Ampere’s law is invoked to calculate Hp to ensure that magnetic
flux density is reduced by α between the top surface of the
core and the top surface of the winding. In the simulation, the
flux lines follow a pattern and the corner areas are not necessarily
filled with flux; however, in the behavioral model, the flux
lines around the winding window are approximated to be rectangular
as shown in Fig. 2 to simplify the calculation. Around
closed contours l1 and l2