A core body includes a central iron core, an outer peripheral iron core surrounding the central iron core, and a single hoop material wound body formed by winding a hoop material. At least three iron portions of an outer circumferential surface of the hoop material wound body are bent radially inward thereof. The central iron core includes at least three iron cores, each of which having a cut tip, is made by cutting at least three projection portions of the hoop material wound body. Each of the at least three projection portions is located between the at least three portions.

A multi-phase shift transformer based AC-DC converter includes a single transformer that reflects a negative portion of an AC voltage to become a positive voltage by generating multiple phases from a poly-phase input. The multiple phases generated can be separated by as little as 1° to create a well-approximated DC output without the need for a smoothing circuit. The primary and second windings of the transformer are flat wire conductors structured to provide a larger number of windings per core including a larger number of secondary coils, which provides for a large number of output phases.

A multi-phase shift transformer based AC-DC converter includes a single transformer that reflects a negative portion of an AC voltage to become a positive voltage by generating multiple phases from a poly-phase input. The multiple phases generated can be separated by as little as 1° to create a well-approximated DC output without the need for a smoothing circuit. The primary and second windings of the transformer are flat wire conductors structured to provide a larger number of windings per core including a larger number of secondary coils, which provides for a large number of output phases.

The present disclosure relates to systems and configurations for phase-shift autotransformers and multi-pulse rectifiers. A phase-shift autotransformer includes a wiring configuration for first, second and third magnetic cores, the wiring configuration including primary input and phase-shift windings. The primary input windings are configured to provide a first and second primary input inductances, and phase-shift windings of the wiring configuration are configured to provide multiple inductances for each phase-shift winding. A multi-pulse rectifier is provided including a phase-shifting autotransformer, a diode bridge rectifier configuration coupled to output of the autotransformer and a filtering capacitor coupled to the diode bridge rectifier. Other embodiments are directed to use of the multi-use rectifier system with vehicle charging station, such as an Electric Vehicle Supply Equipment (EVSE).

The present disclosure relates to systems and configurations for phase-shift autotransformers and multi-pulse rectifiers. A phase-shift autotransformer includes a wiring configuration for first, second and third magnetic cores, the wiring configuration including primary input and phase-shift windings. The primary input windings are configured to provide a first and second primary input inductances, and phase-shift windings of the wiring configuration are configured to provide multiple inductances for each phase-shift winding. A multi-pulse rectifier is provided including a phase-shifting autotransformer, a diode bridge rectifier configuration coupled to output of the autotransformer and a filtering capacitor coupled to the diode bridge rectifier. Other embodiments are directed to use of the multi-use rectifier system with vehicle charging station, such as an Electric Vehicle Supply Equipment (EVSE).

A zero-sequence blocking transformer includes a first core part around which is wound a first winding and a second core part around which is wound a second winding, and a third core part to create an additional leakage flux path. The concept of this disclosure can be applied to any known core structure by adding an additional leakage flux component part. In the case of a known toroidal core, the additional component part may be a rod of magnetic material fitted into the gap between the two windings to intentionally create an additional leakage flux path. Alternatively, an EE core geometry can be used and the additional leakage flux path is created by forming an air gap or adding a magnetic material insert in the leg which does not carry a winding.

A unit power cell of an inverter system, according to one embodiment of the present invention, comprises: a first leg including first and fourth switching elements, which are connected in series to each other, second and third switching elements, which are connected in series with each other between a connection point of the first and second switching elements and a smoothing unit, and first, second, third and fourth diodes, which are inversely and respectively connected in parallel with the first, second, third and fourth switching elements; and a second leg connected in parallel with the first leg and including fifth and sixth switching elements, which are connected in series to each other, and fifth and sixth diodes, which are inversely and respectively connected in parallel with the fifth and sixth switching elements.

A unit power cell of an inverter system, according to one embodiment of the present invention, comprises: a first leg including first and fourth switching elements, which are connected in series to each other, second and third switching elements, which are connected in series with each other between a connection point of the first and second switching elements and a smoothing unit, and first, second, third and fourth diodes, which are inversely and respectively connected in parallel with the first, second, third and fourth switching elements; and a second leg connected in parallel with the first leg and including fifth and sixth switching elements, which are connected in series to each other, and fifth and sixth diodes, which are inversely and respectively connected in parallel with the fifth and sixth switching elements.

In some embodiments, a connection bar is provided for connecting multiple high voltage coils of a dry-type transformer along a top or bottom of the dry-type transformer. The connection bar includes (1) an electrically insulating body having a plurality of openings, each opening sized to receive at least one of high voltage terminals of the transformer; (2) an electrical connection pathway within the electrically insulating body configured to create a predetermined electrical connection between multiple high voltage coils of the transformer; (3) external connector terminals embedded within and extending from the electrically insulating body, the external connector terminals connected to the electrical connection pathway; and (4) a ground shield embedded within the electrically insulating body and configured to shield high voltage terminals of each high voltage coil of the transformer. Numerous other aspects are provided.

The present invention allows individual control of an output voltage of a main transformer and an output voltage of a teaser transformer while utilizing output characteristics of the respective transformer when a Scott connected transformer has control equipment arranged on the input side thereof, including first control equipment arranged in one of two phases of the main transformer on the input side in order to control a voltage or a current and second control equipment arranged in one end of a primary coil of the teaser transformer on the input side in order to control a voltage or a current, the control equipment controlling an output voltage of the main transformer and an output voltage of the teaser transformer individually.