Principle of the method

Quasi 3D (or 2½D) computations

The computations carried out with the Skew slots module of Flux is called quasi 3D (or 2½D ), as:

  • the 3D aspects of the field are taken into consideration in the thickness of the machine
  • the edge effects on one edge and the other of the machine are not modeled (the air at one edge of the machine and the other one are not represented)

Proposed method in Flux

The quasi 3D (or 2½D) computation is carried out using the method called “multilayers 2D”.

The multilayers 2D method is based on the splitting of the machine into n layers, with swinging of the layer to each other in function of the number of layers and of the slots skew angle.

Computation 2½D

Multilayers 2D

Multilayers 2D method

The multilayers 2D method is presented in details in the table below. The process starting point is the 2D description of the machine.

Phase Description
1

Construction by propagation of an assembly of n layers starting from the base faces (2D description of the machine):

  • by translation for the right part
  • by helicoidal transformation for the skewed part
2 2D computation on the set of layers (all together)
3 Computation by integration on the set of layers of all post-processed global quantities (torque, energy, …)

The right part (the skewed part) can be the rotor or stator of the motor (and vice versa).

An example of a rotor cut into slices is represented in the figure below: