ANALYSIS OF COMMON SWITCHING CONVERTERS USING Z-TRANSFORM

A method for switching converters analysis, using the Z-transform is presented. The method uses state-space formulation to analyze the converter transient and steady-state behavior in each cycle, whereby the initial conditions of state variables in each cycle are treated as discrete quantities. The difference equation for such quantities is solved in ''closed'' analytical form, using the Z-transform. The mehtod is illustrated by the application of a three-storage-element two-configuration DC-to-AC resonant inverter. The resonant curve of such an inverter is obtained and shows that the resonance can occur on different switching frequencies.