Most existing power supplies for induction heating equipment produce voltage at a single (adjustable) frequency. Recently, however, induction heating power supplies that produce voltage at two (adjustable) frequencies have been researched and even commercialized. Dual-frequency power supplies are a significant development for heat-treating workpieces with uneven geometries, such as gears, since different portions of such workpieces are heated dissimilarly at a single frequency and so require a two step process using a single-frequency power supply. On the other hand, a dual-frequency power supply can achieve the desired result for such workpieces in a one step process. However, the existing approaches to dual-frequency voltage generation could be improved to achieve higher efficiency, improved control, reduced electromagnetic interference and greater reliability. This paper proposes the use of multilevel converters for providing induction heating power at two frequencies simultaneously. It also describes how the stepping angles for the desired output from this converter were determined. Furthermore, experimental results are presented as a verification of the analysis.

Meeting Name

29th Annual Conference of the IEEE Industrial Electronics Society, IECON '03. (2003, Roanoke, VA)


Electrical and Computer Engineering

Keywords and Phrases

Dual-Frequency Voltage Generation; Gears; Heat-Treating Workpieces; Induction Heating; Induction Heating Power Supply; Multilevel Converter-Based Power Supply; Multilevel Converters; Power Convertors; Power Supplies to Apparatus; Single-Frequency Power Supply; Uneven Geometries

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type





© 2003 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Jan 2003