Effects of saturation on ring head fields

Analytical expressions for ring head fields were developed which include the effects of head material saturation. These expressions were developed by fitting to computer calculations of saturated head fields after a large-scale model verified both the finite element and finite difference computer models. The x field component of the saturated head showed a very constant shape near the gap with varying side tails as a function of saturating current and gap geometry. The y field component saturates sooner than the x field component. The results can be used in recording models using ring heads from linear operation through increasing stages of pole tip saturation