GB1241822A - Transformers - Google Patents

Abstract

1,241,822. Transformer tap-changes. LICENTIA PATENT - VERWALTUNGS G.m.b.H. 8 July, 1968 [7 July, 1967], No. 32504/68. Headings H1N and H1T. A transformer winding comprises, for each phase, a main winding part 1, a tapped winding 3 having an associated tap-changer 10 and providing fine regulation, and a further regulating winding 2 which can be switched into use when required, the switches being so arranged that when winding 2 is not energized its polarity relative to the main winding may be reversed by connecting its end 35<SP>1</SP> to the main winding end 37<SP>1</SP>. The further winding 2 may be untapped, providing coarse regulation, or it may constitute a second part of the tapped winding Two further windings may be provided, one untapped for coarse regulation and one forming a second part of the tapped winding, separate but co-ordinated switches being provided to reverse their polarities when respectively not energized (Figs. 21, 22, not shown). The transformer may be an autotransformer (Fig. 14, not shown). The switch may comprise two curved contact blades 30<SP>1</SP>, 30<SP>11</SP>, Figs. 2, 11, riveted or screwed to a common insulating member 30 and rotating about a spindle 43. Each fixed contact includes two fingers 41 resiliently engaging either face of the blades 30<SP>1</SP>, 30<SP>11</SP>. The blades bridge adjacent fixed contacts and may take up three different positions which connect (a) windings 1, 2 and 3 in series or (b), (c) windings 1 and 3 in series and one or other end of winding 2 to the point 37<SP>1</SP>. The three switch positions may alternatively be obtained using ganged or separate change-over switches (Figs. 3, 4, not shown). If separate switches are used they may be coordinated by means of gearing, relay control or electronic control.