A transformer includes a closed loop core having a first leg and a second leg. The transformer also includes a first primary winding surrounding the first and second legs, a second primary winding surrounding the first and second legs, and first and second secondary windings surrounding the first and second legs, respectively, and disposed between the first and second primary windings. A first turn of the first and second secondary windings are disposed on a first interlayer winding layer, and other turns of the first and second secondary windings are disposed on a first layer that is further from the first primary winding than the first interlayer winding layer.

An assembly for connecting to a high-voltage grid includes a plurality of single-phase transformers, each of which has a transformer tank that is filled with a fluid and is equipped with a core with at least one coil. The coils of the single-phase transformers are at least partly connected together, thereby forming a neutral or star point. In order to permit the assembly to be quickly assembled in situ while at the same time providing a reliable current path for compensation and grounding currents, the coils are connected together by a neutral or star point conductor or rail in order to form the neutral or star point. The neutral or star point conductor or rail is retained in an insulated manner on the transformer tank.

An assembly for connecting to a high-voltage grid includes a plurality of single-phase transformers, each of which has a transformer tank that is filled with a fluid and is equipped with a core with at least one coil. The coils of the single-phase transformers are at least partly connected together, thereby forming a neutral or star point. In order to permit the assembly to be quickly assembled in situ while at the same time providing a reliable current path for compensation and grounding currents, the coils are connected together by a neutral or star point conductor or rail in order to form the neutral or star point. The neutral or star point conductor or rail is retained in an insulated manner on the transformer tank.

A power converter performs DC power conversion between a pair of first DC terminals and a pair of second DC terminals. DC nodes of n DC/AC converters are connected in parallel or in series between the first DC terminals. A multiple transformer has n primary windings and n secondary windings. An AC node of each DC/AC converter is connected to its corresponding primary winding. An AC node of each AC/DC converter is connected to its corresponding secondary winding. DC nodes of n AC/DC converters are connected in series or in parallel between the second DC terminals. The multiple transformer is configured such that a magnetic path is shared among the n primary windings and a magnetic path is shared among the n secondary windings.

A power converter performs DC power conversion between a pair of first DC terminals and a pair of second DC terminals. DC nodes of n DC/AC converters are connected in parallel or in series between the first DC terminals. A multiple transformer has n primary windings and n secondary windings. An AC node of each DC/AC converter is connected to its corresponding primary winding. An AC node of each AC/DC converter is connected to its corresponding secondary winding. DC nodes of n AC/DC converters are connected in series or in parallel between the second DC terminals. The multiple transformer is configured such that a magnetic path is shared among the n primary windings and a magnetic path is shared among the n secondary windings.

A power conversion device includes an isolation transformer, the isolation transformer including: a primary winding; a secondary winding; and a magnetic shield portion configured to suppress magnetic interference between the primary winding and the secondary winding by interrupting a magnetic flux generated by a current flowing through each of the primary winding and the secondary winding. The magnetic shield portion is formed of, for example, a magnetic shield plate arranged between the primary winding and the secondary winding.

An assembly for connection to a high-voltage system has multiple single-phase transformers each having a transformer tank which is filled with a fluid and in which a core with at least one winding is situated. At least some of the windings of the single-phase transformers are connected to one another, forming a neutral point. A short-circuit voltage curve or impedance of the assembly can be adapted to different requirements. The windings are each connected to the neutral point via a switchover unit and a choke winding. The choke winding has multiple tappings, and the switchover unit is configured to select the tapping via which the winding in question is connected to the neutral point.

An assembly for connection to a high-voltage system has multiple single-phase transformers each having a transformer tank which is filled with a fluid and in which a core with at least one winding is situated. At least some of the windings of the single-phase transformers are connected to one another, forming a neutral point. A short-circuit voltage curve or impedance of the assembly can be adapted to different requirements. The windings are each connected to the neutral point via a switchover unit and a choke winding. The choke winding has multiple tappings, and the switchover unit is configured to select the tapping via which the winding in question is connected to the neutral point.

The invention relates to a combined transformer for an LLC resonant converter. The combined transformer includes a primary transformer winding configured to generate during operation a first magnetic flux, which forms a first magnetic circuit. The combined transformer also includes a resonant inductor having a winding, wherein the resonant inductor is configured to generate during operation a second magnetic flux, which forms a second magnetic circuit. The primary transformer winding and the winding of the resonant inductor are arranged with respect to one another such that at least one first part of the first magnetic circuit and at least one second part of the second magnetic circuit run on a magnetic path common to the first part and to the second part. The invention also relates to an LLC resonant converter with such a combined transformer.

The invention relates to a combined transformer for an LLC resonant converter. The combined transformer includes a primary transformer winding configured to generate during operation a first magnetic flux, which forms a first magnetic circuit. The combined transformer also includes a resonant inductor having a winding, wherein the resonant inductor is configured to generate during operation a second magnetic flux, which forms a second magnetic circuit. The primary transformer winding and the winding of the resonant inductor are arranged with respect to one another such that at least one first part of the first magnetic circuit and at least one second part of the second magnetic circuit run on a magnetic path common to the first part and to the second part. The invention also relates to an LLC resonant converter with such a combined transformer.