Core

Model of core losses

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

Core losses can be separated into eddy current and hysteresis losses. The total core losses can thus be expressed as

P = PRef * (ratioHysteresis * (wRef / w) + 1 - ratioHysteresis) * (V / VRef)^2

where w is the actual angular remagnetization velocity and V is the actual voltage. The term ratioHysteresis is the ratio of the hysteresis losses with respect to the total core losses for the reference voltage and frequency.

In the current implementation hysteresis losses are not considered since complex numbers are not provided in Modelica. Therefore, implicitly ratioHysteresis = 0 is set. For the voltage and frequency range with respect to Fig. 1, the dependency of total core losses on the parameter ratioHysteresis is depicted in Fig. 2. The current implementation has thus the drawback over a model that considers ratioHysteresis > 0:

  • underestimation of the losses in the constant field region (w < wRef)
  • overestimation of the losses in the field weakening region (w > wRef)
corelossesVw.png
Fig. 1: Voltage versus angular velocity
corelossesPcw.png
Fig. 2: Core losses versus angular velocity with parameter ratioHysteresis

Note

In the current implementation it is assumed that ratioHysteresis = 0. This parameter cannot be changed due to compatibility reasons.

See also

Core loss parameters

Parameters (4)

useHeatPort

Value: false

Type: Boolean

Description: = true, if heatPort is enabled

coreParameters

Value:

Type: CoreParameters

Description: Core parameters

m

Value: coreParameters.m

Type: Integer

Description: Number of phases

turnsRatio

Value:

Type: Real

Description: Effective number of stator turns / effective number of rotor turns (if used as rotor core)

Inputs (1)

w

Type: AngularVelocity (rad/s)

Description: Remagnetization angular velocity

Connectors (2)

heatPort

Type: HeatPort_a

Description: Optional port to which dissipated losses are transported in form of heat

spacePhasor

Type: SpacePhasor

Components (1)

coreParameters

Type: CoreParameters

Description: Core parameters

Used in Components (2)

IM_SlipRing

Modelica.Electrical.Machines.BasicMachines.InductionMachines

Induction machine with slipring rotor

PartialBasicInductionMachine

Modelica.Electrical.Machines.Interfaces

Partial model for induction machine