Self-healing capacitor

A self-healing power capacitor comprising at least one capacitor unit, each capacitor unit comprising at least one winding, made of at least two films of insulating material on which a metal coating has been applied, said at least one winding of each capacitor unit being provided with a first and a second connection electrode, said at least one winding being surrounded by an encapsulation material and housed in a first casing, said capacitor having at least one protection element for each capacitor winding, said protection element being mounted in a second casing, of which one side is formed by a membrane, said protection element being provided for activating, upon a pressure exerted on said membrane by a gas produced by a short-circuit within said at least one winding, a current interruption element connected in series with one of said electrodes, said protection element being separated from an end-face of said at least one winding, characterized in that said second casing is lodged inside said first casing, separated from the top or bottom walls belonging to said first casing, said second casing being lodged in said encapsulation material and having at least one wall separated by a narrow gap from said at least one winding.