LT3235B - Circuit arrangement for electric rectifing substation - Google Patents

Abstract

This invention involves the connection circuitry of an electric current rectification substation for electrified transport, where the substation is an electric current rectification centre which can be controlled, partially controlled or not controlled. According to this invention, the derivation of the line is supplied through the flash switch (13, 14). There is a pole on the derivation side, to which there is a connected structural connection group (6, 7), which leads through two stub lines (20, 21) into the commutative installation (9), consisting of the commutative thyristor (12), and at least one extinction circuit and the storage buses (3) of the conjunctive diodes of the direct current.If there is a central thyristor demi-block (1), it has an additional extinction installation (8).You can use connection circuitry for all rectification substations with the storage buses of the direct current.

Description

The present invention describes a circuit diagram for an electrified transport current rectifier substation where the substation is a center of current rectifier. The current ironing center can be controlled, partially controlled or unmanaged.

The current leveling substation, which is designed to supply DC lines, uses a series of jumpers on the line junctions, which can reliably disconnect when setting a certain On size in the event of a current overload or short circuit. Such switches are mechanical and relatively uneconomical and pose additional safety problems due to the spark between the switch contacts. Sparks cause faster wear on the switches, requiring frequent maintenance of the sudden switches.

According to EP-A-206150, direct current bus thyristors are known as switches. The ironing substation on the current path to the current ironing unit is equipped with an additional switch, which results in higher losses in the overall installation expense, requiring higher investment costs. In addition, additional valves must be used so that the station, ie. y. a back-up power supply for the braking energy feed back is provided through the current leveling substation.

Another solution with thyristors, switches on three-phase current busbars, designed to disconnect interfering line branches, is known from DD-A-261485.

Despite the requirement, in this case, to adjust the valves for braking power feedback, such a solution for disconnecting a defective section of the ironing substation is inappropriate because of the resulting short circuit continuity, e.g., over a period of 200 ms, the thyristor-switch arrangement results in irreversible losses.

It has been proposed to install the rectifier partially as a semi-thyristor block, which would result in a sudden cut-off through the extinguishing circuit, whereby a short-term, voltage-free sudden cut-off switches off the corresponding branch. This can continue the operation. Unfortunately, this always results in short breaks without voltage.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a circuit diagram for operating a current rectification substation used for supplying electrified transport current using a central rectifier unit and quick disconnectors which are economical on the one hand and safely disconnects short circuits and return currents control the line branching in a simple way.

The task according to the invention is solved by the following scheme:

Plus - the DC bus - the accumulator bus provides the necessary branching through the abrupt disconnector and current converter. The DC bus is in turn supplied by a central rectifier. It may be a controlled, partially controlled or unmanaged ironing unit. Each pole of the abrupt isolator has a structural connection group consisting of 2 non-parallel valves on the pole, preferably diodes leading to the ground line to which the switchgear is connected. It is connected to the plus pole of the central rectifier. (Reverse pole positions are also possible).

In the event that the rectifier is controlled, the extinguishing arrangement provided for the central ironing unit is connected to a three-phase current-accumulator bus.

Switchgear The apparatus preferably comprises a switching thyristor having at least one extinguishing reset.

The extinguishing branch is formed in a known manner, from a quenching thyristor and a quenching capacitor. At best, it is connected via a diode to a commutative thyristor.

A switching group may ideally consist of a single extinguishing device, provided that a separate switching thyristor is assigned to the emergency disconnector. A positive solution is when each current direction is provided with a commutation thyristor and a quench branch.

How the scheme works:

Constructively, having a rectifier as an ironing center, disconnects large short-circuit currents from the central current rectifying unit at a certain point in the defect while extinguishing the thyristor unit and using a quenching device.

Current flows from distant power points to the defect site through the switchgear and is disconnected in the extinguishing branch of the switchgear. In this way, overcurrent locking causes the emergency switch to open while preventing ignition pulses from entering the central ironing unit. The extinguishing thyristor of the extinguishing device is temporarily ignited, and then the commutation device of the switchgear is ignited according to the set ignition time, and after a certain constant time or after receiving a signal from the emergency switch, the switching extinguishing branch is disconnected.

Depending on the state of the art, the thyristor block can then be turned on again to continue feeding undefined sections. Thereafter, at any branch disconnection, a sudden disconnector is applied and the commutation thyristor is lit so that the current is rapidly transferred from the abrupt switch current line to the commutation thyristor. After a constant period of time, either the ignition of the commutation thyristor or the receipt of a signal from the abrupt switch disconnects the switching device extinguishing branch and, irrespective of the current direction, the electronic disconnection occurs through the abrupt disconnector.

In a design with an uncontrolled central rectifier, all line branching - and thus short-circuit - disconnection is disconnected based on the latter method. After disconnecting a particular line, the switching thyristor can be tested without the need for a special control impedance. With the existing extinguishing wheel, the control current can be deactivated and the inspected section switched back to the state of the art.

If a thyristor is applied to the return valves of the connecting structural valves, ideally both valves of the connecting structural valves are connected to a single ground line which functions as a free ground line and a return power ground line.

The construction of the subject matter of the invention is further explained in the definition.

The invention is illustrated by examples of construction.

The drawings show:

FIG. 1 is a connection diagram of an ironing substation according to the invention with a central partially controlled iron,

FIG. 2 is an arrangement diagram according to the invention adapted to an ironing substation with an uncontrolled central rectifier,

FIG. 3 is a diagram of FIG. Option 2 with additional standby extinguishing capability and

FIG. 4 - Option with only one grinding line.

Preference is given to an example of an ironing substation connection diagram with a partially controlled rectifier and this is schematically illustrated in FIG. 1.

The central rectifier consists of a thyristor half-block 1 and a diode half-block 2. It supplies, for example, plus-dc-accumulator bus 3. Plus dc-accumulator bus 3 has 2 line outputs 4 and 5 having one structural link group 6 and 7. According to this example, the connection of the line is realized in such a way that in the catenary, beside the ironing substation shown in the drawing, other ironing substations are also supplied, creating a continuous connection between the sections of the catenary not shown in the drawing. The ironing substation with the thyristor technique according to the invention includes a quenching device 8 and a switching device 9. The latter can perform the function of disconnecting the line and checking the line.

When branching fault 5 occurs, the following process is performed:

- blocking of thyristor half block 1, ignition of extinguishing thyristors 10 and 11, LT 3235 B

- actuation of emergency isolator 14,

- ignition of commutation thyristor 12, and

- for example, at constant distance, ignition of the extinguishing thyristor 15 and the switching device 9.

Closing the thyristor half-block 1 and igniting the extinguishing device 8 suddenly disconnects the high short-circuit current from the near ironing station. A sudden switch 14 is opened and the voltage drop in the opened isolator section is shortened by switching thyristor 12 so that the current from the rectifying stations below is not flowing through the switching diode 14, but via communication diode 17, RL - combination 67, ignited switching thyristor 12, communication line 18 entering the idle ground line 20 and from there, through the auxiliary disconnector 25 and through the idle diode 27, to the branch 5 defect site.

After any cut-off and ignition of the thyristor half-block 1, a section check can be carried out via the communication diode 17 and the switching thyristor 12, simultaneously disconnecting the control current through the extinguishing branch-extinguishing thyristor 15 or 31, extinguishing capacitor 35 or 36. In this case after which it is switched on again. Alternatively, with the branching off 5, the bipolar auxiliary disconnectors 24, 25 may be opened and the activation of the overhead branching branch 5 will be galvanically completely separated.

Normal branch cut-off is shown as an example of the reverse power cut-off. When the reverse current flows from branch 5 to branch-on 4, which must be switched off, the auxiliary switch 14 is triggered and the commutating thyristor 12 is triggered. The reverse current switches from the opening of the emergency switch 14 to the following circuit: feedback diode 29, auxiliary isolator 24, a return-to-ground line 21, a communication line 19, via a switched-on thyristor 12, an RL combination 66, and a communication diode 16 to the Plus-DC accumulator bus 3, where the loop is terminated by line-on 4 where the feedback power was to flow. Parallel to the communication diode 16, a portion of the feedback current flows through the communication line 18, the auxiliary disconnector 23, and the idle diode 26 to the line enable 4.

In a similar manner, the return current is disconnected via a sudden switch 13 in section 4 by switching to the return diode 28, the auxiliary disconnector 22, the feedback-ground line 21 and the switching thyristor 12.

Since the flow sequence is always the same, regardless of the current direction, it is not necessary to measure the current direction.

In order to create a simple reserve, the switching device 9 preferably has two extinguishing branches, whereby one extinguishing branch with the quenching capacitors 35, 36 always extinguishes the switching current through the switching thyristor 12, namely by switching on the respective quenching thyristor 15 or 31 at a constant 12 with respect to ignition.

The extinguishing capacitor 30 in the extinguishing device 8 is reloaded in a short time through the support branch 32, so that no reserve is needed in this case. Thyristor Half Block 1 Ideally Activated 6 ms after Closing. Vehicles on intact lines do not notice voltage drops.

Ideally, the idle diode 38 is used to create a connection between the rail (anode) and the section switching (cathode) to prevent overvoltage at the inductors in the event of sudden short-circuit currents being cut off.

The communication diode 37 guarantees a faultless switching of the defective current from the thyristor half-block 1 to the quench capacitor 30 and disconnects the support branch 32 from the Plus - DC current storage bus 3.

The use of a communication diode 39 provides a smooth switching of the cut-off current via the switching thyristor 12 to the quench capacitor 35 or 36 while disconnecting the support branch 32 which is electrically coupled to the quench capacitors 35, 36 via control line 40 switching thyristor 12.

The ironing substation according to FIG. 2 has a power center with Plus - DC - accumulator bus 3, from which the terminals 4 and 5 are connected. The terminals 4, 5 can be separated by a sudden switch 13, 14 from a DC - accumulator bus 3. one communication structural group 6, 7. The communication groups 6, 7 are comprised of idle diodes 26, 27 and anti-parallel return diodes 28, 29 thereof, the poles of which are located on the side of the emergency switch 13, 14. They lead via auxiliary separators 22, 23, 24, 25 to the idle ground line 20 or to the return power ground line 21, which in turn leads to the switching arrangement 47.

The switching arrangement 47 consists of at least two extinguishing branches, a primary extinguishing branch consisting of a quenching thyristor 15 and a quenching capacitor 35, and a quenching quadrant with quenching capacitor 41 and quenching thyristor 42 in the reverse direction.

The switching thyristors 43, 45 or 44, 46 in this example are connected in parallel to the sudden disconnectors 13, 14.

Disconnecting branch 4 or 5 causes opening of the respective emergency disconnector 13, 14, while igniting the respective switching thyristor 43, 44. The current switches from the opening of the emergency disconnector 13, 14 to the corresponding switching thyristor 43, 44. Over a period of time the contact of the emergency disconnector 13, 14, the quenching thyristor 15 is ignited and the current is switched off again via a commutation thyristor 43 or 44, via a first quench branch consisting of quenching thyristor 15 and quenching capacitor 35.

Thanks to the switching thyristors 43, 44 arranged in parallel to the sudden disconnectors 13, 14, a single line can be checked and, depending on the result obtained, the tested line branch 4, 5 can be switched on again.

Reverse current quenching, for example, when current flows from branching input 4 via Plus - DC bus 3 to input 5, proceeds in the same way, only via commutation thyristor 45, quenching thyristor 42 and quenching capacitor 41. In order to have ready quenching reserves in both currents extinguishing capacitor, both extinguishing branches are formed according to the embodiment shown in FIG. 3 such that the extinguishing capacitors 35, 41 are directed to the idle ground line 20 or the return power ground line 21, and the extinguishing capacitors 35, 41 are directed to these lines perpendicular to each other through thyristors 48 and 50 with Plus - DC - accumulation bus. 3, and the other capacitors are connected via thyristors 51, 49. The second quenching process uses a quenching capacitor 41, e.g., by firing the thyristors 50, 51 at the end of the quenching process with the quenching capacitor.

The cut-off section 4 is checked with a switching thyristor 43, which is also ignited when the current transformer receives current from the current transformer, and the quenching thyristor 15 is automatically ignited and the defective current is disconnected. If the current threshold is not exceeded, then after a timeout, for example, the emergency disconnector 13 is switched on again for about 3 s and the normal current section 4 is restored.

The drawing shows two ironing substations with current inputs la and lb, where the first ironing substation is explained more fully than the second. These substations are similar in structure and interconnected in such a way that the two-track line is gradually switched.

Another ironing substation may be configured and otherwise, e.g.

The ironing substation depicted consists of a Plus - DC current storage bus 3, from which line sections A, B, C and D are connected, shown in the drawing with the aid of: direct disconnectors 13, 14, current transformer 52, idle diodes 26, 27, return valves 28, 29, auxiliary disconnectors 23, 25. Auxiliary disconnectors 23, 25 are connected to a free-flowing line 20. Between Plus - DC-accumulator bus 3 and a free-flare line 20 is a switching arrangement. It consists of a commutation thyristor 12 and a quench branch consisting of a quench thyristor 15, a quench capacitor 35, and a communication diode 39.

Between the line earth (Minus-Polius) and the idle ground line 20 is a free-diode 38 connected.

Both anodes, namely the communication diode 39 and the idle diode 38, are connected via a support branch 32 consisting of an inductance and a resistance. Just as lines A to D and switchgear 9, the same elements of the second ironing substation are present in other substations.

Line sections 53, 54, 55, 56, 57 and 58 are connected to the following line branches: 53 with B, 54 with D and B2, 55 with D2, 56 with A, 57 with C and A2, 58 with C2. Also shown is a transverse connection to the switching device 59. The switching device 59 is activated in this case.

The mode of operation is explained by disabling defective sections when short circuit 60 occurs on line 54. Line branchings D and B are on and line branches A and C are off. The same applies to the second leveling substation and others, and the cut-off value is only achieved in line branches D and B2. Other line inputs can be triggered by di / dt - protection.

Disabling line branches D and B2 is described by the line branch

D an example of a shutdown. Line branch D abrupt separator 63 has a trip command; a switching thyristor 12 and a feedback thyristor (not shown in the drawing, analogous to 28 or 29) are energized to switch current from the opening of the sudden disconnect 63 to the switching thyristor 12, the idle-to-ground line 20, the auxiliary disconnect 61, and 62 to line branch D so that the short-circuit current to short-circuit 60 is supplied by the following path: from Plus DC to the storage bus 3 via commutative thyristor 12, through the free-to-ground line 20, the switch 61, the free-diode 62, and the line branches D Current Transformers 52.

The switching of line branch B2 using switching equipment of the second ironing substation is also treated 9.

After a constant time or upon contacting the opening of branch line D, the abrupt disconnector 63, the quenching thyristor 15, which receives the current of commutation thyristor 12 (negative potential of switching thyristor 12 due to capacitor output voltage), is ignited, replacing the quenching capacitor 35. terminates line branch D shutdown. When the extinguishing thyristor 15 is lit, a short pulse current flows through all communication branches (idle diodes and auxiliary disconnectors), and when the disconnectors are closed, in particular in this case the line input B is touched. The magnitude of this impulse current is limited by impedance 64. ., through line branching B elements, is completely avoided by replacing the idle diodes with thyristors and igniting only the thyristor whose line input must be turned on, in this example only the line branch D.

Support line 32 provides safe disconnection if the lines are idle. The idle diode 38 reduces the switching voltage.

If there is a short circuit 60 and at the same time or with a short time difference, the separation point between lines B and D is electrically connected. Now a current is flowing through the short circuit 60 which can reach such a level that B would open and re-ignite switching thyristor 12 and line B feedback thyristor 29, or, by way of example, a switching current would flow, then reset the quenching thyristor 31 and quenching capacitor 36 to completely disable the first ironing substation (as described), short circuit current.

The defect description is also pre-declared. All line segments A, B, C, D in the given example are enabled. It may be necessary to disable line branching B, C and D, or else branching A. All of the described schemes work as described. In the example it is shown that the defective current shown by the movement 65 occurs at an unfavorable time when a spare quenching thyristor 31 is required since the first quenching reset has already begun.

The feed-back currents, eg flowing through the opening of the abrupt disconnector 13 into line branch D, are connected as follows:

- Emergency disconnector 13 opening command,

- Ignition of the commutation thyristor 12, and at the same time ignition of line branch A feedback thyristor 28.

The current switches to the following line:

- line branching A feedback thyristor 28,

- auxiliary separator 23,

- free-running sanding line 20,

- a line-breaking D-free diode 62 to the line branch D.

The feedback thyristor 28 is not extinguished, but is automatically extinguished when the current reaches zero in the stop mode.

After a switch-off, a line can be checked through the switching thyristor 12, and the control current is switched off again via the quenching branch - quenching thyristor 15, quenching capacitor 35 and communication diode 39.

With the described wiring diagram, it is possible to disconnect them from the DC busbars irrespective of the fault current and the load current directions, for which only the line current values (absolute value) are required. The line is tested without line resistance, because of the built-in technical elements of the communication and extinguishing group.

Claims (12)

DEFINITION OF INVENTION 1. Connection diagram of a current rectifier substation with a direct current bus, to which several line branches are connected via a sudden disconnector, and a central rectifier unit, characterized in that each pole on the side of the line is connected to a rectifier (13,14,63). a communication structural group (6,7) fed to an idle ground line (20) and a feed back ground line (21) leading to a switching device (9) consisting of one or more switching thyristors (12) connected in parallel at least one extinguishing branch. 2. Connection diagram according to claim 1, characterized in that the central ironing unit is a controlled iron. 3. Connection diagram according to claim 1, characterized in that the central ironing unit is a non-controlled iron. 4. Connection diagram according to claims 1 and 2, characterized in that the central ironing unit is a partially controlled iron. 5. A circuit diagram according to claim 1, 2 or 4, characterized in that the thyristor block (1) of the central ironing unit is a separate extinguishing device. 6. A wiring diagram according to claim 1, characterized in that the switching thyristor (12) is connected to the Plus - direct current - collecting bus (3) via the connection diodes (16,17) and / or via an R-L combination on both sides. 7. A circuit diagram according to claim 1, characterized in that the communication structural group consists of a free-flowing valve, an anti-parallel return valve and corresponding auxiliary isolators (22,23,24,25). 8. Connection diagram according to Item 7, b e s i s k i - r i a n t i that free course valve is idle diode {26.27 , 62). 9. Connection diagram according to Item 7, b e s i s k i - r i a n t i that free gait valve is idle thyristor. 10.Wiring diagram according to Item 7, b e s i s k i - The fact is that the return diode is used as a return valve. 11. A circuit diagram according to claim 7, characterized in that the feedback thyristor (28,29) is used as a feedback valve. 12. The circuit diagram of claim 1, wherein the extinguishing branch comprises a quenching thyristor (15.31) and a quenching capacitor (35.36). 13. A circuit diagram according to claim 11, characterized in that the extinguishing branch or branches are connected via a communication diode (39) to a switching thyristor (12). 14. Wiring diagram according to claim 11, characterized in that the extinguishing branch or branches are connected to a minus line through a support branch (32) consisting of an ohmic resistance and an inductance. A circuit diagram according to claim 1, characterized in that a miniature line (20) is connected between the minus line and the stroke line (20).