Control unit of a switching converter operating in continuous-conduction and peak-current-control mode

摘要

A control unit for a switching converter has an inductor element coupled to an input and a switch element coupled to the inductor element and generates a command signal having a switching period to switch the switch element and determine a first time period in which an inductor current is flowing in the inductor element for storing energy and a second time period in which energy is transferred to a load. An input current is distorted relative to a sinusoid by a distortion factor caused by current ripple on the inductor current. The duration of the first time period is determined based on a comparison between a peak value of the inductor current and a current reference that is a function of an output voltage of said voltage converter. A reference modification stage modifies one of the current reference and sensed value of the inductor current to compensate for distortion introduced by the distortion factor on the input current.