This application provides a new power conversion apparatus and a method for driving the power conversion apparatus. In the power conversion apparatus provided in this application, two switching transistors in a bridge arm circuit of an input converter are separately connected in parallel to a circuit formed by connecting a switching transistor and a capacitor in series, and/or two switching transistors in a bridge arm circuit of an output converter are separately connected in parallel to a circuit formed by connecting a switching transistor and a capacitor in series. The power conversion apparatus provided in this application has a larger gain range of an output voltage when driven by a corresponding driving method.