Pulse transformer for firing thyristors

Claim 2

A pulse transformer for firing thyristors comprising a primary conductor conductively connected to a pulse generator, an insulating cylinder through which the primary conductor extends, and a plurality of transformer units fitted around said primary conductor through said insulating cylinder therebetween, each of said transformer units including a magnetic iron core, a secondary winding wound on said iron core and connected to the gate of a thyristor and an insulating body for insulating said secondary winding, a first conductive layer disposed in the inner peripheral portion of the insulating cylinder and kept at the same potential as the primary conductor; second conductive layers disposed in the inner peripheral portions of said insulating bodies of at least those transformer units which are positioned on the higher voltage side, facing said insulating cylinder; third conductive layers disposed in those surface portions of said insulating cylinder which face said second conductive layers, said second conductive layers being electrically connected to said third conductive layers, respectively.

Claim 3

A pulse transformer for firing thyristors as defined in claim 1, wherein each of said second conductive layers is formed in the inner peripheral portion and in the upper and lower surface portions of said insulating body.

Claim 4

A pulse transformer for firing thyristors as defined in claim 1, wherein said second conductive layers are embedded in said insulating bodies.

Claim 5

A pulse transformer for firing thyristors as defined in claim 1, wherein each of said third conductive layers extends beyond the upper and lower surface of the corresponding transformer unit.

Claim 6

A pulse transformer for firing thyristors as defined in claim 1, wherein said third conductive layers are disposed adjacent the surface of said insulating cylinder.

Claim 7

A pulse transformer for firing thyristors as defined in claim 1, wherein said primary conductor is formed in a hollow cylindrical shape with a cable penetrating through said hollow portion.

Claim 8

A pulse transformer for firing thyristors as defined in claim 1, wherein each of said transformer units includes a plurality of electrically separated secondary windings disposed on an annular magnetic iron core with equal spacings, and terminals corresponding to the respective Secondary windings and projected from said insulating body.

Claim 9

A pulse transformer for firing thyristors as defined in claim 1, further comprising a mounting base, a support seat mounted on said mounting base, an upper and a lower vessel attached to the upper and the lower end portion of said insulating cylinder, resilient means for resiliently supporting said upper vessel on said support seat, and guide means for guiding said vessel at a position in said mounting base.

Claim 10

A pulse transformer for firing thyristors comprising a primary conductor conductively connected to a pulse generator, an insulating cylinder through which said primary conductor penetrates, and plurality of transformer units fitted around said primary conductor with said insulating cylinder disposed therebetween, each of said transformer units including a magnetic iron core, a secondary winding wound around said iron core and connected to the gate of a thyristor and an insulating body for insulating said secondary winding, a plurality of mutually independent first conductive layers each disposed in those surface portions of said insulating cylinder which face a respective transformer unit, said first conductive layers being spaced with a gap in the axial direction of said insulating cylinder; and a plurality of second conductive layers embedded in said insulating cylinder in groups corresponding to and electrostatically coupling with each of said first conductive layers, said second conductive layers being offset with respect to each other in both the radial and axial directions, one end portion of said second conductive layers being positioned in radial alignment with spaced points in the gaps between said first conductive layers and being spaced and staggered from each other with a predetermined interval in the axial direction of said insulating cylinder.

Claim 11

A pulse transformer for firing thyristors comprising a primary conductor conductively connected to a pulse generator, an insulating cylinder through which said primary conductor penetrates, and plurality of transformer units fitted around said primary conductor with said insulating cylinder disposed therebetween, each of said transformer units including a magnetic iron core, a secondary winding wound around said iron core and connected to the gate of a thyristor and an insulating body for insulating said secondary winding, a plurality of mutually independent first conductive layers each disposed in those surface portions of said insulating cylinder which face a respective transformer unit, said first conductive layers being spaced with a gap in the axial direction of said insulating cylinder; and a plurality of second conductive layers embedded in said insulating cylinder in groups corresponding to and electrostatically coupling with each of said first conductive layers, said second conductive layers being offset with respect to each other in both the radial and axial directions, one end portion of said second conductive layers being positioned in radial alignment with spaced points in the gaps between said first conductive layers and being spaced and staggered from each other with a predetermined interval in the axial direction of said insulating cylinder.

Claim 12

A pulse transformer for firing thyristors as defined in claim 9, wherein each of said first conductive layers are kept at an equal potential with that of the surface portion of the insulating body of the corresponding transformer unit, and the innermost layer of said second conductive layers being electrically connected to the nearest first conductively layer so as to form a series of electrostatic capacitive couplings in the axial direction of said insulating cylinder.

Claim 13

A pulse transformer for firing thyristors as defined in claim 10, wherein said primary conductor is formed of non-magnetic material in the form of an integral hollow cylinder through which an energizing cable is inserted, thereby physically reinforcing said insulating cylinder.

Claim 14

A pulse transformer for firing thyristors comprising a primary conductor conductively connected to a pulse generator, an insulating cylinder divided into a plurality of portions in axial direction, said primary conductor extending through said insulating cylinder, and a plurality of transformer units fitted around said primary conductor through said insulating cylinder therebetween, each of said transformer units including a magnetic iron core, a secondary winding wound on said iron core and connected to the gate of a thyristor and in insulating body for insulating said secondary winding the improvement comprising: a first conductive layer disposed in inner peripheral portion of said insulating cylinder and kept at an equipotential to that of said primary conductor; second conductive layers disposed in the inner peripheral portions of said insulating bodies of at least those transformer units which are positioned on the higher voltage side, facing said insulating cylinder; third conductive layers disposed in those surface portions of said insulating cylinder which face said second conductive layers, said second and third conductive layers being electrically connected respectively; said insulating cylinder portions having a converging and a diverging end surface; fourth conductive layers disposed in each facing end portion of said divided cylinder poRtions and electrostatically coupled to respective one of said third conductive layers, the end lines of said fourth conductive layers being offset in a radial direction to form an equipotential surface substantially perpendicular to the facing end surfaces of said insulating cylinder portion.

Claim 15

A pulse transformer for firing thyristors comprising a primary conductor conductively connected to a pulse generator, an insulating cylinder divided into a plurality of portions in axial direction, said primary conductor extending through said insulating cylinder, and a plurality of transformer units fitted around said primary conductor through said insulating cylinder therebetween, each of said transformer units including a magnetic iron core, a secondary winding wound on said iron core and connected to the gate of a thyristor and in insulating body for insulating said secondary winding the improvement comprising: a first conductive layer disposed in inner peripheral portion of said insulating cylinder and kept at an equipotential to that of said primary conductor; second conductive layers disposed in the inner peripheral portions of said insulating bodies of at least those transformer units which are positioned on the higher voltage side, facing said insulating cylinder; third conductive layers disposed in those surface portions of said insulating cylinder which face said second conductive layers, said second and third conductive layers being electrically connected respectively; said insulating cylinder portions having a converging and a diverging end surface; fourth conductive layers disposed in each facing end portion of said divided cylinder poRtions and electrostatically coupled to respective one of said third conductive layers, the end lines of said fourth conductive layers being offset in a radial direction to form an equipotential surface substantially perpendicular to the facing end surfaces of said insulating cylinder portion.

Claim 16

A pulse transformer for firing thyristors as defined in claim 12, further comprising gaps between said primary conductor and said insulating cylinder, and between each pair of adjacent cylinder portions, said gaps being continuous, and a highly insulating medium filled in said gaps.

Claim 17

A pulse transformer for firing thyristors as defined in claim 13, further comprising an upper and a lower vessel respectively attached at the upper and the lower end of said insulating cylinder and an insulating medium contained in said vessel, said gaps being continuous to said upper and lower vessel.