Gate turn-off thyristor stack

Claim 2

A gate turn-off thyristor stack comprising a pair of flat type gate turn-off thyristor elements (31, 32; 41, 42) to be connected in parallel with each other and a pair of flat type diode elements (34, 35; 44, 45).to be connected in direct parallel with the respective gate turn-off thyristor elements, wherein all the elements are stacked with electrical connection between the adjacent elements so that the elements in one of the gate turn-off thyristor element pair and the diode element pair are located opposite to each other at the middle of the stack structure and are sandwiched by the associated elements in the other pair which are provided on both sides of the stack structure, respectively, and the resulting stack structure is clamped by a pair of clamper members (62, 63).

Claim 3

A gate turn-off thyristor stack according to claim 1, wherein an electrically conductive heat dissipating member (55; 56; 57; 58) is interposed only between the gate turn-off thyristor element and the associated diode element adjacent thereto.

Claim 4

A gate turn-off thyristor stack according to claim 1, wherein said one pair located at the middle of the stack structure is the diode element pair and said other pair provided on the both sides of the stack structure is the gate turn-off thyristor element pair.

Claim 5

A gate turn-off thyristor stack according to claim 1, wherein said one pair located at the middle of the stack structure is the gate turn-off thyristor element pair and said other pair provided on the both sides of the stack structure is the diode element pair.

Claim 6

A gate turn-off thyristor stack comprising two arms (3, 4) which are to be connected in series with each other and each of which include a pair of flat type gate turn-off thyristor elements (31, 32; 41, 42) to be connected in parallel with each other and a pair of flat type diode elements (34, 35; 44, 45) to be connected in direct parallel with the respective gate turn-off thyristor elements, wherein all the elements in each of said two arms are stacked with electrical connection between the adjacent elements so that the elements in one of the gate turn-off thyristor element pair and the diode element pair are located opposite to each other at the middle of the stack structure and are sandwiched by the associated elements in the other pair which are provided on both sides of the stack structure, respectively, said two arms each having the stack structure are integrally series-assembled with an insulating member (51) interposed therebetween, and the resulting assembly is clamped by a pair of clamper members (62, 63).

Claim 7

A gate turn-off thyristor stack comprising two arms (3, 4) which are to be connected in series with each other and each of which include a pair of flat type gate turn-off thyristor elements (31, 32; 41, 42) to be connected in parallel with each other and a pair of flat type diode elements (34, 35; 44, 45) to be connected in direct parallel with the respective gate turn-off thyristor elements, wherein all the elements in each of said two arms are stacked with electrical connection between the adjacent elements so that the elements in one of the gate turn-off thyristor element pair and the diode element pair are located opposite to each other at the middle of the stack structure and are sandwiched by the associated elements in the other pair which are provided on both sides of the stack structure, respectively, said two arms each having the stack structure are integrally series-assembled with an insulating member (51) interposed therebetween, and the resulting assembly is clamped by a pair of clamper members (62, 63).

Claim 8

A gate turn-off thyristor stack according to claim 5, wherein each of said two arms includes other semiconductor element (39; 49) and said two arms are integrally series-assembled including the respective other semiconductor elements.

Claim 9

A gate turn-off thyristor stack according to claim 5, wherein an electrically conductive heat dissipating element (55; 56; 57; 58) is disposed only on one side surface of the gate turn-off thyristor element.