| Title |
Design of Line-frequency Noise Suppression Circuit to Suppress Audible Noise Considering Input Harmonic Standards in Domestic IH Systems |
| Authors |
Jeong-Hyo Lee ; Jun-Suk Lee ; Jee-Hoon Jung |
| DOI |
https://doi.org/10.6113/TKPE.2026.31.3.265 |
| ISSN |
1229-2214(pISSN), 2288-6281(eISSN) |
| Keywords |
Induction heating (IH) systems; Line-frequency noise suppression (LNS) circuit; Audible noise; Harmonic standards |
| Abstract |
The use of induction heating (IH) systems is increasing due to their high efficiency and rapid heating speed, but they suffer from various noises during operation. Among such noises, audible noise is generated by the rectified system frequency and is proportional to the amount of variation in the resonant current. Recently, this line-frequency-induced noise problem has become significant as the market demands higher output power. IH systems that combine a line-frequency noise suppressor (LNS) circuit connected to the input stage of the inverter have been the subject of research in an effort to reduce this noise. The LNS circuit reduces line-frequency-induced noise by decreasing the variation in the resonant current through partial power transfer. However, introducing an auxiliary circuit distorts the input current waveform, failing to meet harmonic standards (e.g., IEC 61000-3-2). Therefore, this research presents a modeling approach for the input current and an LNS circuit design methodology based on this model to meet the harmonic standards. The performance of the proposed method is verified through experiments using a 2 kW half-bridge series resonant inverter and an LNS circuit prototype. |