Optimization of open magnetic circuit motors
Linear and compound electric motors

This section focuses on linear motors.

The above considerations show that, as a result of special effects, the magnetic induction generated by both induced and induced currents has an asymmetrical distribution over the length of the air gap and variations over its width and height.

This raises two questions for the manufacturer of linear motors: what is the optimum form of induction to allow in the air gap, and how can it be imposed?

To answer the first question, we need to establish the optimization criteria and deduce the shape of the machine and the expression of the excitation field.

The most rigorous research to date has focused on linear machines for traction and positioning, where the role of parasitic distribution of the resulting fields is particularly damaging.

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