Power supply and three-phase load

FIELD: electrical engineering.

SUBSTANCE: two engineering solutions are proposed which are characterized in common engineering goal and common approach to solution. Power supply has transformer incorporating primary windings 1, magnetic core 2, and secondary windings 3; connected in series with the latter is diode bridge 4 closed through poles to reactor coils 5 and 6. Novelty is that central lead of reactor coils 5 and 6 is connected to neutral of load 7. The latter is connected to supply mains through switch 8. Diode bridge with similar double-coil reactor is inserted in series with neutral of all three phases of three-phase load. Novelty in this alternative is that reactor center tap is connected to neutral of supply mains. Damping (smoothing down current peaks) is effected both when three-phase and single-phase loads are connected.

EFFECT: enlarged functional capabilities, ability of damping inrush load currents.

2 cl, 2 dwg

 

The invention relates to the field of electrical engineering. The proposed two technical solutions, common technical purpose and General approach of the solution.

The closest to the technical essence and the achieved results is the power supply [1], containing the transformer to the outputs of the ends of the secondary winding of which is connected to the load, and start winding is connected to a diode bridge, to the poles of which is connected to the reactor. The disadvantage of this device is limited in functionality, since it applies only for loads that do not use the neutral wire.

Closest to the technical essence and the achieved results of the second variant of the invention is a three-phase load [1], the inputs of the three phases which are connected to the switch, and the conclusions connected to the diode bridge, the poles of which is connected to the reactor. The drawback of the device, as above, is limited in functionality, as it can only be used for loads that do not use the neutral wire.

The aim of the invention is the extension of functionality through the use of for loads using the neutral wire.

This goal is achieved in the power supply due to the fact that the reactor is equipped with intermediate output, attached is atruly load.

This goal is achieved in the second embodiment of the invention three - phase load due to the fact that the reactor is equipped with an average output is connected to the neutral network.

Figure 1 presents the scheme of the power supply.

Three-phase transformer includes a primary winding 1, the magnetic circuit 2 and the secondary winding 3, the initial conclusions of which is connected a diode bridge 4. Pole of the latter is connected with two series-connected windings 5 and 6 of the reactor. The reactor may be of the magnetic or running air. The final conclusions of the winding 3 of the transformer connected to the load 7 (conclusions of phases a, b, C). Neutral N load 7 is connected to the middle point of the windings of the reactor 5 and 6.

Figure 2 presents the scheme of the three-phase load.

The actual payload 7 contains three phases. In rassechku neutral load included a three-phase diode bridge 4, the poles of which are connected windings 5 and 6 of the reactor. Neutral N network connected to the middle point of the windings 5 and 6 of the reactor. Input load 7 connected to the switch 8, is connected to the network (phase a, b, C). The switch 8 connects and disconnect loads to the network.

The devices work as follows. The transformer receives the winding 1 energy from the network and passes it through the magnetic core 2 in the secondary winding 3, which, in turn, under the Ute power to the load 7. The entire flow of energy passes through the diode bridge 4 and the reactor windings 5 and 6. The windings 5 and 6 of the reactor have a damping effect on the load currents, limiting its peaks when the races of the load and the network, reduce the rate of current rise. The same damping effect of the reactor windings 5 and 6 has a connecting loads 7. The specified damping (smoothing peak current) is carried out for both three-phase and single-phase loads, which confirms the objectives of the invention. Power supply and three-phase load can be used together and separately.

The source of information

1. USSR author's certificate No. 1471245. The device for feeding electric arc furnace. CL. H 02 J 3/00, N 05 In 137/144, B, 1989, No. 13.

1. The power supply contains a transformer to the outputs of the ends of the secondary winding of which is connected to the load, and start winding is connected to a diode bridge, to the poles of which is connected to the reactor, wherein the reactor is equipped with a secondary output is connected to the neutral of the load.

2. Three-phase load, the inputs of the three phases which are connected to the switch, and the conclusions connected to the diode bridge, the poles of which is connected to the reactor, wherein the reactor is equipped with a secondary output is connected to the neutral network.



 

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