.Modelica.Magnetic.FundamentalWave.UsersGuide.WindingModel

Information

The SymmetricPolyphaseWinding model shown in Fig. 1 has an electric circuit with m phase currents and voltages and a magnetic circuit with the phasors representing the fundamental wave of magnetic potential and magnetic flux.

Fig. 1: Symmetric polyphase winding

Electric circuit

The electric circuit models consists of the (temperature dependent) resistances of the m phases and the zero inductance, i.e., induced voltages caused by the derivative of the sum of all phase currents (in case the sum of the currents is not zero).

Electromagnetic coupling

The PolyphaseElectroMagneticConverter calculates the magnetic voltages (MMF) caused by the currents of the m phases according to the spatial orientation of the phases. To complete the coupling, the induced voltages caused by the derivative of magentic flux are calculated, again according to the spatial orientation of the phases.

Magnetic circuit

The magnetic circuit models individual and common stray (leakage) flux as well as core loss. Note that up to now only the eddy current loss is taken into account, since the hysteresis loss require the detection of the re-magnetization frequency.

Individual and common stray field (leakage) is modeled as permeances (see Fig. 1): The parameter 0 ≤ ratioCommonLeakage ≤ 1 describes the discrimination in common and individual stray field. Note that for ratioCommonLeakage > 1 - eps the individual part is conditionally removed, whereas for ratioCommonLeakage < eps the common part is conditionally removed.

Note that for machines with three phases and for quasi-static machines the parameter ratioCommonLeakage has no influence. Feeding polyphase machines with more than three phases by switching power electronics, this discrimination is essential. Therefore the split stray field representation is only modeled in the FundamentalWave library.

The parameter ratioCommonLeakage has a default of 1, which is perfectly backwards compatible.

Note

For a model with ratioCommonLeakage < 1 - eps (including individual stray inductances) typically more states have to be initialized than for a model with ratioCommonLeakage = 1 (without individual stray inductances). See: initial equation section of example IMC_DOL_CommonLeakage, which compares the behaviour of three identical machines except ratioCommonLeakage={0, 0.5, 1}.