GB376869A - Improvements in or relating to methods of and apparatus for deriving power from high-voltage lines - Google Patents

Abstract

376,869. Supplying low voltage apparatus; condensers. WESTING- HOUSE ELECTRIC & MANUFACTURING CO., East Pittsburg, U.S.A.-(Assignees of Peters, J. F. ; 405, Hutchinson Avenue, and Marbury, R. E. ; 419W, Hutchinson Avenue, Edgewood, Pennsylvania, U.S.A.) May 1, 1931, No. 12885. Convention date, May 1, 1930. [Classes 38 (ii) and 38 (iv).] In a method for obtaining low voltage power from high voltage alternating current overhead transmission lines 4, an inductance 5 and the load 7 are shunted across one 1 of a number of series connected capacitor units so that the capacitor, inductance and load form a substantially resonant circuit wherein a relatively large current of relatively low voltage can be obtained, whilst a relatively small current only is drawn from the transmission line. In a modification the primary winding of a transformer is introduced into the resonant circuit, the load being arranged in the secondary circuit of this transformer. Fig. 3 illustrates a desirable form of suspension capacitor unit which comprises a cylindrical casing 11 of porcelain with a cap 12 and a base 13, the units being linked together by projections 14 engaging orifices 15 in the caps. In an interior cylinder 16 of insulating material and with liquid tight end caps, are placed the condenser units 17, each formed of strips of metal foil and paper wound on a core of fibreboard and immersed in insulating wax, the container 16 being then filled with insulating oil. The units 17 are mounted in series upon a base plate 18 and separated by insulating spacers 19. The linked capacitor units may support the line conductor and thus function also as a line suspension insulator, or they may themselves be suspended from suspension insulators and connected at the upper end to the line conductor.