What is the formula for the depth of the yoke?

The depth of the yoke in the context of electrical machines, specifically transformers and electric motors, is determined by considering the magnetic flux it needs to carry. There isn’t a one-size-fits-all formula for the depth of the yoke because it varies based on the design requirements, including the type of core material, the magnetic flux density, and overall dimensions of the machine. However, a general approach to determining the depth (d) of the yoke can be outlined as follows:

[ d = frac{Phi}{B times l} ]

Where:

– (d) is the depth of the yoke (usually in meters),

– (Phi) is the magnetic flux (in Weber, Wb),

– (B) is the desired magnetic flux density in the yoke (in Tesla, T),

– (l) is the length of the core around which the yoke is wrapped (perimeter in the case of a circular core, or sum of sides for a rectangular core, measured in meters).

It’s crucial to choose an appropriate value of (B) to ensure that the core material operates efficiently without reaching saturation, which might vary from material to material (typically between 1.5 T to 2.0 T for common electrical steel).

For specific applications or advanced designs, including considerations for factors like thermal behavior, mechanical strength, and economic aspects, further detailed calculations and simulations might be required.