Performance prediction of DC-DC converters with impedances as loads

This paper presents a method of predicting the outer loop gain of dc-dc converters when there is a general (nonresistive) impedance as a load. Based on this prediction, it is possible to then derive a corresponding phase margin, gain margin and bandwidth in order to define a dc-dc converter's stable operating area. Two applications of the method are presented for performance prediction in: 1) dc-dc converters with additional capacitors placed across their load; 2) source converters in a distributed power system. In both applications, the theoretical predictions match closely to the experimental data.