Summary for: WindingLayoutBase < handle

Class summary

WindingLayoutBase Base class for winding layouts.

The WindingLayoutBase class exists to simplify the workflow of creating the winding part of slot geometries, such as creating the necessary Materials, Surfaces, and Domains, adding Conductors to the parent PolyphaseCircuit, and so on.

Where the PolyphaseWindingSpec handles the overall winding layout, the WindingLayoutBase class focuses on everything that goes on inside the slot itself.

Ideally, the WindingLayoutBase class is used as follows. When creating the parent geometry (see Stator.create_geometry), only the Surface(s) for the winding layers are created. This can be done manually, or handled automatically by a SlotShapeBase object.

Then, either the Surfaces or the SlotShapeBase object is passed on to WindingLayoutBase.create_slot_geometry , along with the parent geometry (e.g. Stator object) and the <PolyphaseWindingSpec| object.

The create_slot_geometry method then

  • Creates all the Materials associated with the winding (e.g. conductor material) and adds them to the parent geometry.

  • Creates the required Domains and required Surfaces, and adds them to the parent geometry.
  • By default, if the winding model type ( winding_model_type property of the winding spec) is defs.stranded|, one Domain is created for each surface.

  • If the model is defs.solid , individual conductors (such as wires or bars) are created as new Surfaces and Domains. This functionality has to be subclassed.

  • Creates the required Conductors and adds them to the parent geometry. By default, only StrandedConductor or SolidConductor objects are created.

Finally, the WindingLayoutBase object contains an implementation for estimating AC conductor losses of stranded winding models. As this depends on the conductor shape (and the very mathematical approximation preferred), this funcionality has to be subclassed.

NOTE: you don’t have to use a WindingLayoutBase object. Indeed, it is totally fine to create all the required Surfaces, Materials, Domains, and Conductors manually in the create_geometry method of your parent geometry. (This might result in errors though - please contact the support if this happens.)

However, the class is intended for maximizing the reusability and interchangeability of, well, everything. For instance, if you are creating a new StatorBase subclass for some purpose, you don’t then have to separately implement functionality for modelling stranded conductors, solid bar conductors, solid wires, … - you get the point. Instead, you can externalize that tedium to the suitable WindingLayoutBase object.

Finally, a WindingLayoutBase object can be used to easily set the slot liner thickness and to access to uninsulated winding area, to evaluate packing factors etc.

USAGE: The intended usage is as follows.

Simple case : While specifying the dimensions, you set the layout_spec property of your winding spec to the layout you prefer.

*Custom case: : While creating a custom parent geometry, you either use a SlotShapeBase object and pass it on to the create_slot_geometry method, or you manually create the slot (or rather, winding) Surfaces, and pass them as an array.

Properties

.interlayer_insulation_length - linear interlayer insulation length

.interlayer_insulation_thickness Interlayer insulation thickness.

If not specified, slot liner thickness x 2 is returned.

.mesh_liner - Mesh slot liner or not?

.slot - a SlotShapeBase object associated with this

.slot_liner_length - linear slot liner length

.slot_liner_thickness - slot liner thickness (m)

.winding_spec - a PolyphaseWindingSpec object of the parent circuit

.winding_window_area - winding window area, gross

Methods

Class methods are listed below. Inherited methods are not included.

.check_surface_count Check the number of winding window

surfaces.

.compute_losses_stranded Estimate AC losses in stranded windings.

Estimate AC loss distribution for stranded (= non-solid) conductor models.

[p_el, data] = compute_losses_stranded(this, winding_spec, dBx, dBy, conductivity), where

  • winding_spec : PolyphaseWindingSpec object for specifying the winding.

  • dBx, dBy : time-derivative of flux density

  • conductivity : electrical conductivity, assumed uniform.

See the code of PolyphaseCircuit.stranded_conductor_losses for more details.

.conductor_area Total conductor area per slot.

Returns nan by default; should be overridden in subclasses if needed.

.create_and_add_insulator_material Create insulator Material.

m = create_and_add_insulator_material(this, parent_geometry) creates and adds the slot insulation material to the parent geometry, using the parent_geometry.create_and_add_material method. By default, generic resin material 26 is used.

If the parent geometry has a dimension ‘slot_insulation_material’, that is used instead.

.WindingLayoutBase/create_custom_geometry is a function.

create_custom_geometry(this, parent_geometry, winding_spec, surfaces)

.create_slot_geometry Create the winding geometry.

This method creates the winding geometry, creating the necessary Material and Domain objects and adding them to the parent_geometry . In addition, it creates the required Conductor s specified by the winding_spec.winding_model_type property, and adds them to the PolyphaseCircuit specified by winding_spec.circuit property.

Call syntax:

[] = create_slot_geometry(this, parent_geometry, winding_spec, slot_or_surfaces), where

Depending on the winding model, this method calls either the create_stranded_geometry or create_solid_geometry methods. Custom cases must be subclassed.

.create_solid_geometry Create slot geometry for solid winding

models.

.create_stranded_geometry Finalize slot geometry of stranded windings.

.gross_conductor_area Conductor area WITH insulation.

Returns the gross conductor area: useful area plus insulation, per single conductor. Returns nan by default, should be subclassed.

.parse_slot_data Parse slot area, liner/insulation lengths.

.uninsulated_winding_area Winding window area minus liners.