Improvements in or relating to single-phase bridges with semiconductor cells and continuous voltage and current regulation

摘要

1,082,871. Rectifying. CKD PRAHA, NARODNI PODNIK. Jan. 21, 1965 [Jan. 23, 1964], No. 2677/65. Heading H2F. A single-phase bridge has four basic arms 9, 10, 11, 12, each including a semi-conductor rectifier SR1, SR2, SR3, SR4. The arms 9, 10 are each split into two arms 5, 7 and 6, 8, having controlled semi-conductor rectifiers SCR1 . . . SCR4 which are connected in pairs to adjacent tappings (e.g. 1, 2), on transformer Tr via contacts K1 . . . K4. A further pair of uncontrolled rectifiers SR5, SR6 are also connected between points A, B and the lower of the two tappings to which the controlled rectifiers are connected (e.g. 1) by means of contacts k1 . . . k4. When changing tappings, contact K1 is first opened and K3 closed, and subsequently k1 opened and k2 closed, so that the controlled rectifiers are now connected between 2, 3, and the uncontrolled rectifiers are again connected to the lower of the two (i.e. 2).