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).
Modifications to external regulator controls for dynamo battery systems, comparing different regulation methods.
| Identifier | WestWitteringFiles\V\December1930-February1931\ Scan152 | |
| Date | 9th January 1931 guessed | |
| -3- It may be considered that it is for this reason that there have been from time to time proposed, modifications of external regulator control in which the regulating action does not take place on the contacts continuously i.e. regulating the field current always in accordance with momentary demand, but alternatively by making use of the storage capacity of the battery allowing the field current to be varied between its full amount and some lower amount determined by a suitable resistance in parallel with the contacts in series with the field winding, with a period of opening and closing perhaps many thousand times larger than the periodicity of dithering contacts. In the long run the average field current may be considered to be the same so that such a system may be looked upon as a long period vibrator regulator, making use of battery storage capacity and producing in the long run the same average result. The likelihood of failure to maintain contact for full output is no greater than in the case of dithering contacts and probably less because there is the advantage that the duty of the contacts is greatly reduced. The main fault of the dithering contact method is the variability of the output control in similar battery, dynamo and load circumstances. The long period control must of necessity be utilised in a dynamo battery system which already has inherent control, otherwise the period of operation, although much shorter, would not be short enough to eliminate fluctuations. In the emergency of disconnected battery such a system acts in this manner and gives the necessary warning but otherwise without causing any harm. If considered of any value it would probably be possible to make the experiment of adapting a Bosch type of regulator (regulator only not cut-out) to our existing system but the fact of the foreign origin of such a unit would, we suppose, be considered a serious drawback against its ultimate standardisation. An external vibrator regulator control with dithering contacts should not be looked upon necessarily as "voltage" control as it is possible by suitable proportional provision of compound winding to arrange it to work to any desired volt ampere output characteristic and even in the extreme case to constant current, if desired. | ||