Exact orbital stability analysis of static and dynamic ramp compensations in DC-DC converters

Exact orbital stability of static linear, static quadratic, and dynamic ramp compensations in current mode control for DC-DC converters is considered. On static linear ramp compensation, a well-known stability criterion is re-examined. This stability criterion, based on inductor current dynamics, is shown to be an approximate and necessary (but not sufficient) condition for system stability. A new approach based on sampled-data modeling is proposed to determine the right ramp slope to stabilize the system. On static quadratic and dynamic ramp compensations, new stabilization schemes are proposed, without changing the nominal steady-state condition.