An efficient technique for the time-domain simulation of power electronic circuits

A general-oriented time-domain simulation algorithm for power electronic circuits is presented. The methodology is based on stepwise quadratic formulation of circuit state variable trajectory with progressive analysis of switches´ operation. At each simulation step, the circuit topology is transformed into a purely resistive network which is analyzed by the modified nodal analysis (MNA) technique. The rate of change of each state variable is determined by its parasitic resistance and instantaneous value. The trajectory of each state variable and switch branch voltage is expressed by a quadratic description. A simple and efficient method is used to determine the switching instants of circuit topologies. The prominent features of this approach include: (1) its simplicity in solving resistive network only throughout the analysis without dealing with any complicated Laplace-transformed equation or differential formula; (2) its generality in determining valid circuit topology without prior understanding of the switching relationships; (3) its directness in calculating the switching instants; and (4) its inherent consideration of the parasitic resistance of each reactive element in the analysis. Two examples illustrating the generality and computational efficiency of the proposed algorithm are presented. The simulated results are favorably compared to the method used in available literature and the commercial software, PSpice