Full-Bridge Current Source Inverter Using Pulse Density Control for Induction Preheating of Welding Application

This paper presents an application for industrial induction heating with the ZCS-PDM technology, which is proposed to use a parallel resonant current source inverter. The output power of ZCS-PDM can be controlled by adjusting the pulse density modulation of the square-wave. The inverter has the lowest voltage. The switching loss can be operated under zero-current switching (ZCS). This technique is used to determine the characteristics of materials above normal temperature during the no-load in induction coil. Both circuits are studied and designed using computer modeling. The simulation and experimental results of the circuits may be obtained by adjusting the switch frequency of the buck converter at 16.66 Hz and the inverter at 16.66 kHz. A 300 x 500 x 35 millimeters SS400 steel plate was heated to the appropriate temperature during testing utilizing a 1 kW output power.