What is the formula for the maximum permissible width of slot?

The maximum permissible width of a slot, especially in the context of electrical machine design such as in the stator of an induction motor, typically relates to the minimization of slot leakage flux and the optimization of the slot fill factor. However, the exact formula or set of considerations for determining the maximum permissible width of a slot can vary depending on several design factors, including the type of machine, the operating frequency, the magnetic material used, and thermal considerations.

A generalized approach to determining the slot dimensions, including the width, often involves balancing electrical and magnetic performance with manufacturing considerations. Quantitative assessments in machine design often lean on empirical formulas derived from design standards or based on the specific requirements of the machine’s application. For instance, larger slots might be used to accommodate more winding or larger wire sizes for higher current, but this can adversely affect the magnetic performance and increase leakage flux.

One might consider aspects like the Carter’s Coefficient to account for the effect of slot opening on the magnetic flux distribution in electric machine design calculations, which indirectly influences how one might approach determining an acceptable slot width.

However, without a specific context or a more focused application (like in transformers, induction motors, or other electrical machinery), providing a universal formula for the maximum permissible width of a slot isn’t straightforward.

Typical considerations might involve:

1. Magnetic Flux Density: To ensure the core operates within its optimal magnetic saturation level and to manage the magnetic flux effectively.
2. **Current Density and Thermal