Method for operating a dc-dc converter, control apparatus for a dc-dc converter, and dc-dc converter

A method of operating a DC-DC voltage converter, the DC-DC voltage converter having a regulator unit for adjusting an output variable at an output to a prescribed setpoint value, the method comprising:

• depending on an actual value of the output variable, setting with the regulator unit a duty cycle of a pulse-width modulation of a switching signal for at least one switching transistor of the DC-DC voltage converter according to a predetermined control specification, the regulator unit having at least one operating parameter for providing the pulse-width modulation, and the operating parameter being prescribed to the regulator unit independently of the actual value, and the at least one operating parameter being a variable operating parameter;
• changing the at least one operating parameter to a respective new parameter value by way of a control apparatus, and subsequently verifying the new parameter value to determine whether, with the setpoint value unchanged and the respective new parameter value, the regulator unit sets a lower duty cycle for adjusting the output variable than before a setting of the respective new parameter value;
• if the regulator unit sets the lower duty cycle, retaining the respective new parameter value or, if the regulator unit does not set a lower duty cycle, changing back the parameter value;
• and
• wherein, as the at least one operating parameter, a period of the pulse-width modulation and/or an edge steepness of switching edges is varied by way of the respective new parameter value.