A comparison of highly coupled step-down transformers dedicated for resistance welding systems

The paper is focused on the analysis of transformers that are devoted for resistance spot welding DC machine. The analysis is carried out in order to get information about the influence of the design (shape of the cross-section of the magnetic core and also the way the windings are wounded) on the power properties of transformer (power loss and power density). The magnetic material taken into analysis is a ferrite one. The transformers are connected to two diode full-wave rectifier. Such connection requires special design of transformer - with two secondary windings. The transformers operate at 10 kHz of the frequency. Rating parameters are output current 10 kA, turn-to-turn ratio 50:1 and load resistance 0.8 mOhm.