H. Ertl, J.W. Kolar, F. Zach:
"Analysis of a Multi-Level Multi-Cell Switch-Mode Power Amplifier";
Poster: International Conference on Power Conversion and Intelligent Motion (PCIM), Nürnberg, Deutschland; 06-06-2000 - 06-08-2000; in: "Proceedings", Proceedings of the 41th International Conference o (2000), 491 - 497.

The paper presents a novel switch-mode power amplifier based on a multi-cell multi-level circuit topology. The total output voltage of the system is formed by series connection of several switching cells having a low DC link voltage which, therefore, can be equipped by modern low-voltage high-current power MOS-FET devices. The cells are operated in a phase-shifted PWM mode which in connection with the low partial voltage of each cell dramatically reduces the filtering effort at the output of the total amplifier and conse-quently improves the dynamic system behavior. The paper describes the operating principle of the system, analyzes the funda-men-tal relation-ships being relevant for the circuit design and gives guidelines for the dimensioning of the con-trol circuit. Furthermore, simu-lation results as well as results of measurements taken from a laboratory prototype circuit are presented.