Power converter comprising: - a positive converter bridge (P+) intended to be connected to the phases of a first secondary (U Δ, V Δ, W Δ) and to the phases of a second secondary (U Y, V Y, W Y) of a transformer, - - a negative converter bridge (P-) intended to be connected to the phases of the first secondary (U Δ, V Δ, W Δ) and to the phases of the second secondary (U Y, V Y, W Y) of the transformer, the positive converter bridge (P+) and the negative converter bridge (P-) being of the Graëtz bridge type and being assembled in parallel, each converter bridge (P+; P-) comprising a first series of groups of semi-conductor components (U Δ +, V Δ +, W Δ +; U Δ -, V Δ -, W Δ -) and fuses connected to the phases of the first secondary (U Δ, V Δ, W Δ) of the transformer and a second series of groups of semi-conductor components (U Y +, V Y +, W Y +; U Y -, V Y -, W Y -) and fuses connected to the phases of the second secondary of the transformer, characterised in that at least one series of groups of components (U Δ +, V Δ +, W Δ +) comprises arms (B1, B2, B3), each one formed by putting of several diodes and/or thyristors in parallel, in that at least one first portion (B1, B2) of the arms of said at least one series of groups of components (U Δ +, V Δ +, W Δ +) comprises arms aligned in a first plane (Δ1) and through which passes the first plane (Δ1), in that at least one second portion (B2, B3) of the arms of said at least one series of groups of components (U Δ +, V Δ +, W Δ +) comprises arms aligned in a second plane (Δ2) and through which passes the second plane (Δ2), the first plane (Δ1) and the second plane (Δ2) being secant on a straight line, the straight line extending perpendicularly to one (P+) at least of the positive converter bridge (P+) and of the negative converter bridge (P-) comprising said at least one series of groups of components (U Δ +, V Δ +, W Δ +), the arms (B1, B2) of said at least one first portion (B1, B2) of the arms and the arms (B2, B3) of said at least one second portion (B2, B3) of the arms extending parallel relative to one another and parallel to the straight line, the arms (B1, B2, B3) being thus arranged relative to one another such that they are nonaligned in the same plane transversal to the straight line, and in that the arms (B1, B2, B3) of said at least one series of groups of components (U Δ +, V Δ +, W Δ +) define, when observed as a cross-section, the vertices of an isosceles triangle, the maximum value (dI max) of the current imbalance in a given group of the positive converter bridge (P+) and/or of the negative converter bridge (P-) being less than or equal to 15%, this maximum value (dI max) being determined by the following formula: dImax = 100 × Imax of a component in the group − Iaverage of all the components in the group Iaverage of all the components in the group - a positive converter bridge (P+) intended to be connected to the phases of a first secondary (U Δ, V Δ, W Δ) and to the phases of a second secondary (U Y, V Y, W Y) of a transformer, - - a negative converter bridge (P-) intended to be connected to the phases of the first secondary (U Δ, V Δ, W Δ) and to the phases of the second secondary (U Y, V Y, W Y) of the transformer,