Abstract: A method for operating a single-phase, mid-frequency welding transformer formed with a transformer core having a primary coil and a secondary coil connected into a secondary circuit has several steps. The several steps include regulating a magnetic flux density (B) in the transformer core between an upper flux density threshold value (Bm) and a lower flux density threshold value (?Bm), by applying, in alteration, a first voltage (UDC) and a second voltage (?UDC) to the primary coil of the transformer, and regulating a load current (ibr) in the secondary circuit between an upper load current threshold value (ibr-zg) and a lower load current threshold value (ibr-sp), by applying, in alternation, a third voltage (0V)to the primary coil of the transformer.

Abstract: The invention relates to a winding element (200) for conducting current, forming a component of a coil winding (132, 133; 408, 409), especially of a (welding) transformer winding, comprising fixing means (205) for fixing the winding element (200) to a carrier component (402, 403, 404). The invention also relates to a transformer arrangement (100; 600), especially a welding transformer arrangement, comprising a primary winding (132; 408) and a secondary winding (133; 409), the primary winding (132; 408) and/or secondary winding (133; 409) comprising at least one winding element (200) according to the invention.

Abstract: A semiconductor module (500) for connecting to a transformer winding (132, 133; 408; 409) includes a semiconductor component (501) that is disk-shaped and disposed between two contact plates (502). One of the contact plates (502) is acted upon using a cooling fluid on its side facing away from the semiconductor component (501).

Abstract: The invention relates to a semiconductor module (500) for connecting to a transformer winding (132, 133; 408, 409), especially a welding transformer winding. An especially disk-shaped semiconductor component (501) is arranged between two contact plates (502), and a cooling fluid can be applied to the side of at least one contact plate (502), which opposes the semiconductor component (501). The invention also relates to a transformer arrangement (100; 600), especially a welding transformer arrangement, comprising a primary winding (132; 408) and a secondary winding (133; 409) with a downstream output rectifier arrangement (604). The output rectifier arrangement (604) comprises at least one semiconductor module embodied as a rectifier assembly (500) and provided with a rectifier diode (501).

Abstract: The invention relates to a winding element (200) for conducting current, forming a component of a coil winding (132, 133; 408, 409), especially of a (welding) transformer winding, comprising fixing means (205) for fixing the winding element (200) to a carrier component (402, 403, 404). The invention also relates to a transformer arrangement (100; 600), especially a welding transformer arrangement, comprising a primary winding (132; 408) and a secondary winding (133; 409), the primary winding (132; 408) and/or secondary winding (133; 409) comprising at least one winding element (200) according to the invention.

Abstract: The invention relates to a method for operating a transformer (130), in particular a (single-phase) mid-frequency welding transformer, with a transformer core (131) with a primary winding (132) and a secondary winding (133), which is connected into a secondary circuit (120), comprising the regulation of a magnetic flux density (B) in the transformer core (131) between an upper flux density threshold value (Bm) and a lower flux density threshold value (?Bm) and the regulation of a load current (ibr) in the secondary circuit (120) between an upper load current threshold value (ibr-zg) and a lower load current threshold value (ibr-sp). The invention likewise relates to a corresponding apparatus (200). The invention reduces in particular voltage peaks and saturation effects, which otherwise occur during operation of a mid-frequency transformer.