A method for manufacturing a heavy-current transformer with at least one primary winding and at least one secondary winding with surfaces for contacting connects first inner surfaces of the at least one secondary winding with an I-beam of electrically conductive material of the heavy-current transformer with a first soldering material at a first, higher melting temperature, and subsequently at least one contact plate of electrically conductive material is soldered with exterior surfaces of the at least one secondary winding with a second soldering material at a second melting temperature that is lower as compared to the first melting temperature.

A method for manufacturing a heavy-current transformer with at least one primary winding and at least one secondary winding with surfaces for contacting connects first inner surfaces of the at least one secondary winding with an I-beam of electrically conductive material of the heavy-current transformer with a first soldering material at a first, higher melting temperature, and subsequently at least one contact plate of electrically conductive material is soldered with exterior surfaces of the at least one secondary winding with a second soldering material at a second melting temperature that is lower as compared to the first melting temperature.

A choke coil module of a high power density DC-AC power inverter includes a retainer. The retainer includes a lower plate and an upper plate. The upper and lower plates are spaced from each other and have two slots, respectively. An accommodation space of the retainer is provided with two choke coils which are disposed obliquely in a stagger manner. Top portions and bottom portions of the choke coils protrude out of and lean against the slots of the upper plate and the lower plate, respectively. The outside air is guided by a fan unit to enter a casing through air inlets, and the heat generated by the choke coils is expelled to the outside through air outlets. The choke coil module can be mounted in a smaller casing, such as a casing with a height of 2 U, to achieve excellent heat dissipation.

A choke coil module of a high power density DC-AC power inverter includes a retainer. The retainer includes a lower plate and an upper plate. The upper and lower plates are spaced from each other and have two slots, respectively. An accommodation space of the retainer is provided with two choke coils which are disposed obliquely in a stagger manner. Top portions and bottom portions of the choke coils protrude out of and lean against the slots of the upper plate and the lower plate, respectively. The outside air is guided by a fan unit to enter a casing through air inlets, and the heat generated by the choke coils is expelled to the outside through air outlets. The choke coil module can be mounted in a smaller casing, such as a casing with a height of 2 U, to achieve excellent heat dissipation.

A toroidal magnetic element. A plurality of coils is arranged in a toroidal configuration. Each coil may be a hollow cylinder, formed by winding a rectangular wire into a roll. The coils alternate with spacers, each of which may be a wedge. The coils may alternate in winding orientation, and the inner end of each coil may be connected, through an S-Bend to the inner end of an adjacent coil. Small gaps are formed between the coils and the wedges, e.g. as a result of each wedge having, on its two faces, a plurality of raised ribs, against which the coils abut. Cooling fluid flows through the gaps to cool the coils.

A toroidal magnetic element. A plurality of coils is arranged in a toroidal configuration. Each coil may be a hollow cylinder, formed by winding a rectangular wire into a roll. The coils alternate with spacers, each of which may be a wedge. The coils may alternate in winding orientation, and the inner end of each coil may be connected, through an S-Bend to the inner end of an adjacent coil. Small gaps are formed between the coils and the wedges, e.g. as a result of each wedge having, on its two faces, a plurality of raised ribs, against which the coils abut. Cooling fluid flows through the gaps to cool the coils.

A radio frequency (RF) matching system may include an airflow generator configured to generate an airflow stream and an induction coil apparatus positioned within the airflow stream to be generated by the airflow generator. The induction coil apparatus may include an induction coil and an airflow guide positioned and configured to direct the airflow stream to be generated by the airflow generator over the induction coil. The airflow generator may be downstream or upstream of the induction coil apparatus in the airflow stream to be generated by the airflow generator.

A radio frequency (RF) matching system may include an airflow generator configured to generate an airflow stream and an induction coil apparatus positioned within the airflow stream to be generated by the airflow generator. The induction coil apparatus may include an induction coil and an airflow guide positioned and configured to direct the airflow stream to be generated by the airflow generator over the induction coil. The airflow generator may be downstream or upstream of the induction coil apparatus in the airflow stream to be generated by the airflow generator.

A cooling structure for a transformer according to an embodiment includes a coil and a partition member. The partition member covers the coil along the axial direction on the downstream side in the flow direction of the refrigerant that flows along the axial direction parallel to the center axis of the coil.

A cooling structure for a transformer according to an embodiment includes a coil and a partition member. The partition member covers the coil along the axial direction on the downstream side in the flow direction of the refrigerant that flows along the axial direction parallel to the center axis of the coil.