A sealed core-coil assembly in a submersible transformer includes a coil assembly having an inner coil with inner, outer, upper, and lower surfaces, and an outer coil with inner, outer, upper, and lower surfaces, a core assembly including a core window and core column of a magnetically-permeable material, the core column and core window having inner side surfaces, and an expandable sealing member including an inner cavity that is fillable or evacuatable so that a compliant insulation material is positioned in the inner cavity to block passage of water and prevent the formation of a loop of water, which otherwise would act like an electrical short in a submerged transformer.

A three-phase power supply circuit is provided. The power supply circuit includes three LLC resonant voltage convertors, three step-down transformers, and a bridge rectifier. Each step-down transformer includes a primary and secondary coil, and each primary and secondary coil has a first node and a second node. Each step-down transformer is electrically coupled with one of the three LLC resonant voltage convertors by the first and second nodes of the primary coils. The bridge rectifier is electrically coupled with the first node of the secondary coil of each of the three step-down transformers. The second nodes of the secondary coils of each of the three step-down transformers are electrically coupled together.

A three-phase autotransformer including three output groups and three inputs each connected to each of the outputs of a respective output group by windings, the windings being configured so that, when each input has a respective input voltage applied thereto, the three input voltages having the same input amplitude, being 120° out of phase with each other and defining a neutral point: for each output group, a main output voltage, taken between a main output of said output group and the neutral point, has an amplitude greater than the input amplitude; and output voltages of the autotransformer belong to a same Reuleaux polygon, each output voltage being associated with a respective output and being equal to a voltage between said output and the neutral point.

A three-phase autotransformer including three output groups and three inputs each connected to each of the outputs of a respective output group by windings, the windings being configured so that, when each input has a respective input voltage applied thereto, the three input voltages having the same input amplitude, being 120° out of phase with each other and defining a neutral point: for each output group, a main output voltage, taken between a main output of said output group and the neutral point, has an amplitude greater than the input amplitude; and output voltages of the autotransformer belong to a same Reuleaux polygon, each output voltage being associated with a respective output and being equal to a voltage between said output and the neutral point.

A magnetic component includes two ferromagnetic half-cores stacked and superposed to form a ferromagnetic core comprising three legs, namely two first legs and one second leg. Each leg is formed from two facing half-legs separated by a gap, and each leg incudes a primary winding and a secondary winding having a winding direction, on each of the half-legs forming the leg, respectively. The magnetic component is characterized in that, on the second leg, the primary winding and the secondary winding and their winding directions are inverted with respect to those of the first legs.

A design method of a transformer repeats following steps until a preset condition is met: calculating an output voltage of each secondary winding according to a phase shift angle and a number of turns of the each secondary winding; obtaining a difference between output voltages of each secondary winding pair in a secondary winding set; adjusting the phase shift angle of at least one secondary winding in the secondary winding set; and obtaining a final number of turns for the each secondary winding according to a resultant phase shift angle corresponding to when the preset condition is met; where the preset condition is that the difference between the output voltages of any secondary winding pair in the secondary winding set is less than or equal to a preset threshold.

A transformer device includes: a transformer including a core and a coil a suspension tool attachment unit disposed above the coil and connected to the core and a cover body having an internal space and connected to the suspension tool attachment unit (32). A suspension tool for suspending the transformer device including the transformer and the cover is attachable to the suspension tool attachment unit The cover body is provided with: a first opening located below a first phase transformer and allowing communication between the internal space and a space outside the internal space a second opening located above a third phase transformer and allowing communication between the internal space and the space outside the internal space An air flow is formed such that air flows into the internal space through the first opening and is discharged to the space outside the internal space through the second opening

A transformer device includes: a transformer including a core and a coil a suspension tool attachment unit disposed above the coil and connected to the core and a cover body having an internal space and connected to the suspension tool attachment unit (32). A suspension tool for suspending the transformer device including the transformer and the cover is attachable to the suspension tool attachment unit The cover body is provided with: a first opening located below a first phase transformer and allowing communication between the internal space and a space outside the internal space a second opening located above a third phase transformer and allowing communication between the internal space and the space outside the internal space An air flow is formed such that air flows into the internal space through the first opening and is discharged to the space outside the internal space through the second opening

The present invention relates to a method of operating an ozone generator, a transformer assembly and an ozone generator apparatus configured to be operated at an operational frequency range between 25-40 kHz, such as between 30 and 40 kHz.

An integrated common mode and differential mode inductor can include a first core including a first center leg, a second core including a second center leg, a first center winding on the first center leg, and a second center winding on the second center leg. The first center leg can be spaced apart from the second center leg, for example by a center air gap. The integrated common mode and differential mode inductor can further include a left winding on a first left leg of the first core and a second left leg of the second core, as well as a right winding on a first right leg of the first core and a second right leg of the second core.