GB1416561A - Semiconductor arrangements and cooling means therefor - Google Patents

Abstract

1416561 Thyristor converters SIEMENS AG 22 Jan 1973 [22 Jan 1972] 3257/73 Heading H1K A converter circuit, e.g. for A.C.-D.C. or D.C.-A.C. comprises 12 controllable semiconductor thyristors respectively connected in three series pairs in one surge and three in the opposed sense between the unidirectional outputs, with the alternating phase conductors connected successively to the junction of the pairs. Component plates 15a 1 , 15 a2 ; 15b 1 , 15b 2 &c. (Figs. 1, 2) forming parts of corresponding assemblies have resilient springs 23 therebetween corresponding with the axially aligned semiconductive thyristor components 1, 2 in sandwich form gripped between outer contact plates 13, 14 in unitary arrangements. Thus the semiconductor components 1, 3, 5, 7, 9, 11 have terminals electrically commoned over plate 13 and semiconductor components 2, 4, 6, 8, 10, 12 have terminals commoned over contact plate 14. Insulant walls 22 separate the plates 13, 14 which are held together by rigid insulant clips 29. The resilient members 23 are covered by conductive coppered steel mesh shrouds to establish a resilient electrical connection between plates 15a 1 , 15a 1 ; 15b 1 , 15b 2 , &c., interconnected in adjacent pairs by elastic connecting members 21 while remaining thyristors are similarly inter-connected. The walls 22 define inner cooling channels through which insulant cooling liquid may pass in the sense of arrows 18. The contact plates may be finned and the coolant may circulate round the periphery of the individual units, which may comprise thirtysix thyristor units for frequency multiplications; one of the contact plates being insulatedly subdivided (Figs. 3a, 3b, 3c, not shown). The coolant circuit may be closed to permit boiling, or open to permit circulation. In a modification in which the semiconductor assembly is unitary with its A.C. feed source (Figs. 4a, 4b) a transformer 27 energizes a sequentially connected direct frequency changer, and its tank wall 14a serves as a thermal contact plate and a common neutral. Secondary connections 28 extend through insulant bushes 14d of the wall to thyristors 1, 2, &c. interposed between an outer contact plate 13 divided into insulated sections 13a, 13b, 13c providing the A.C. outputs; the tank wall 14a, and inner contact plates 15a 1 , 15a 2 , &c. being separated by the resilient member. The tank contains an oil coolant which flows through aperture 30 of the wall to surround and cool the thyristors, and sections 13a, 13b, 13c may have cooling fins 24 extending outwardly thereof. Alternatively the thyristor assembly (Fig. 4c) may be mounted on a separate contact plate 14 carried by wall 14a, arranged so that the assembly may be plugged into the A.C. source through an interposed insulant plate 14e by means of insulated sockets 31 in wall 14a engaging pins 32 of the thyristor assembly; a tube 33 of the latter engaging an aperture 30 of the transformer tanks, arranged to open only when the assembly is plugged in.