Patent GB-190625289-A (GB)
Title: An Improved Method of Electrical Regulation.
Inventor: BIJUR JOSEPH
Filed: 1906-11-09
Granted: 1907-09-12
Abstract: 25,289. Bijur, J. Nov. 9. -Regulating; switches.-In a system of electric distribution subject to fluctuations of load, the current is maintained at a predetermined value by means of an auxiliary source, of electric supply and an electro-responsive regulator controlling the energy delivered or absorbed by the auxiliary source when the load on the main source of supply varies. A main generator A i s connected t o constant - potential mains B, C, and to variable - potential mains D, E. Lamps F are placed across the mains B, C, while electric motors G and a storage battery H are placed across the mains D, E. A booster I is connected between the main generator A and the storage battery H, the resistance in its field circuit being varied by a regulator J. The regulator J has a constant-pull electromagnet K, the core a and field-magnet b of which have rounded lower ends. The core a is provided with a damping-ring a<1> of copper at its upper end, where there is a substantial air gap between the core and the fieldmagnet, in order to introduce a permanent reluctance, and a rod f passes axially through it and engages with a dash-pot cylinder g. The upper end of the rod f is pivoted to an arm O carried by a rook-shaft P supported upon ball bearings. The shaft P also carries a short upwardly-extending lever Q, the outer end of which engages with a spring R provided with means for adjusting its initial tension. The shaft P projects through the switchboard L, and is provided with another arm S carrying a cross-piece T provided with a series of contact-points s. The contact-points s are arranged to dip successively into a conducting- liquid u contained in a trough t, thereby shortcircuiting portions of the resistance U connected in series with the field winding V of the booster I. Under normal load conditions on the mains D, E, the combined voltage of the generator A and booster I is just equal to the battery voltage, and the current passes to the motors G. When the load on the power mains increases beyond the normal value, the magnet core a is attracted and the arm S raised, thereby cutting resistance into the circuit of the field-winding V. The voltage of the booster is thus reduced to such an extent that the discharge from the battery becomes equal to the excess over the average current taken by the motors. If, however, the load on the power mains decreases below the normal value, the spring R overcomes the pull of the magnet K and the arm S is lowered, thereby cutting resistance out of the circuit of the field winding V of the booster I, increasing the voltage of the booster, and charging the battery H. A resistance is connected in the circuit of the field winding V to limit the exciting-voltage of the booster and so prevent it from developing more than a predetermined maximum voltage when all the regulator resistance U has been cut out. In a modification shown in Fig. 2, the booster I and battery H are connected in series across-the mains, while the rock-shaft P is provided with two arms. Under normal conditions, no potential difference exists between the points 25 and 29, in which case nearly the whole of each resistance U, U<1> is included in the circuit, and no current flows through the field coil 28 of the booster. When the load increases beyond the normal, the magnet K attracts the core a, thereby cutting out some of the resistance U' and raising the potential of the point 25: Current then flows from the point 25 to the point 29 through the field coil 28 of the booster. The direction and amount of the electromotive force is such that the battery is caused to discharge, to compensate for the increase of load. When the load decreases below its normal value, the magnet K is weakened, and the spring R causes some of the resistance U to be cut out and the whole of the resistance U<1> to be put into the circuit. The potential of the point 25 is lowered, and current flows from the point 29 to the point 25, the electromotive force of the booster is reversed, and the battery is charged.