GB769038A - Improvements in or relating to inductive devices - Google Patents

Abstract

769,038. Transformers. BENDIX AVIATION CORPORATION. Nov. 30, 1954 [Dec. 1, 1953; June 9, 1954], No. 34686/54. Class 38 (2). In an inductive coupling, the output voltage of which varies in a desired non-sinusoidal relationship with relative angular movement of primary and secondary windings of the coupling, e.g. as shown in Fig. 3, the secondary winding includes a series of coils lying in slots with the same or a different number of turns N1-N4 and a different slot pitch for each coil, the coils all being symmetrical about an axis normal to the axis of rotation. The coil turns are distributed in a manner which is calculated by a method which involves solving a number of simultaneous equations. Each equation represents a different harmonic of the non-sinusoidal relationship, as derived by analysis into a Fourier series. The unknown quantities of each equation are the number of turns in coils whose number and angular spacing # has been predetermined, the number of equations and of coils being the same. Each equation includes as parameters, functions of the displacement angles, and the coupling factors of the various coils. The latter which depend on the mechanical configuration of the coupling, may be known by experience, or may be determined by iteration, one set of equations with assumed coupling factors being used to obtain turn distributions which are employed in an actual construction of transformer. From the waveform obtained a new set of equations is derived, giving another set of coupling factors. This process may be repeated as necessary. Specifications 671,632 and 680,503 are referred to.