Development of 5 kVA Inductive Heating System

An inductive heating of system (IHS) of 5 kVA has been developed for heating and melting material that their temperature is below 900oC. The IHS consist of the following units: three phase rectifier, microcontroller base varying frequency generator, MOSFET driver (IR2110), array of MOSFET bridge inverter, and inductive-capacitor resonant tank. The frequency generated can vary from 5 kHz to 1 MHz. The power supply to system was obtained from three phase rectifier and properly with high capacitance value. The MOSFET driver and MOSFET bridge inverter was connected a load comprises of inductive-capacitor resonant tank. The inductance value is 3.3 µH and capacitance value is 2.2 µF but practically obtained 2.0 µF at resonant frequency of 51.5 kHz. The result of testing and performance evaluation of the fabricated IHS carried out under open laboratory environmental condition produced were: heated iron rod to red up to 856 oC in 12 minutes at frequency of 51.5 kHz, coil current 82 A and coil voltage of 48 V; and 1.5 kg of cast Al block with Al flex was melted and temperature rise to 670oC after 42 minutes of inductive heating at frequency of 51.5 kHz, average coil current of 82 A and coil voltage of 48 V.