  We propose a framework that allows us to analyze different variants of HDG
methods for the static Maxwell equations using one simple analysis. It reduces
all the work to the construction of projections that best fit the structures of
the approximation spaces. As applications, we analyze four variants of HDG
methods (denoted by B, H, B+, H+), where two of them are known (variants H, B+)
and the other two are new (variants H+, B). Under certain regularity
assumption, we show that all the four variants are optimally convergent and
that variants B+ and H+ achieve superconvergence without post-processing. For
the two known variants, we prove their optimal convergence under weaker
requirements of the meshes and the stabilization functions thanks to the new
analysis techniques being introduced. For solution with low-regularity, we give
an analysis to these methods and investigate the effect of different
stabilization functions on the convergence. At the end, we provide numerical
experiments to support the analysis.
