Constraints

Introduction

In the data tree of Flux the node Solver > Optimization > Constraints allows the user to define some constraints which are structural or physical limitations imposed by the optimizer, a constraint allow the user to control the shape of the design with some symmetries constraints, volume values constraints or physical limits. The short list of the constraints is given below:

Table 1. Table summarizing all the constraints available in Flux
Constraints	Required informations
Constraints on 2D faces volume	A common percentage factor of variation Figure 1. Vmax and Vmin are the upper and lower bounds, p_var the common factor A percentage factor for the lower bound and another factor for the upper bound, Figure 2. Vmax and Vmin are the upper and lower bounds, p_max and p_min the factors for the upper and lower bounds The values for lower and upper bounds Figure 3. Vmax and Vmin are the upper and lower bounds, p_max and p_min the values for the upper and lower bounds
Double symmetry constraint	The origin of the symmetry axis, The direction of one of the axis, the second axis is automatically taken perpendicular to the first one. Figure 4. Origin point and double symmetry axis over an electromagnetic device In this case, only one of both axis must be defined, choose between (1;0) for X axis or (0;1) for Y axis.
Symmetry constraint	The origin of the symmetry axis, The direction of the axis, Figure 5. Origin point and a simple symmetry axis over the rotor of a rotating machine In this case, the direction of the symmetry axis is (0.5;0.5)
Physical constraint	Select a Predefined function Or a Compose function which requires: A Compose type file The name of the function related to the constraint Select the input responses which are described as physical depending reponses. Lower or an upper bound in the same unit as the response (both are not mandatory)