modelIM_SquirrelCage

Induction machine with squirrel cage rotor

Extends from Machines.Interfaces.PartialBasicInductionMachine (Partial model for induction machine).

Information

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 0.29kg.m2
rotor's moment of inertia 0.29kg.m2
nominal frequency fNominal 50Hz
nominal voltage per phase 100V RMS
nominal current per phase 100A RMS
nominal torque 161.4Nm
nominal speed 1440.45rpm
nominal mechanical output 24.346kW
efficiency 92.7%
power factor 0.875
stator resistance 0.03Ohm per phase at reference temperature
reference temperature TsRef 20°C
temperature coefficient alpha20s 01/K
rotor resistance 0.04Ohm at reference temperature
reference temperature TrRef 20°C
temperature coefficient alpha20r 01/K
stator reactance Xs 3Ohm per phase
rotor reactance Xr 3Ohm
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

TypeNameDefaultDescription
Integerm (from PartialBasicInductionMachine)3Number of phases
Integerp (from PartialBasicInductionMachine)Number of pole pairs (Integer)
SI.FrequencyfsNominal (from PartialBasicInductionMachine)Nominal frequency
BooleanuseZeroSystem (from PartialBasicInductionMachine)true= true, if zero current is explicitely computed
SI.InertiaJr (from PartialBasicMachine)Rotor's moment of inertia
BooleanuseSupport (from PartialBasicMachine)falseEnable / disable (=fixed stator) support
SI.InertiaJs (from PartialBasicMachine)JrStator's moment of inertia
BooleanuseThermalPort (from PartialBasicMachine)falseEnable / disable (=fixed temperatures) thermal port
Operational temperatures
SI.TemperatureTsOperational (from PartialBasicInductionMachine)Operational temperature of stator resistance
SI.TemperatureTrOperationalOperational temperature of rotor resistance
Nominal resistances and inductances
SI.ResistanceRs (from PartialBasicInductionMachine)Stator resistance per phase at TRef
SI.TemperatureTsRef (from PartialBasicInductionMachine)Reference temperature of stator resistance
Machines.Thermal.LinearTemperatureCoefficient20alpha20s (from PartialBasicInductionMachine)Temperature coefficient of stator resistance at 20 degC
SI.InductanceLszero (from PartialBasicInductionMachine)LssigmaStator zero sequence inductance
SI.InductanceLssigma (from PartialBasicInductionMachine)Stator stray inductance per phase
SI.InductanceLmStator main field inductance per phase
SI.InductanceLrsigmaRotor stray inductance per phase (equivalent three-phase winding)
SI.ResistanceRrRotor resistance per phase (equivalent three-phase winding) at TRef
SI.TemperatureTrRefReference temperature of rotor resistance
Machines.Thermal.LinearTemperatureCoefficient20alpha20rTemperature coefficient of rotor resistance at 20 degC
Losses
Machines.Losses.FrictionParametersfrictionParameters (from PartialBasicMachine)Friction loss parameter record
Machines.Losses.CoreParametersstatorCoreParameters (from PartialBasicInductionMachine)Stator core loss parameter record; all parameters refer to stator side
Machines.Losses.StrayLoadParametersstrayLoadParameters (from PartialBasicInductionMachine)Stray load loss parameter record

Connectors

TypeNameDefaultDescription
Modelica.Mechanics.Rotational.Interfaces.Flange_aflange (from PartialBasicMachine)Shaft
Modelica.Mechanics.Rotational.Interfaces.Flange_asupport (from PartialBasicMachine)Support at which the reaction torque is acting
Modelica.Electrical.Polyphase.Interfaces.PositivePlugplug_sp (from PartialBasicInductionMachine)Positive stator plug
Modelica.Electrical.Polyphase.Interfaces.NegativePlugplug_sn (from PartialBasicInductionMachine)Negative stator plug
Machines.Interfaces.InductionMachines.PartialThermalPortInductionMachinesthermalPort (from PartialBasicInductionMachine)

Components

TypeNameDefaultDescription
SI.AnglephiMechanical (from PartialBasicMachine)flange.phi - internalSupport.phiMechanical angle of rotor against stator
SI.AngularVelocitywMechanical (from PartialBasicMachine)der(phiMechanical)Mechanical angular velocity of rotor against stator
SI.TorquetauElectrical (from PartialBasicMachine)inertiaRotor.flange_a.tauElectromagnetic torque
SI.TorquetauShaft (from PartialBasicMachine)-flange.tauShaft torque
Modelica.Mechanics.Rotational.Components.InertiainertiaRotor (from PartialBasicMachine)
Modelica.Mechanics.Rotational.Components.InertiainertiaStator (from PartialBasicMachine)
Modelica.Mechanics.Rotational.Components.Fixedfixed (from PartialBasicMachine)
Machines.Losses.Frictionfriction (from PartialBasicMachine)
Machines.Interfaces.InductionMachines.PartialPowerBalanceInductionMachinespowerBalance (from PartialBasicInductionMachine)Power balance
SI.Voltage[m]vs (from PartialBasicInductionMachine)plug_sp.pin.v - plug_sn.pin.vStator instantaneous voltages
SI.Current[m]is (from PartialBasicInductionMachine)plug_sp.pin.iStator instantaneous currents
SI.Currenti_0_s (from PartialBasicInductionMachine)spacePhasorS.zero.iStator zero-sequence current
SI.Current[2]idq_ss (from PartialBasicInductionMachine)Stator space phasor current / stator fixed frame
SI.Current[2]idq_sr (from PartialBasicInductionMachine)Stator space phasor current / rotor fixed frame
SI.Current[2]idq_rs (from PartialBasicInductionMachine)Rotor space phasor current / stator fixed frame
SI.Current[2]idq_rr (from PartialBasicInductionMachine)Rotor space phasor current / rotor fixed frame
Modelica.Electrical.Polyphase.Basic.Resistorrs (from PartialBasicInductionMachine)
Machines.BasicMachines.Components.Inductorlssigma (from PartialBasicInductionMachine)
BasicMachines.Components.ZeroImpedancelszero (from PartialBasicInductionMachine)
Machines.Losses.InductionMachines.CorestatorCore (from PartialBasicInductionMachine)
Machines.SpacePhasors.Components.SpacePhasorspacePhasorS (from PartialBasicInductionMachine)
Machines.Losses.InductionMachines.StrayLoadstrayLoad (from PartialBasicInductionMachine)
Machines.Interfaces.InductionMachines.PartialThermalAmbientInductionMachinesthermalAmbient (from PartialBasicInductionMachine)
SI.Current[2]irsquirrelCageR.iRotor cage currents
Machines.BasicMachines.Components.AirGapSairGap
Machines.BasicMachines.Components.SquirrelCagesquirrelCageR