In the stacked core transformer, the iron core mainly has the following two functions: 1. As a central medium of electromagnetic conversion, the primary side of the energy conversion to the secondary side; 2. 2. As a supporting skeleton for the coil and body.

Loss reduction can be considered from the following directions: 1. Choose high quality iron core, such as cold rolled silicon steel sheet with lower unit loss or amorphous alloy iron core; 2. 2. Excellent stacking process to prevent the iron core from being stressed too much or too small (amorphous alloy iron core can not be stressed); 3. Reduce the number of joints, increase the joint area, increase the lamination series, choose oblique joints and other methods to expand the joint area, reduce the magnetic damage at the joint; 4. Properly reduce the magnetic density of the core accounting