<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> The dynamics of a zero-average dynamic strategy controlled dc–dc Buck converter, modelled by a set of differential equations with discontinuous right-hand side is studied. Period-doubling and <emphasis emphasistype="italic">corner-collision</emphasis> bifurcations are found to occur close to each other under small parameter variations. Closer examination of the parameter space leads to the discovery of a novel bifurcation. This type of bifurcation has not been reported so far in the literature and it corresponds to a corner-collision bifurcation of a nonhyperbolic cycle. The bifurcation boundaries are computed analytically in this paper and the system dynamics are unfolded close to the novel bifurcation point.<footnoteref refid="fn1"/><footnote id="fn1"><footnotepara>This paper was completed during a research period of all the authors at the CRM in Barcelona in March 2007.</footnotepara> </footnote> </para>