| 摘要 |
PCT No. PCT/EP90/00261 Sec. 371 Date Nov. 6, 1991 Sec. 102(e) Date Nov. 6, 1991 PCT Filed Feb. 16, 1990 PCT Pub. No. WO90/10940 PCT Pub. Date Sep. 20, 1990. In a current transformer arrangement for three-wire three-phase systems, use is made of a single busing transformer (4) arranged on the three-phase side. Two of the total of three phase conductors are pushed through the bushing transformer, specifically either with the same number of turns per unit length and in mutually opposite defined directions or with the same direction and with the ratio of different numbers of turns per unit length of 2:1 or with the same direction and a current flow halved in a phase conductor by a shunt (15). These arrangements prevent the occurrence of a zero resultant magnetic flux. The double secondary voltage produced by a double AW value occurring twice during each period is halved by an electronic correcting circuit. The control commands are derived from suitable control pulses for the thyristors (21-26) of the three-phase bridge circuit (16). Two correcting circuits are specified. The main advantage resides in the considerable saving in current transformer material and thus also in space required.
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