Analysis and Design of Series Resonant Converter by State-Plane Diagram

Analysis based on the state-plane diagram is given for series resonant converters operating in the frequency range 0.5 ¿ fs/fo ¿ 1.0. When the voltages and currents in the converter are normalized, design parameters take on special geometric meanings in the normalized state diagram. Examples of converter design using graphical methods are given for the cases of ¿ and ¿ control. Control characteristics of the converter operating in the continuous conduction mode are derived. The concept of the energy reflection coefficient is introduced as a measure of power transfer efficiency in the converter design.