Patent GB-190722581-A (GB)
Title: Improvements in Electric Battery Substations Fed from Alternating Current Systems.
Inventor: TAYLOR ALFRED MILLS
IPC: H02J3/32
Filed: 1907-10-14
Granted: 1909-01-14
Abstract: 22,581. Taylor, A. M. Oct. 14. [Cognate Applications No 26,381, A.D. 1907, dated Nov. 29, and No. 1734, A.D. 1908, dated Jan. 25.] Distributing.-The sub-stations of alternating- current distribution systems are provided with a number of battery-charging units adapted to transmit energy from high-potential alternating-current mains to battery units, which are placed in series and discharged through intermediate rotary converting-apparatus to the continuous-current load circuit, or to high-pressure alternating-current mains. The high-potential supply mains a are connected to rotary converters d through static transformers e<2>, and to the direct-current load circuit b through transformers e and rotary converters f. The rotary converters d are connected to battery units c through boosters g; or, alternating-current boosters may be placed between the transformers e<2> and rotary converters d. The transformers e' may be provided with taps for varying the voltage supplied to the rotary converters d, which are quadruple or octuple wound with two of the windings brought out at each side of the armature and connected to a commutator, the two commutators and four windings being initially connected in parallel and finally in series. When the load on the sub-station is sufficient, the battery units are placed in series, as shown in Fig. 2, in which some of the rotary converters d are retained as boosters d<1>, while others are reconnected so that all four armature windings are in series as in d<2> and placed on either side of the neutral wire of the load circuit b. In a modification, the load circuit b is connected to the highpressure mains through a static transformer and rotary converter, coupled to which is a low-voltage generator connected to a battery unit; or, the static transformer and converter may be replaced by a motor-converter. In another modification, the direct-current side of the converter is connected to a battery unit, and the converter drives a generator or two generators in series for feeding the load circuit b ; or, the converter and transformer feeding it may be replaced by a motor-converter. In other modifications, the high-pressure mains feed an induction motor - generator coupled to another generator which may feed a battery unit or the direct-current load circuit b ; or, the motorgenerator may feed the load circuit b, the battery unit being connected to the supply mains through a transformer and rotary converter. In the arrangement shown in Fig. 11, means are provided for reducing the electromotive force upon the directcurrent side of the converter by varying the windings of the transformer and the excitation of the converter. By connecting the windings of the doubly-wound secondary of the transformer in parallel and reducing the field of the converter to one-half its ultimate strength, the converter may be used to charge a battery unit c of half the voltage of the direct-current side, by connecting one pole of the battery to the commutator of the converter and the other pole by a neutral wire to the centre of the transformer secondary. When a second battery unit is added upon the growth of the sub-station, it is put in series with the first and connected across the commutators of the converter d still running on half its full field strength. With the addition of a third unit, a second charging-unit may be added ; or, the three battery units may be connected in series, and the field of the converter increased to three - quarter strength, or to full strength when a fourth unit is added. In the final arrangement, the voltage of the converter may be doubled and placed across the load circuit b ; or, it may be connected in parallel with a similar machine as a booster in series with the full battery voltage. Reference is made to Specifications No. 18,812, A.D. 1888, and No. 9602, A.D. 1890; and No. 3677, A.D. 1906, [Abridgment Class Rotary engines &c.], and to systems for equalizing the load upon alternating-current generators by means of a storage battery, rotary converter, and booster.