High frequency induction heating power supply phase tracking system based on TMS320F2812

When induction heating power supply working at high-frequency state, phase tracking is a difficulty. The paper presents a phase tracking method based on TMS320F2812 of induction heating power supply. The method uses the signal processing circuit to process the phase of voltage and current signals, and send the phase signals to capture units of TMS320F2812, and then TMS320F2812 uses fuzzy control algorithm to modify the power MOSFET switching frequency, until that the TMS320F2812 count in two capture unit of the difference is minimal. Power adjustment method is phase-shift power modulation. The paper presents the basic principle of fuzzy control algorithm and the schematic diagram of the signal processing circuit, also building experiment platform for experimental verification. According to the experiment results, we can see that the phase tracking method in this paper is effective and stable.