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).
Controlling dynamo output for a chassis electrical system using volt-ampere characteristics and external regulators.
| Identifier | ExFiles\Box 31\1\ Scan137 | |
| Date | 3rd November 1922 | |
| Contd. -5- EFCL/T3.11.22. should be held exactly constant. Neither of these extreme cases, however, is suitable for a chassis system. It is more suitable to control the output of the dynamo to some definite volt-ampere characteristic at some definite point of the system, e.g. at the dynamo terminals on the dynamo or at those on the switchbox. We might, for instance, fix upon 16 volts on open circuit and 12 volts when 12 amperes are being delivered, with a proportional relation for other values. Thus the quantity being regulated is volts + amperes/3 this being maintained in ideal circumstances at the value 16, and the proportion of shunt and series windings being so arranged as to make the volts and amperes of this relative importance. In practice there will be variations from this exact characteristic due to temperature and due to the fact that no governor can act without some slight change in the quantity governed. Such a regulation meets in principle any condition under which a chassis electrical system would be run. This being the case it has always seemed to us that a really reliable external regulator applied to an otherwise shunt machine is worth striving for. We have had experience, more or less as the case may be, with the following external regulators and their respective dynamos :- Contd. | ||