | mo_useSupport |
Port 5 | implicit | input | mo_useThermalPort |