Adaptive Voltage Positioning Design of Single Stage 48/1V Sigma Converter for Fast Transient Response
Xin Lou, Qiang Li, Mohamed H. Ahmed
Abstract
48V voltage regulator modules (VRMs) are critical for telecom power supplies and are becoming popular for future data centers. By using a novel sigma converter topology, an outstanding performance in terms of efficiency (95%) and power density (700 W/in <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> ) have been demonstrated. However, the control of the Sigma converter is challenging due to the quasi-parallel structure and has not been solved properly yet. In this paper, a control method combining V <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> control and active droop control is adopted for the Sigma converter. A design guideline is proposed to achieve adaptive voltage positioning (AVP). Following the proposed design guideline, simulation and experimental results demonstrate good transient responses.