RU106386U1 - DEVICE FOR TESTING PROTECTION OF AC CONTACT NETWORK WITH SHORT CIRCUIT TO BRACKETS DISCONNECTED FROM RAILS - Google Patents

Abstract

1. A device for testing the protection of an alternating current contact network in case of a short circuit on supports disconnected from the rails, including equipment for measuring current, voltage and recording emergency processes, switches installed between the contact network and the earthing switch to reproduce the short circuit mode on the supports of the contact network, which is characterized by that it contains a frame made of two electrically isolated parts from each other, fixed on the support of the contact network, and a control unit for switches, while the equipment for recording emergency processes is located on the site, fixed on one part of the frame and electrically isolated from it, switches and the control unit is located on the other part of the frame, the equipment for measuring current and voltage is mounted on a conductive bus, one end of which is connected to the first switch, and the other end is electrically connected to the body of the contact network support and equipment for recording emergency processes, the second the switch is connected to the contact network using a loop. ! 2. The device according to claim 1, characterized in that the voltage measuring equipment is made in the form of a voltage divider. ! 3. The device according to claim 1, characterized in that the recorder of emergency processes is equipped with an uninterruptible power supply. ! 4. The device according to claim 1, characterized in that the switch control unit is equipped with an uninterruptible power supply. ! 5. The device according to claim 1, wherein the control unit comprises a radio signal receiver.

Description

The utility model relates to a railway power supply system, and in particular to devices for testing the protection of an alternating current contact network against short-circuit currents.

It is known to use the potential protection device of the contact network (PZK) containing a three-electrode spark gap type ZSS with an igniting electrode (short circuit), an ignition transformer, a spark gap, a capacitor, current limiting resistor and disconnector. All constructions installed on the support of the contact network that require grounding are connected to a protective cable connected to the mentioned equipment (Protection of the DC contact network with various methods of grounding the supports Shilkin P.M., Porcelan A.A., Kotelnikov A.V. M. , "Transport", 1977, p. 74, Fig. 33).

A disadvantage of the known device is that it does not provide for operational management and after its operation, the return to the initial state is provided by maintenance personnel. Another disadvantage is the difficulty in maintaining the ignition electrode and the presence of open arc processes. The insulation of this device is designed for a constant voltage of 3.3 kV, while the proposed device should operate under an alternating voltage of 27.5 kV. The use of this device does not mean recording emergency processes. In addition, the device is intended only to increase the sensitivity of the main protection and should be constantly in operation with all the attendant maintenance costs.

The closest known for its technical essence and the achieved result is a device mounted in a test car selected as a prototype for studying emergency operation of traction substations, traction AC networks and relay protection devices (Dynkin EB Protection of traction AC networks during grounding contact network supports: Monograph. - Khabarovsk, DVGUPS, 1999, pp. 66-67, Fig. 2.8), containing measuring current and voltage transformers, recording and switching equipment, including a switch installed between the contact network and the earthing switch, with the help of which the short circuit mode on the earthed supports of the contact network is reproduced.

The disadvantages of the known device include its acquisition of large-sized switching and measuring equipment placed in the car, which must be delivered to the test site along the railway lines, which necessitates long technological windows and restricts the movement of trains throughout the entire test period. In addition, the accuracy of voltage measurement and the electrical safety of personnel during testing are not fully ensured.

The short circuit mode of the traction network is characterized by a sharp increase in the potentials of the rails and emf induced in communication devices and in electrical networks located along the electrified railway line. Therefore, the study of the short circuit mode is of great practical interest for solving the issues of relay protection, ensuring the safety of work and protecting wire lines from dangerous influences (Karyakin R.N. AC traction networks: 2nd ed., Revised and additional - M. : Transport - 1987, p. 55).

This useful model solves the problem of increasing the reliability of power supply to traction consumers and reducing the cost of testing the contact AC circuit protection, including by eliminating the need for lengthy technological “windows” at the time of testing.

The technical result consists in increasing the mobility of the device by ensuring its compactness and autonomy, as well as in improving the accuracy of measuring electrical quantities and electrical safety during testing.

The specified technical result is achieved by the fact that the device for testing the protection of the contact AC network during a short circuit to the supports disconnected from the rails, including equipment for measuring current, voltage and registration of emergency processes, switches installed between the contact network and the ground electrode for reproducing the short circuit mode on the supports contact network, contains a frame fixed to the support of the contact network and the control unit switches. The frame is made of two parts electrically isolated from each other.

The equipment for recording emergency processes is located on the site, mounted on one part of the frame and electrically isolated from it. On the other side of the frame are the switches and the control unit.

The equipment for measuring current and voltage is mounted on a conductive bus, one end of which is connected to the first switch and the other end is electrically connected to the support body of the contact network and equipment for recording emergency processes, the second switch is connected to the contact network by a loop.

This technical result is achieved in particular by the fact that the apparatus for measuring voltage is made in the form of a voltage divider.

The technical result is also achieved by the fact that the device contains a control unit for the switches, and the fact that the control unit contains a receiver of radio signals.

In addition, the emergency process recorder and the circuit breaker control unit are equipped with uninterruptible power supplies.

Compared with the known device for the study of emergency operation of traction substations, traction AC networks and relay protection devices, placed in a test car delivered by rail, the use of the invention allows to increase the reliability of power supply to traction consumers, significantly reduce the cost of equipment and operating costs by reducing time and labor costs for testing, eliminate the need for technological “windows” Restrictions on the movement of trains for a period of testing.

Thanks to the implementation of a device for testing the protection of the contact AC network and its frame mounted on a support of the contact network in the form of a collapsible small-sized design, the mobility of the device and the possibility of transportation to the test production site by vehicles are ensured. Installation time is about 30 minutes. Connecting and disconnecting the cable connecting the circuit breaker to the contact network is carried out in the technological “windows” for no more than 15 minutes each at the time of the absence of trains on the train. After mounting the device, there are no restrictions on the movement of trains.

The implementation of equipment for measuring voltage in the form of a voltage divider compared with the voltage transformer used in the prototype, reduces the dimensions and weight of the equipment, as well as improving the accuracy of voltage measurement.

Due to the remote non-contact control of the circuit breakers via the radio channel, the improvement of labor protection conditions and safety measures is ensured, the possibility of electric shock to personnel is excluded even in the event of breakdown of the circuit breaker insulation relative to their drives.

Equipping the control unit and the recorder of emergency processes with uninterruptible power supplies allows the device to operate autonomously.

The drawing shows a General view of a device for testing the protection of the contact AC network with a short circuit to disconnected from the rails of the support.

The device contains a collapsible metal frame 1, using fasteners secured to the support 2 of the contact network. The frame 1 has a support part adjacent to the support of the contact network and a cantilever part connected to it by means of an insulating insert 3.

On the cantilever part of the frame 1, two vacuum circuit breakers 4 and 5 are connected in series. The first switch 4 is installed with the possibility of connecting its pole via a conductive bus 6 and the cable 7 to the support body 2. The second switch 5 is installed with the possibility of connecting its pole to the contact network using loop 8.

A current transformer 9 and an active-capacitive voltage divider 10 are mounted on the conductive bus 6, which controls the voltage relative to the remote earth using wire 11.

The current transformer 9 and the voltage divider 10 are electrically connected to the emergency process recorder 12. The latter is equipped with an uninterruptible power supply 13. Both of these devices are installed on the site 14, by means of a conductor 15 electrically connected to the conductive bus 6. The site 14 is mounted on a supporting insulator 16 mounted on frame 1.

For remote control of switches 4 and 5, the device is equipped with a control unit 17 attached to the console part of the frame 1 with a radio signal receiver (not indicated) and an uninterruptible power supply 18.

The device operates as follows.

In preparation for operation, the device, delivered in an unassembled form to the test site, for example, by road, is mounted on a support 2 at a given point in the contact network. To do this, a collapsible metal frame 1 is attached to the support 2, on the console part of which the switches 4 and 5, the control unit 17 and the uninterruptible power supply are fixed 18. An insulator 16 with a platform 14 is fixed on the supporting part of the frame 1, on which the emergency process recorder 12 s is placed uninterruptible power supply 13. A conductive bus 6 with a current transformer 9 and a voltage divider 10 mounted on it is connected at one end to the pole of the switch 4. The other end of the bus 6 is connected by a conductor 15 to the platform 14 and with the help of eyfa 7 - a support body 2. The voltage divider 10, a wire 11 is connected to the remote ground. An electrical network is assembled for transmitting signals from a current transformer 9 and a voltage divider 10 to the measuring inputs of the emergency processes recorder 12. In the technological "window", the pole of the second switch 5 is connected to the contact network using a loop 8.

After the installation of the device is completed, the operator sends a radio signal to the control unit 17 to turn on the switches 4 and 5. In this case, the potential from the contact network through the cable 8, bus 6 and cable 7 is supplied to the support body 2 and a short-circuit current flows through the circuit. In order to avoid damage to the support in case of failure of the protections under study at the feeders of the traction substation or / and the sectioning station, the control unit 17, after a set time delay (about 4 seconds), sends a command to turn off switches 4 and 5.

When the current or voltage exceeds the preset value, the emergency process recorder 12 is automatically turned on, at the moment of closure it is under the potential of the contact network, and the waveforms of the values of currents and voltages of transients at the point of short circuit from the current transformer 9 and voltage divider 10 are recorded.

Claims (5)

1. A device for testing the protection of the AC contact network during a short circuit to the supports disconnected from the rails, including equipment for measuring current, voltage and recording of emergency processes, switches installed between the contact network and the ground electrode to reproduce the short circuit mode on the supports of the contact network, characterized in that it contains a frame made of two electrically isolated parts of one another, fixed to a support of the contact network, and a control unit for the switches, at the equipment for recording emergency processes is located on a site fixed on one part of the frame and electrically isolated from it, the switches and the control unit are located on the other part of the frame, the equipment for measuring current and voltage is mounted on a conductive bus, one end of which is connected to the first switch, and the other end is electrically connected to the support body of the contact network and equipment for recording emergency processes, the second switch is connected to the contact network by a loop. 2. The device according to claim 1, characterized in that the apparatus for measuring voltage is made in the form of a voltage divider. 3. The device according to claim 1, characterized in that the emergency process recorder is equipped with an uninterruptible power supply. 4. The device according to claim 1, characterized in that the control unit of the switches is equipped with an uninterruptible power supply. 5. The device according to claim 1, characterized in that the control unit comprises a radio signal receiver.