Switching device for on-load tap changers of regulating transformers

Claim 2

A switching device for an onload tap changer of a regulating transformer, comprising a plurality of first vacuum switches each connected directly to one of a plurality of first tap selectors corresponding to the odd-numbered taps of the tap winding for each phase of a three-phase voltage at one terminal and to a common terminal at the other terminal, a plurality of second vacuum switches each connected to said first tap selector through a current limiting element at one terminal and to said common terminal at the other terminal, a plurality of third vacuum switches each connected directly to one of a plurality of second tap selectors corresponding to the even-numbered taps of the tap winding for said phase at one terminal and to said common terminal at the other terminal, said vacuum switches being arranged along the sides of a regular polygon, with those vacuum switches which are operated at the same time in a switching sequence being located on one and the same side of said polygonal shape in a group, and means for opening and closing the vacuum switches in each group all at once in accordance with a predetermined switching sequence.

Claim 3

A switching device for an onload tap changer of a regulating transformer, comprising a plurality of first vacuum switches each connected directly to one of a plurality of first tap selectors corresponding to the odd-numbered taps of the tap winding for each phase of a three-phase voltage at one terminal and to a common terminal at the other terminal, a plurality of second vacuum switches each connected to said first tap selector through a current limiting element at one terminal and to said common terminal at the other terminal, a plurality of third vacuum switches each connected directly to one of a plurality of second tap selectors corresponding to the even-numbered taps of the tap winding for each phase at one terminal and to a common terminal at the other terminal, a plurality of fourth vacuum switches each connected to said second tap selector through a current limiting element at one terminal and to said common terminal at the other terminal, said vacuum switches being arranged along the sides of a regular polygon with those vacuum switches which are operated at the same time in a switching sequence being located on one and the same side of said polygonal shape in a group, and means for opening and closing the vacuum switches in each group all at once in accordance with a predetermined switching sequence.

Claim 4

A switching device for an onload tap changer of a regulating transformer, comprising a plurality of first vacuum switches each connected directly to one of a plurality of first tap selectors corresponding to the odd-numbered taps of the tap winding for each phase of a three-phase voltage at one terminal and to a common terminal at the other terminal, a plurality of second vacuum switches each connected to said first tap selector through a current limiting element at one terminal and to said common terminal at the other terminal, a plurality of third vacuum switches each connected directly to one of a plurality of second tap selectors corresponding to the even-numbered taps of the tap winding for each phase at one terminal and to a common terminal at the other terminal, a plurality of fourth vacuum switches each connected to said second tap selector through a current limiting element at one terminal and to said common terminal at the other terminal, said vacuum switches being arranged along the sides of a regular polygon with those vacuum switches which are operated at the same time in a switching sequence being located on one and the same side of said polygonal shape in a group, and means for opening and closing the vacuum switches in each group all at once in accordance with a predetermined switching sequence.

Claim 5

A switching device for an onload tap changer of a regulating transformer as defined in claim 2, in which said first and said third vacuum switches which are connected directly to each of the first and second tap selectors for the respective phases are one in number and said second and said fourth vacuum switches which are connected to each of said first and second tap selectors through a current limiting element respectively are at least one in number, all of said vacuum switches being segregated into four groups, a first group consisting of said first vacuum switches which are connected to the first tap selector for each phase directly, a second group consisting of said second vacuum switches which are connected to said first tap selector through a current limiting element respectively, a third group consisting of said third vacuum switches which are connected to the second tap selector for each phase directly and a fourth group consisting of said fourth vacuum switches which are connected to said second tap selector through a current limiting element respectively, and said groups of vacuum switches being arranged in such a manner that one group is located on one side of the polygonal shape independently of the other groups.

Claim 6

A switching device for an onload tap changer of the regulating transformer as defined in claim 2, in which said first and said third vacuum switChes which are connected directly to each of the first and second tap selectors for the respective phases are at least two in number and are connected with each other in parallel, while said second and said fourth vacuum switches which are connected to each of said first and second tap selectors through a current limiting element respectively are provided in the same number as the number of said first vacuum switches and are connected with each other in parallel.

Claim 7

A switching device for an onload tap changer of a regulating transformer, comprising a first pair of vacuum switches each connected to one of a pair of tap selectors selectively connectable with one of the taps of the related tap winding of the transformer at one terminal and to a common terminal at the other terminal, at least one second pair of vacuum switches each connected to one of said pair of tap selectors through a current limiting resistor at one terminal and to said common terminal at the other terminal, an insulating housing for accommodating said vacuum switches and said current limiting resistors, and means for opening and closing said vacuum switches in accordance with a predetermined switching sequence, said vacuum switches being disposed in said insulating housing, with those vacuum switches which are operated in the same switching sequence being located on one and the same side of a regular polygonal shape.

Claim 8

A switching device for an onload tap changer of a regulating transformer, comprising a first pair of vacuum switches each connected to one of a pair of tap selectors selectively connectable with one of the taps of the related tap winding of the transformer at one terminal and to a common terminal at the other terminal, at least one second pair of vacuum switches each connected to one of said pair of tap selectors through a current limiting resistor at one terminal and to said common terminal at the other terminal, an insulating housing for accommodating said vacuum switches and said current limiting resistors, and means for opening and closing said vacuum switches in accordance with a predetermined switching sequence, said vacuum switches being disposed in said insulating housing, with those vacuum switches which are operated in the same switching sequence being located on one and the same side of a regular polygonal shape.

Claim 9

A switching device for an onload tap changer of the regulating transformer as defined in claim 5, having a plurality of said second pairs of vacuum switches connected to current limiting resistors, in which pairs of the vacuum switches and the current limiting resistors are arranged for operation in the same switching sequence and all vacuum switches are disposed in the insulating housing in two vertical steps, with those which are operated in the same switching sequence being connected with each other in parallel.

Claim 10

A switching device for an onload tap changer of the regulating transformer as defined in claim 5, having a plurality of first pairs of vacuum switches in which pairs of the vacuum switches are disposed in the insulating housing in two vertical steps, with those which are operated in the same switching sequence being connected with each other in parallel.

Claim 11

A switching device for an onload tap changer of the regulating transformer as defined in claim 5, having a plurality of said second pairs of vacuum switches connected to current limiting resistors, in which pairs of the vacuum switches and the current limiting resistors are connected in parallel for operation in the same switching sequence, respectively, and one of said vacuum switches connected with each other in parallel and one of said current limiting resistors connected with each other in parallel are disposed in one of a pair of juxtaposed insulating housings, while the other one of said vacuum switches and the other one of said current limiting resistors are disposed in the other one of said current limiting resistors are disposed in the other one of said insulating housings.

Claim 12

A switching device for an onload tap changer of the regulating transformer as defined in claim 5, in which three insulating housings, respectively, accommodating the vacuum switches and the current limiting resistors are vertically juxtaposed in three steps, each for each phase of a three-phase voltage.

Claim 13

A switching device for an onload tap changer of the regulating transformer as defined in claim 5, in which three insulating housings, respectively, accommodating the vacuum switches and the currency limiting resistors are arranged side-by-side horizontally, each for each phase of a three-phase voltage.

Claim 14

A switching device for an onload tap changer of a regulating transformer, comprising a first vacuum switch connected directly to a first tap selector selectively connectable with the odd-numbered taps of the related tap winding of the transformer at one terminal and to a common terminal at the other terminal, at least one sEcond vacuum switch connected to said first tap selector through a current limiting resistor at one terminal and to said common terminal at the other terminal, a third vacuum switch connected directly to a second tap selector selectively connectable with the even-numbered taps of said tap winding at one terminal and to said common terminal at the other terminal, at least one fourth vacuum switch connected to said second tap selector through a current limiting resistor at one terminal and to said common terminal at the other terminal, an insulating housing for accommodating said first vacuum switch and said fourth vacuum switch, and another insulating housing for accommodating said second vacuum switch and said third vacuum switch, and means for opening and closing said vacuum switches in sequence from the first vacuum switch to the fourth vacuum switch in accordance with a tap switching sequence.

Claim 15

A switching device for an onload tap changer of a regulating transformer, comprising a first vacuum switch connected directly to a first tap selector selectively connectable with the odd-numbered taps of the related tap winding of the transformer at one terminal and to a common terminal at the other terminal, at least one sEcond vacuum switch connected to said first tap selector through a current limiting resistor at one terminal and to said common terminal at the other terminal, a third vacuum switch connected directly to a second tap selector selectively connectable with the even-numbered taps of said tap winding at one terminal and to said common terminal at the other terminal, at least one fourth vacuum switch connected to said second tap selector through a current limiting resistor at one terminal and to said common terminal at the other terminal, an insulating housing for accommodating said first vacuum switch and said fourth vacuum switch, and another insulating housing for accommodating said second vacuum switch and said third vacuum switch, and means for opening and closing said vacuum switches in sequence from the first vacuum switch to the fourth vacuum switch in accordance with a tap switching sequence.

Claim 16

A switching device for an onload tap changer of the regulating transformer as defined in claim 11, in which said insulating housings are juxtaposed vertically in two steps.

Claim 17

A switching device for an onload tap changer of the regulating transformer as defined in claim 11, in which said insulating housings are arranged side-by-side horizontally.

Claim 18

A switching device for an onload tap changer of the regulating transformer as defined in claim 11, in which two of said second vacuum switches, two of said current limiting resistors connected to said respective second vacuum switches, two of said fourth vacuum switches and two of said current limiting switches connected to said respective fourth vacuum switches are provided.

Claim 19

A switching device for an onload tap changer of the regulating transformer as defined in claim 11, in which three of said second vacuum switches, three of said current limiting resistors connected to said respective second vacuum switches, three of said fourth vacuum switches and three of said current limiting switches connected to said respective fourth vacuum switches are provided.

Claim 20

A switching device for an onload tap changer of the regulating transformer as defined in claim 11, in which said first vacuum switch, said second vacuum switch, said third vacuum switch and said fourth vacuum switch are disposed in an insulating housing common for all phases of three-phase voltage.

Claim 21

A switching device for an onload tap changer of a regulating transformer, comprising a first vacuum switch group consisting of three vacuum switches each connected directly to a first tap selector for each phase selectively connectable with the odd-numbered tap group of the tap winding for each phase of three-phase voltage at one terminal and to a common terminal at the other terminal, a second vacuum switch group consisting of vacuum switches in a number being a multiple of three each connected to said first tap selector through a current limiting resistor at one terminal and to said common terminal at the other terminal, a third vacuum switch group consisting of three vacuum switches each connected directly to a second tap selector for each phase selectively connectable with the even-numbered tap group of said tap winding at one terminal and to said common terminal at the other terminal, a fourth vacuum switch group consisting of vacuum switches in a number being a multiple of three each connected to said second tap selector through a current limiting resistor, an insulating housing in which said first vacuum switch group, said second vacuum switch group, said third vacuum switch group and said fourth vacuum switch group are arranged each along one side of a square shape, a drive shaft located at the center of said square within said insulating housing and supported by said insulating housing for reciprocative rotation through a predetermined angle, a plurality of levers each having one end supported eccentrically by said drive shaft and a plurality of link mechanisms each having one end operatively connected to the other end of each of said levers through a slotted link and the other end operatively connected to each of said vacuum switch group.

Claim 22

A switching device for an onload tap changer of a regulating transformer, comprising a first vacuum switch group consisting of three vacuum switches each connected directly to a first tap selector for each phase selectively connectable with the odd-numbered tap group of the tap winding for each phase of three-phase voltage at one terminal and to a common terminal at the other terminal, a second vacuum switch group consisting of vacuum switches in a number being a multiple of three each connected to said first tap selector through a current limiting resistor at one terminal and to said common terminal at the other terminal, a third vacuum switch group consisting of three vacuum switches each connected directly to a second tap selector for each phase selectively connectable with the even-numbered tap group of said tap winding at one terminal and to said common terminal at the other terminal, a fourth vacuum switch group consisting of vacuum switches in a number being a multiple of three each connected to said second tap selector through a current limiting resistor, an insulating housing in which said first vacuum switch group, said second vacuum switch group, said third vacuum switch group and said fourth vacuum switch group are arranged each along one side of a square shape, a drive shaft located at the center of said square within said insulating housing and supported by said insulating housing for reciprocative rotation through a predetermined angle, a plurality of levers each having one end supported eccentrically by said drive shaft and a plurality of link mechanisms each having one end operatively connected to the other end of each of said levers through a slotted link and the other end operatively connected to each of said vacuum switch group.

Claim 23

A switching device for an onload tap changer of the regulating transformer as defined in claim 17, in which the vacuum switches in each of said vacuum switch groups are connected by a common pressing lever which is operatively connected with each of said link mechanisms.

Claim 24

A switching device for an onload tap changer of the regulating transformer as defined in claim 17, in which each of said link mechanisms is provided with means for constantly urging the vacuum switches in the associated vacuum switch group in an opening direction.

Claim 25

A switching device for an onload tap changer of the regulating transformer as defined in claim 18, in which said pressing lever is provided with a spring for constantly urging the vacuum switches in the associated vacuum switch group in an opening direction.

Claim 26

A switching device for an onload tap changer of the regulating transformer as defined in claim 17, in which each of the vacuum switches in each vacuum switch group is provided with means by which said vacuum switch is constantly urged in an opening direction.

Claim 27

A switching device for an onload tap changer of the regulating transformer as defined in claim 17, in which the respective ends of said levers are eccentrically supported on supporting points of said driving shaft, said supporting points being disposed that the respective angular positions of the lines connecting said supporting points with the center of said driving shaft are successively varied in a same direction by a predetermined angle with respect to the lines connecting the middle points of the corresponding sides of said square with said center.