Time-domain simulation of power electronics circuits using state variable quadratic extrapolations

A new stepwise time-domain analysis technique for power electronics circuits is presented. At each simulation step the rate of change of each state variable is determined by the corresponding reactive element parasitic resistance and state value obtained after performing a modified nodal analysis (MNA). A quadratic state trajectory description for each reactive element is formulated. To ensure the correct topological operation of the power stage, the algorithm monitors the position and checks the validity of all switches, requiring no a priori knowledge of their switching relationships. All computations require simple algebraic manipulations of resistive networks only. An example of simulating the responses of a zero-voltage-transition PWM buck converter is illustrated. The results are favorably compared to the previous method using constant nodal voltage approximation, experimental measurements, and the commercial software - PSpice.