SU1234248A1 - Arrangement for power supply of alternating current electrified railways - Google Patents

Description

The invention relates to electrified AC railways and is intended to supply traction loads on an AC system of 27.5 kV or 2 x 25 kV.

The purpose of the invention is to save energy by balancing the currents in the transmission line.

FIG. 1 shows a circuit diagram of the device; in fig. 2 is a graph of the asymmetry coefficient (cC |) of the currents versus the ratio of the currents of the first and second feeder zones for various power supply device diagrams.

The device for powering electrified

The AC railways contain a three-phase transformer 1, the primary winding of which is connected to the wires of the phases of power line 2, and one output of the secondary winding is connected to the first feeder zone 3 of the contact network, which is separated by a neutral insert 4, the other is connected to rails 5, and a single-phase transformer 6 The terminals of the secondary winding of which are connected to the second feeder zone 7 of the contact network and the rail 5, and the primary is connected to the wires of power line 2 that do not coincide with the phase of the first feeder zone 3 of the contact tnoj network, the other terminal of the secondary winding of the three-phase transformer 1 is disconnected from the second feeder band 7 catenary.

The device works as follows.

The voltage in the contact network of the first feeder zone 3 is VA, and the voltage in the contact network of the second feeder zone 7 is

0

five

Vbc Thus, these voltages form an orthogonal system of vectors, which leads to a significant decrease in negative sequence currents. In particular, with the same load on both feeder zones 3 and 7, the value of the negative sequence current in power transmission line 2 is zero.

The above characterizes the dependence of the asymmetry coefficient (cti) of currents on the ratio of load currents n to the first and second feeder zones 3 and 7 for various power supply devices.

For), 5-1.5 when using the proposed device “1 decreases, when to zero, when n 0.5 ai decreases 1.73 times, and when n 1.5 - 2.64 times. Thus, the proposed device reduces the asymmetry of currents in power lines x 2 by an average of 4-6 times.

The reliability of the power supply device can also be ensured by the fact that when organizing cantilever power supply with a neutral insert 4 section on the partitioning post and connecting the free output of the secondary winding of the transformer 1 through a normally disconnected switch with a contact suspension of the second feeder zone 7, the three-phase transformer 1 reserves a single-phase one. At the same time, in the power supply device, it is enough to have in reserve one three-phase transformer 1, from which no other consumers (DPR, LEP-35 kV) can normally feed.

The power device can be mounted using typical power and switching equipment.

Power supply from transformers according to scheene / prototype

Power supply on offer / ffeHHOMy device

(Pi / r. 2

Compiled by V. Kochetkov Tehred I. VeresKorrektor S. Cherni

Circulation 647Subscribe

VNIIPI USSR State Committee

for inventions and discoveries

113035, Moscow, Zh-35, Raushsk nab. 4/5

Branch PPP "Patent, Uzhgorod, st. Project, 4

Claims (1)

DEVICE FOR POWERING AC ELECTRICIZED RAILWAYS, containing a three-phase transformer, the primary winding of which is connected to the phase wires of the power line, and one terminal of the secondary winding is connected to the first feeder zone of the contact network, separated by a neutral insert, and the other to rails, characterized in that, in order to save energy by balancing the currents in the power line, it is equipped with a single-phase transformer, the terminals of the secondary winding of which are connected to the second feeder zone, contact network and rail, and the primary is connected to the wires of the power line with phases that do not coincide with the phase of the first feeder zone of the contact network. Figure 1