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).
Investigation into the method of regulation for an engine-driven aero generator with a Mark II regulator.
| Identifier | ExFiles\Box 179\2\ img038 | |
| Date | 9th December 1931 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Wst. c.c. Sg.{Arthur F. Sidgreaves - MD} Hcr. c.c. E.{Mr Elliott - Chief Engineer} Ry. c.c. Rc.{R. Childs} LD. Lr.{Mr Ellor} ORIGINAL. He/wst.4/AD9.12.31. X6130. ENGINE DRIVEN AERO GENERATOR WITH MARK II REGULATOR. We have now investigated the method of regulation employed by the Air Ministry for use with the above generator which we recently tested on one of our Kestrel engines. The regulation is an Air Ministry development carried out at the R.A.E. Farnborough and is intended to supersede the ordinary vibrator contact type of regulator now in common use and mainly with a view to eliminating radio disturbances which are found to be accentuated when vibrator type of regulators are used. This system of electrical generation on aircraft is designed to be operated in conjunction with an accumulator to supply heating and lighting loads. Heating loads, which are usually a large proportion of the generator capacity, are supplied only when the generator is operating, so as to avoid draining the necessarily small accumulator. Lighting loads are connected to the accumulator so as to be continuously available. The accumulator cut out is designed to deal only with lighting loads (up to 20 amps.) and the charging current. Any attempt to draw heavy heating loads from the lighting supply would result in the destruction of the cut-out. The regulator which is of the dynamo electric type, depends for its operation on the accumulator charging current. It is therefore absolutely essential that a properly connected accumulator forms part of the system. The principle of operation of the regulator is as follows :- The regulator is a freely running motor, having its armature connected in series with the field winding of the generator. The field winding of the regulator carries the accumulator current only. The attached drawing shows the connection diagram. When the speed of the generator is high enough to charge the accumulator, the armature and field of the regulator are both energised and the machine revolves thereby inducing a back EMF. in the shunt field circuit of the generator. This back EMF. is dependent on the accumulator | ||