abstract
- IEEEThis paper addresses a fundamental issue in power converter control. Namely, the direct output-voltage control of power converters with higher-order dynamics. We argue that despite of the burst in the development of new topologies, legacy control design principles ---inherited from second-order converter analysis--- have been unduly adopted as de facto rules of procedure. In particular, we refer to the minimum-phase requirement on the feedback variable, as the underlying stabilizing mechanism. In this paper, we demonstrate that the requirement of minimum-phaseness for higher-order converters and the legacy ad hoc solution via ancillary current-control, can be bypassed without compromising closed-loop performance. To prove this, we unveil important differences between stability properties of second-order and higher-order converters. Then, we introduce new linear and nonlinear control design strategies that permit direct output-voltage control. Experimental results are provided to validate the theory.