SU748649A1 - Electric power supply device - Google Patents

Description

one - .

  The invention relates to electrical engineering, primarily to the design of pisanin and electric power distribution schemes, in particular, circuits of smooth and distribution networks of alternating current, and can be applied to supply electricity to industrial enterprises, buildings and structures. A device for power supply of consumers is known; it contains a dual reactor for improving the quality of electrical energy by eliminating the mutual influence of consumers through the internal resistance of the power supply network. The branches of the doubled reactor are turned on and off, and the negative mutual resistance is opposite to the resistance of the supply network.

The disadvantage of this device is that it cannot eliminate the mutual influence of loads at different classes of voltage, for example, when loads are fed from two windings of a three-winding transformer, due to the presence of an electrical connection between the windings of the reactor.

A device containing a supply network, a three-winding transformer and a twin reactor is known, one

the winding of the dual reactor is connected in series with the secondary winding of the transformer, and the second winding. a is connected in series with the tertiary winding. The windings of the dual reactor are not electrically connected. Such a connection of the transformer with the reactor makes it possible to eliminate the mutual influence of loads at the same connections of the secondary and tertiary windings of the transformer, for example, at connections X / L or L / L 1.

A disadvantage of the known device is that it cannot eliminate the mutual influence of loads at different connections of transformer windings. This is due to the fact that the voltage drop on the resistance of the mains supply is transmitted on the side of a single load, rotated by an angle "3, defined by the connection of the transformer windings. The EMF induced by the current of another load through the mutual inductance of the reactor does not turn and does not counterphase with a voltage drop, so they are not compensated and the mutual influence of the loads is not eliminated

The purpose of the invention is to eliminate this drawback, i.e. elimination of the mutual influence of loads at different connections of transformer windings.

This goal is achieved by the fact that the device for power supply of pulsating loads of different voltage classes contains a three-phase AC supply network, a three-winding transformer and three single-phase dual reactors, one of the windings of each of which is connected between one load and the secondary winding of the transformer, and the second winding included between the second load and the tertiary winding of the transformer, one of the windings of each single-phase dual reactor is made of two parts, one of which is located en on the magnetic core of the reactor of another phase.

, FIG. 1 and 2 schematically illustrate embodiments of the device.

A three-winding transformer 3 is connected to the power system 1 (Fig. 1) through the internal resistance 2 of the power supply network, the secondary 4 and tertiary 5 windings of which have a different connection. The loads of the first winding 8 of each reactor are connected in series with the load. 7 and the secondary winding 5 of the transformer 3. The second winding of each dual reactor is divided into two parts 9 and 10, with one part Yu placed on the reactor of the other phase. For example, the second part 10 of the second winding of the phase A reactor is placed on the dual reactor of phase B, and the second part 10 of the second winding of the reactor B is placed on the reactor f, you C, etc.

The device operates in the following way. The load current 7 passing through the winding 8 of the twin reactor 6 and the secondary winding 5 of transformer 3 creates a voltage drop across resistance 2. This voltage drop is transmitted to the other load 7 side through the tertiary winding 4 of transformer .3 rotated by the angle "iL, defined by the connection of the winding 4. The same load current 7 simultaneously creates voltage additions on the winding parts 9 and 10. The mutual influence of the loads is eliminated if both the modulus and the voltage drop phase are equal, returned by the angle r and the sum of the voltage additions. To fulfill this requirement, the parameters of the dual reactor must satisfy the conditions:

S j n dk

(cos from "h Xm

lgs

X s i n cK,

Gz

where X is the resistance of mutual inductance between winding 8 and part of winding 9

; mutual inductance between the winding 8 and part of the winding 10f

X. Internal resistance of the mains.

If the resistance of the supply network X varies, then the relationship between the parameters of the reactor and the resistance of the network is broken, and the dual reactor does not fulfill its function. The parameters of the reactor are changed to restore the above ratios. To this end, the windings of each double5. The reactor is seated on a ferromagnetic core 12, which is magnetised by a direct current by the winding 13.

The circuit shown in FIG. one,

0 operates within the range of rotation angle O

In another embodiment (Fig. 2), the second part 10 of the second winding of the dual reactor of phase A is placed on the dual reactor of phase C, and the second part 10 of the second winding of the reactor of phase B is placed on the reactor of phase A, etc.

To eliminate the mutual influence of narruk, the parameters of a twinned reactor are selected, according to the formulas:

D

i i n with / h),

35

The circuit shown in FIG. 2,

operates within the limits of change

) f angle of rotation of Q about b

In the considered variants, a part of the winding 10 is placed on the reactor of another phase. The properties of the device do not change if a part of the winding 9 is placed on the reactor of another phase. another phase.

The proposed device improves the quality of electrical energy 5: and by eliminating the mutual influence of loads in terms of deviations, fluctuations, asymmetries and non-sinusoidal voltages, if the active resistance of the supply network can be neglected.

Claims (2)

1. Author's certificate of the USSR 392586, cl. H 02 J 3/24, 1964. 2. Japanese Patent 52-207, cl. 56 B 1 (H 01 F 31/04), 1977. FI.4 rVFISH