Fourth-Order SEPIC Converter Order Diminution and Interval Modeling

The single-ended primary-inductor converter(SEPIC) is a DC-to-DC converter that allows both the operations of voltage level steps up and steps down. The SEPIC converter output is controlled by the switch duty cycle. The SEPIC converter consists of two inductors and two capacitors; hence it is a fourth-order converter. The state space model is obtained by using the state space averaging technique. Further, its order is reduced to first, second and third order using a modified Routh table and stability equation-based diminution techniques. Impulse response, step response, and Bode response of both the interval limits are plotted. The results show the usability and effectiveness of the proposed converter.