  Current-mode control is one of the most popular controller strategies for
power converters. With the advent of wide bandgap devices including GaN and
SiC, higher switching frequencies have become more viable at higher power
because of lower switching losses. However, the advantage of higher switching
frequency for faster, higher bandwidth control is squandered because of current
sensor interference. We present a framework for characterizing and analyzing
this interference as uncertainties to the controller model. These uncertainties
introduce additional dynamics and nonlinearity that can result in instability
and poor transient performance of the current control loop. In this paper, we
provide a model framework based on a new control conditioning approach that
guarantees global stability and a strategy for optimizing transient
performance. In Part II of this paper series, we present the analysis, design,
and hardware validation of three effective solutions.
