Embodiments of the present disclosure disclose a power converter and a related system. The power converter includes a controller and a power conversion circuit. The power conversion circuit is configured to convert an input power of an input power supply into an output power of a load, where the input power supply is an external power supply connected to the power converter. The controller is configured to control on/off of the first switch element, to implement connection/disconnection between the input power supply and the inductive element; and control the unidirectional conduction circuit to be turned on before the first switch element is turned on in the power conversion cycle.