Transformer and power converter

2:

• The transformer according to claim 1, wherein
• each of the plurality of winding portions includes a pair of low-voltage windings as the first winding and a high-voltage winding as the second winding sandwiched between the pair of low-voltage windings, and
• the high-voltage winding is spaced from each of the pair of low-voltage windings,
• an insulation distance is maintained between each of the pair of low-voltage windings and a corresponding one of the iron core stacks, the insulation distance corresponding to a difference between a potential generated in each of the pair of low-voltage windings and a potential present in the corresponding one of the iron core stacks,
• an insulation distance is maintained between the high-voltage winding and each of the iron core stacks, the insulation distance corresponding to a difference between a potential generated in the high-voltage winding and each of the iron core stacks, and
• an appropriate insulation distance is maintained between each of the pair of low-voltage windings and the high-voltage winding, the appropriate insulation distance corresponding to a difference between a potential generated in each of the pair of low-voltage windings and a potential generated in the high-voltage winding.

5:

• The transformer according to claim 1, further comprising:
• a tank to accommodate the first iron core group, the second iron core group, and the plurality of winding portions;
• and
• insulating oil filling the tank,
• wherein the first iron core group, the second iron core group, and the plurality of winding portions are immersed in the insulating oil within the tank.

11:

• The transformer according to claim 1, wherein
• each of the plurality of annular iron cores includes a plurality of ribbon-shaped bodies,
• the plurality of ribbon-shaped bodies include a non-magnetic material and are stacked on each other, and
• first ends and second ends of the plurality of ribbon-shaped bodies are joined to each other to form a lap portion.

16:

• A power converter comprising:
• a transformer according to claim 1;
• a first terminal to output a DC voltage;
• a second terminal to output a DC voltage;
• a plurality of DC/AC converters;
• and
• a plurality of AC/DC converters, wherein
• the plurality of DC/AC converters each have a DC terminal, a plurality of the DC terminals of the plurality of DC/AC converters being connected in parallel and connected in parallel with the first terminal,
• the plurality of AC/DC converters each have a DC terminal, a plurality of the DC terminals of the plurality of AC/DC converters being connected in series and connected in parallel with the second terminal,
• the DC/AC converters each have an AC terminal, a plurality of the AC terminals of the DC/AC converters being connected to a low-voltage AC terminal of the transformer, and
• the AC/DC converters each have an AC terminal, a plurality of the AC terminals of the AC/DC converters being connected to a high-voltage AC terminal of the transformer.

18:

• The power converter according to claim 17, wherein
• each of the DC/AC converters and the AC/DC converters includes
• a bridge circuit formed of a DC capacitor connected in parallel with the DC terminal, and
• two switching legs including the semiconductor switching elements connected in series, and
• each of the semiconductor switching elements is connected in parallel with a snubber capacitor.

20:

• A transformer comprising:
• a first iron core group including a plurality of iron core stacks adjacent to each other;
• a second iron core group disposed to face the first iron core group while being spaced therefrom, the second iron core group including a plurality of iron core stacks each disposed to face a corresponding one of the plurality of iron core stacks of the first iron core group;
• and
• a plurality of winding portions each wound across a corresponding one of the plurality of iron core stacks of the first iron core group and a corresponding one of the plurality of iron core stacks of the second iron core group, the corresponding one of the plurality of iron core stacks of the second iron core group facing the corresponding one of the plurality of iron core stacks of the first iron core group, wherein
• the plurality of iron core stacks of the first iron core group and the plurality of iron core stacks of the second iron core group each include a plurality of annular iron cores stacked on each other,
• the plurality of iron core stacks of the first iron core group are disposed side by side in a first direction, and the plurality of iron core stacks of the second iron core group are disposed side by side in the first direction in parallel with the first iron core group,
• the plurality of iron core stacks of the first iron core group and the plurality of iron core stacks of the second iron core group each have an iron core window passing through in a second direction intersecting the first direction,
• each of the plurality of winding portions is wound, through the iron core window of a corresponding of the plurality of iron core stacks, across a corresponding one of the plurality of iron core stacks of the first iron core group and a corresponding one of the plurality of iron core stacks of the second iron core group, the corresponding one of the plurality of iron core stacks of the first iron core group and the corresponding one of the plurality of iron core stacks of the second iron core group facing each other in a third direction intersecting the first direction and the second direction,
• the plurality of iron core stacks are provided in the first direction to be in direct contact with each other or in indirect contact each other with an insulation including a non-magnetic material.