In a multiple load induction heating (IH) system, the effective voltage across particular load changes during different loading conditions. Thus, the quality of heating across the IH load degrades. Furthermore, in any IH system, a high-frequency (HF) inverter with a high switching frequency makes HF components that flow back toward the utility side and distort the waveform of the current. The constant input voltage to the IH loads with quality input current is an essential condition to generate uniform heating. To accomplish this, a load adaptive proportional integral derivation (PID)-aided asymmetrical voltage cancellation control scheme is proposed to maintain a constant voltage profile across the IH load under variable load conditions. A boost power factor correction converter has been used as a front-end converter followed by a HF full-bridge series resonant inverter to improve the utility power factor. The proposed IH system ensures unity power factor operation along with a constant voltage profile across the load, and it has been validated through the MATLAB/Simulink environment. Also, a prototype has been developed using embedded control, and its dynamic behavior has been studied under multiple IH loads. The obtained simulation and experimental results confirm the effectiveness of the proposed IH system under the aforesaid control scheme.
Cite this article as: A. Kumar and C. Kumar, "Load adaptive PID-aided asymmetrical voltage cancellation controller-based induction heating system with improved power factor," Electrica, 23(2), 385-396, 2023.