Nonlinear Control for DC-DC Converters Based on Hysteresis of the COUT Current With a Frequency Loop to Operate at Constant Frequency. - Santa Concepción Huerta; Pedro Alou; Jesús Ángel Oliver; Óscar García; José A. Cobos; Ahmed M. Abou-Alfotouh (IEEE Trans. Ind. Electron., 2011)