A power converter, a boost off time adaptive adjustment unit and a boost cycle short circuit protection module for controlling an off time of a boost cycle of the power converter. The boost off time adaptive adjustment unit is adapted to generate an off time control signal based at least on an input voltage and an output voltage of the power converter to regulate the off time of the boost cycle to change in an opposite direction to the output voltage when the power converter is operating normally during the boost cycle, and to regulate the off time of the boost cycle to change in a same direction as the output voltage when a short-circuit fault occurs during the power converter operating in the boost cycle.