From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Technical discussion on optimizing an electric motor's design by adjusting its electrical and magnetic circuits, including the armature, field winding, and air gap.
| Identifier | ExFiles\Box 64\2\ scan0167 | |
| Date | 30th June 1928 guessed | |
| -2- Contd. up the conductance of the electric circuit on the one hand and the permeance of the magnetic circuit on the other. As regards the armature it so happens that the electrical resistance of this unit does agree with the calculated amount, and it may be impossible to improve this without interfering with the magnetic permeance of that component. In any case, it would probably be preferable, if anything can be done at all, to leave the electrical resistance as it is and improve the magnetic permeance by reducing the slot dimensions at the expense of insulation. In regard to the field winding, whatever number of turns eventually turns out to be best, it is most essential that we keep the resistance of this item down to the lowest possible figure consistent with the number of turns provided. In regard to the remainder of the magnetic circuit, the principal item, i.e. air gap, should be the minimum possible amount. In the one motor of this type which has been made so far there appear to be some discrepancies in the magnetic circuit in regard to the taper and resulting air gap, which discrepancies we are taking up with Mr. Davis with a view to elucidation. In order to arrive at the best ~~possi~~ result obtainable in the circumstances of the case, we consider it necessary to ~~make~~ have for experiment a motor of this type arranged purely as an experimental machine and largely only from the point of view of the efficiency and performance of | ||