Power converter (1) with: a switching circuit (20); a
capacitor module (3) which is electrically connected to the switching circuit; an auxiliary
capacitor module (5) connected in parallel to the
capacitor module; and a device housing (12) which contains the switching circuit, the capacitor module and the auxiliary capacitor module, wherein The capacitor module includes: a capacitor element (31), a capacitor housing (32) that contains the capacitor element, an encapsulation resin (33) that encapsulates the capacitor element in the capacitor housing, and a capacitor
busbar (4) which connects the capacitor element to a power terminal of the switching circuit, wherein the capacitor
busbar includes: an element connection section (41) that is connected to the capacitor element within the encapsulation resin, a connecting section (42) which is connected to the power connection outside the encapsulation resin, and a power supply connection section (43) which is connected to a power supply wiring (54) outside the encapsulation resin, wherein the power supply wiring is electrically connected to a DC power supply, wherein the capacitor
busbar includes a DC path (44) which represents a current path between the terminal connection section and the power supply connection section, and the DC path is exposed to the outside of the encapsulation resin, the auxiliary capacitor module is connected to the power supply connection section of the capacitor busbar, the auxiliary capacitor module is detachably attached to the power supply connection section by means of a fastening element (11), and a fastening direction of a fastening element (135) that secures the auxiliary capacitor module and a fastening direction of the fixing element are the same.