10-12-2021, 08:21 PM
Hi Adrian, a quick and dirty method to check saturation is to plot an I/V curve for the transformer at its frequency of operation, or use 50Hz and extrapolate.
The "knee point" of the curve should be quite obvious, this is where saturation is starting. It is then possible to get a turns/ volt figure to stay below saturation for that specific core.
Or, using the transformer equation N= V/ 4.44, F, B, Ae
N=turns
4.44 constant for a sine wave (4.0 for Sq wave)
F = freq
B =working flux density
Ae, cross sectional area of centre limb in M^2
For Stalloy B = 1.0, for Unisil (GOSS material) it can go as high as 1.5 and the curve into saturation is slower
Plenty of things to play about with there.
Note that on a laminated transformer the gaps between E & I lams should be tightly closed or saturation will start earlier
Ed
The "knee point" of the curve should be quite obvious, this is where saturation is starting. It is then possible to get a turns/ volt figure to stay below saturation for that specific core.
Or, using the transformer equation N= V/ 4.44, F, B, Ae
N=turns
4.44 constant for a sine wave (4.0 for Sq wave)
F = freq
B =working flux density
Ae, cross sectional area of centre limb in M^2
For Stalloy B = 1.0, for Unisil (GOSS material) it can go as high as 1.5 and the curve into saturation is slower
Plenty of things to play about with there.
Note that on a laminated transformer the gaps between E & I lams should be tightly closed or saturation will start earlier
Ed
