JPH0688512B2 - DC power supply - Google Patents

Description

The present invention relates to a power feeding device for an electric railway, and more particularly to a power feeding device for a DC electric railway that converts AC power into DC power and supplies the DC power as a drive source for an electric vehicle. Regarding

B. SUMMARY OF THE INVENTION The present invention is a power supply device for a DC type electric railway, in which two sets of a diode bridge circuit and a circuit breaker are combined,
Even if one of the circuit breakers fails, the train line connected to the broken circuit breaker is powered from the other circuit breaker, which makes it possible to significantly improve the system reliability. It is a thing.

C. Conventional Technology Conventionally, a DC substation installed along a railway line at appropriate intervals is provided with one or several sets of converters. The DC output side of each converter is connected to a DC high-speed circuit breaker dedicated to the converter, and the AC input side of the converter is connected to a common bus conductor. That is, the power feeding system including the forward power converter and the DC high-speed circuit breaker is connected in parallel between the substations to form a DC power supply for the DC substation.

On the other hand, train lines are generally divided between adjacent substations and by line, and the divided train lines are connected to each positive busbar at each substation through a DC high-speed circuit breaker dedicated to each line, and rails are Connected to the negative bus.

In general, adjacent substations are configured as power supply circuits for supplying electric power in parallel to the sectioned train lines.

FIG. 2 shows a conventional power supply device, 1 is a forward power converter including a thyristor control element for converting AC power into DC power, 2
Is an inverse power converter including a thyristor control element for converting DC power into AC power. 7 is a DC bus, 4a to 4d are power running thyristor circuit breakers (hereinafter referred to as power running circuit breakers), 5a
~ 5d is a regenerative diode, the anode side of these diodes 5a ~ 5d is connected to the cathode of the power running circuit breakers 4a ~ 4d, and the cathode side of the diodes 5a ~ 5d are collectively connected so that the regenerative thyristor circuit breaker 6 ( It is connected to the anode of a circuit breaker for regeneration hereinafter). The cathode of the regenerative breaker 6 is connected to the DC bus 7. The reverse power converter 2 is connected to the DC bus 7. 8a to 8d are DC disconnectors, 9a, 9b and 1
0a and 10b are the first, second and third and fourth train lines for up and down, which are divided by the dead section 11 and 12, respectively.

Next, the operation of FIG. 2 will be described. First, the electric power for power running of an electric vehicle is converted into an appropriate voltage by a transformer (not shown) from a three-phase AC voltage received from an AC circuit breaker (not shown) from a commercial frequency power source bus bar (not shown) at a substation, It is converted into DC power by the forward power converter 1 and supplied to the divided first and second train lines 9a and 9b and the third and fourth train lines 10a and 10b. The electric car 13 on the fourth train track 10b is powered by the DC power supplied as described above.

Next, when the electric vehicle 13 is in the regenerative operation, the regenerative power is the fourth
It is supplied to the DC bus 7 from the train line 10b through the regenerative diode 5d and the regenerative breaker 6. The regenerative electric power supplied to the bus bar 7 is driving a power running electric vehicle (not shown). For example, it is regenerated to the first train line 9a to the third train line 10a, or is regenerated to the power bus through the reverse power converter 2.

D. Problems to be Solved by the Invention (1) In the conventional example configured as shown in FIG. 2, the forward power converter 1 and the reverse power converter 2 are directly connected in antiparallel via the DC bus 3. Therefore, when the commutation of the reverse power converter 2 fails, there is a problem that a fault current is supplied from the forward power converter 1 side and the fault is expanded.

(2) In FIG. 2, if the regenerative breaker 6 is cut off, the following problems occur.

(A) When extension feeding is attempted to stop the feeding of only a desired feeding section, the feeding of the other adjacent train line is also stopped, which hinders the operation of the electric vehicle.

(B) If an attempt is made to cut off the regenerative current and the extension power supply current that flow from the train track at the time of an accident using only the regenerative breaker 6,
The breaking capacity of the circuit breaker 6 is required to be at least four times as large as that of the power running circuit breaker, assuming that the DC circuit in which the power running circuit breakers 4a to 4d are inserted is four circuits (in the case of double lines).

(C) In order to reduce the breaking capacity of the regenerative circuit breaker 6, if the capacity is such that the regenerative current can be cut off, if there is a regenerative vehicle at the time of an accident, the regenerative breaker 6 cannot cut off the extended power supply current. For this reason, the current flowing out to the accident point side must be interrupted at the adjacent substation side, the protection sequence at the time of an accident becomes complicated, and the reliability of the system deteriorates.

(D) In the case of four electric lines as described above, the power running circuit breakers 4a to 4d are inserted in each DC electric line, which makes the substation extremely uneconomical.

(E) In addition, since the substation equipment will be large, the equipment cost for construction will be enormous.

E. Means for Solving Problems This invention relates to a forward power converter for converting AC power into DC power, a power running busbar connected to the forward power converter, and a power running busbar connected in common. The cathode side is connected 2
Two sets of diode bridge circuits and two sets respectively provided in the two sets of diode bridge circuits and connected between the commonly connected anode side and the cathode side connected to the power running bus of these bridge circuits. Of the circuit breaker and the cathodes and the anodes of the diodes constituting the respective sides of the two sets of diode bridge circuits are separately connected to each other and are divided by a dead section forming a double line. , The second, third, and fourth train lines and the anode side of each of the two sets of diode bridge circuits connected in common, and normally open, and one set of the circuit breaker fails. It is composed of a DC disconnecting switch that is closed.

F. Operation As described above, even when only one of the two circuit breakers is cut off during extended power supply and only the desired feeding section is stopped feeding, the other circuit breaker is in the conducting state. You can continue the extension power supply of the train line. In addition, since the two commonly connected anode sides of the diode bridge circuits are connected to each other by a DC disconnecting switch, a mutual standby system is used in which power is mutually exchanged between the two diode bridge circuits. If the equipment breaks down, the entire circuit can be powered through the other circuit breaker. In addition to the above, the extended power supply current at the time of an accident is interrupted by a circuit breaker connected to the fault line, so that there is no need to cut off at an adjacent substation that supplies the extended power supply current.

G. Embodiment FIG. 1 is a circuit diagram showing an embodiment of the present invention. The same parts as those in FIG.

In FIG. 1, reference numerals 21 and 41 are first and second diode bridge circuits composed of four diodes 22a to 22d and 42a to 42d arranged in the illustrated polarities. The cathode sides of the diodes 22a, 22c and 42a, 42c in the first and second diode bridge circuits 21 and 41 are connected to the power running bus bar 3. 23 and 43 are first and second thyristor circuit breakers (this circuit breaker may be a DC high speed circuit breaker),
The anode sides of the first and second thyristor circuit breakers 23 and 43 are on the power running bus 3, that is, the diodes 22a, 22c and 42a, 42c.
Are connected to points 24 and 44 to which the cathodes of are commonly connected. The cathode sides of the first and second thyristor circuit breakers 23 and 43 are connected to points 25 and 45 to which the anodes of the diodes 22b, 22d and 42b, 42d are commonly connected.

The common connection points 26 and 46 of the diodes 22a and 22b and 42a and 42b of the first and second diode bridge circuits 21 and 41 are connected to the first and second train lines 9a and 10a via the DC disconnectors 8a and 8c. Connected. Also, the diodes 22c and 22d and 42c and 4 of the first and second diode bridge circuits 21 and 41 are
The common connection points 27 and 47 of 2d are connected to the second and fourth train lines 9b and 10b via DC disconnectors 8b and 8d.

The points 25 and 45, which are commonly connected to the two sets of diode bridge circuits 21 and 41, are connected by a mutual auxiliary bus 28, and a DC disconnector 29 is inserted in the electric path of the mutual auxiliary bus 28. This DC disconnector 29 is normally open and will be closed when either of the first and second thyristor circuit breakers 23 and 43 fails. Although the forward power converter is a diode rectifier, it may be a thyristor rectifier.

Next, the operation of the above embodiment will be described.

If the thyristor circuit breakers 23 and 43 are normally closed,
The power running current of the forward power converter 1 is the thyristor circuit breaker 23,43 →
Diodes 22b, 42b → 1st, 3rd via DC disconnectors 8a, 8c
The thyristor circuit breaker is supplied to the train tracks 9a and 10a.
23, 43 → Diodes 22d, 42d → Supplied to the second and fourth train lines 9b, 10b through the DC disconnectors 8b, 8d.

In addition, the regenerative current generated in the first train line 9a is a DC disconnector.
8a → diode 22a → thyristor cutoff path 23 → diode 2
2d → is supplied to the second train line 9b via the DC disconnector 8b, or the diode 22a → power running bus 3 → thyristor breaker 4
3 → Diode 42d → Supplied to the third or fourth train line 10a, 10b via the DC disconnecting switch 8c or 8d. The regenerative current generated in the second, third and fourth train lines 9b, 10a and 10b also flows through the first and second diode bridge circuits 21 and 41 and is supplied to each train line.

As described above, when the power running current is supplied to each train line 9a, 9b and 10a, 10b, two sets of first and second thyristor circuit breakers 23, 43 are provided.
Since it can be controlled only by inserting the two, there is an advantage that two sets of expensive thyristor circuit breakers can be omitted as compared with those in FIG.
As a result, the power supply device can be manufactured at low cost. Further, the regenerative current generated in each train line 9a, 9b and 10a, 10b can be similarly controlled.

Further, both the power running current and the regenerative current pass through the first and second thyristor circuit breakers 23, 43. Therefore, if the circuit breakers 23, 43 are opened, both power running and regenerative currents are blocked. Since it can be performed by the thyristor circuit breakers 23 and 43, the protection sequence can be simplified. By using the thyristor circuit breaker having the function of interrupting both power running and regenerative currents, for example, when a ground fault occurs at point F of the first train line 9a in FIG. If opened, the powering current is cut off. After that, DC disconnector 8a
Is opened and the thyristor circuit breaker 23 is closed again, the regenerative current is supplied to the third and fourth train lines 10a, 10b as described above even if the regenerative electric vehicle 14 is operating on the second train line 9b. To be done.

The first and second diode bridge circuits 21, 41 and the first, second
When extension power feeding using the thyristor circuit breakers 23, 43 is performed, only the first thyristor circuit breaker 23 is opened if only the desired feeder section (first and second train lines 9a, 9b) is stopped. Therefore, the extension power supply can be continued in the feeding section on the side of the third and fourth train lines 10a, 10b, and the electric vehicle can be smoothly driven.

If an accident occurs during the above-mentioned extended power supply, the thyristor circuit breaker 23 or 43 connected to the accident circuit cuts off the line, so it is not necessary to cut off at the adjacent substation that supplies the extended power supply current. Therefore, the protection sequence can be further simplified, the influence of the accident can be minimized, and the operation efficiency of the electric vehicle can be improved.

Further, in the above embodiment, if the DC disconnector 29 inserted in the mutual auxiliary bus 28 is closed, for example, when the first thyristor circuit breaker 23 fails, it will be connected to the first thyristor circuit breaker 23. Power can be supplied to the existing first and second train lines 9a and 9b from the second thyristor circuit breaker 43 side via the mutual auxiliary bus 28. This can improve the reliability of the system itself.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 3 shows an embodiment in which the present invention is applied to a power supply device of a direction-specific feeder system (a system in which a plurality of train lines are divided into one side and the other side and is fed to each direction). 3 is different from FIG. 1 in that the common connection point 27 of the diodes 22c and 22d is connected to the third train line 10a via the DC disconnector 8b, and the common connection point of the diodes 42a and 42b. 46 is a DC disconnector 8c
Is connected to the second train track 9b via
The other parts are configured the same as in FIG. In FIG. 3, when the thyristor circuit breakers 23, 43 are normally closed as in the case of FIG. 1, the power running current of the forward power converter 1 is such that the thyristor circuit breakers 23, 43 → diodes 22b, 43b → DC It is supplied to the first and second train lines 9a and 9b via the disconnectors 8a and 8c, and the thyristor circuit breakers 23 and 43 → diodes 22d and 42d → the third and fourth trains via the DC disconnectors 8b and 8d. It is supplied to the lines 10a and 10b.

Further, the regenerative current generated in the first train line 9a is also transferred to the third train line 10a via the DC disconnector 8a → diode 22a → thyristor circuit breaker 23 → diode 22d → DC disconnector 8b as in the case of Fig. 1. It is supplied or is supplied to the second or fourth train lines 9b, 10b via the diode 22a → powering bus 3 → thyristor breaker 43 → diode 42b or 42d → DC disconnector 8c or 8d. In addition, the second, third and fourth train tracks 9b, 10a and 10b
Similarly, the regenerative current generated in the same flows through the first and second diode bridge circuits 21 and 41 and is supplied to each train line.

As in the case of FIG. 1, the power supply current and the regenerative current can be controlled only by inserting the two sets of the first and second thyristor circuit breakers 23 and 43, as in the case of FIG. Therefore, there is an advantage that three sets of expensive thyristor circuit breakers can be omitted as compared with those in FIG. As a result, the power supply device can be manufactured at low cost. Further, since both the power running and the regenerative current can be interrupted by the two sets of thyristor circuit breakers 23 and 43, the protection sequence can be simplified. By using the thyristor circuit breaker having the function of interrupting both power running and regenerative currents as described above, for example, the first train track of FIG.
When a ground fault occurs at point F of 9a, the thyristor circuit breaker
If 23 is opened, the powering current is cut off. After that, if the DC disconnector 8a is opened and the thyristor circuit breaker 23 is closed again, the second, third, and fourth train lines 9b, 10a, and 10b are not affected by the ground fault, and the current is not affected. Supplied. Further, the first and second diode bridge circuits 21, 41 and the first and second diode bridge circuits 21, 41
When extension power feeding using the thyristor circuit breakers 23, 43 is performed, when only the desired feeding section (for example, the first and third train lines 9a, 10a) is stopped feeding, simply open the first thyristor circuit breaker 23. Therefore, the extension power supply can be continued in the feeder section on the second and fourth train lines 9b, 10b side, and the smooth operation of the electric vehicle becomes possible.

If an accident occurs during the above-mentioned extended power supply, the thyristor circuit breaker 23 or 43 connected to the accident circuit cuts off the line, so it is not necessary to cut off at the adjacent substation that supplies the extended power supply current. Therefore, the protection sequence can be further simplified, the influence of the accident can be minimized, and the operation efficiency of the electric vehicle can be improved.

Further, in the above embodiment, if the DC disconnecting switch 29 inserted in the mutual auxiliary bus 28 is closed, for example, when the first thyristor circuit breaker 23 fails, it will be connected to the first thyristor circuit breaker 23. It is possible to supply power to the existing first and third train lines 9a and 10a from the second thyristor breaker 43 side via the mutual auxiliary bus 28. This can improve the reliability of the system itself.

H. Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

a. Even when only the desired feeding section is stopped during extension feeding, the extension feeding can be continued in the feeding section on the other train line side, and the electric vehicle can be smoothly operated.

b. In case of an accident during extension power supply, the extension power supply current is cut off by the breaker connected to the fault line, so there is no need to cut off at the adjacent substation that supplies the extension power supply current. Therefore, the protection sequence can be further simplified, the influence of the accident can be minimized, and the operation efficiency of the electric vehicle can be improved.

c. Even if one of the two circuit breakers fails, the mutual protection method is used, so even for the train line connected to the broken circuit breaker side, The power can be supplied through the mutual reserve buses, and the reliability of the system itself can be improved.

g. Compared with the conventional example, since the regenerative breaker and the two sets of power running breakers are unnecessary, the facility cost is very advantageous. Further, since the circuit breaker is not required, the protection sequence is simplified and the reliability is improved.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a circuit diagram showing a conventional example, and FIG. 3 is a circuit diagram showing another embodiment of the present invention. 1 ... Forward power converter, 3 ... Power running bus, 9a, 9b, 10a, 10
b …… 1st to 4th train lines, 21,41 …… First and second diode bridge circuits, 23,43 …… First and second thyristor circuit breakers, 28 …… Mutual backup bus, 29 …… DC disconnector.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Hiroyasu Sato 2-17 Osaki, Shinagawa-ku, Tokyo Inside the Meidensha Co., Ltd. (56) Reference JP-A-60-176832 (JP, A)

Claims (1)

[Claims] 1. A forward power converter for converting AC power into DC power, a power running bus connected to this forward power converter, and two sets of cathode side connected in common to this power running bus. A diode bridge circuit and two sets of cutoffs provided separately for the two sets of diode bridge circuits and connected between the commonly connected anode side and the cathode side connected to the power running bus of these bridge circuits. And the above 2
First, second, and third sections, each of which is connected to a common connection point of cathodes and anodes of diodes constituting each side of a set of diode bridge circuits and which is divided by a plurality of dead sections, It is connected between the fourth train line and each commonly connected anode side of the two sets of diode bridge circuits, and is normally open and closed when one set of the circuit breaker fails. A DC power supply device comprising a DC disconnector.