Abstract:
A power supply system for a long-stator drive having at least two independent tracks, which each have at least one long-stator section and which can be connected to one another using at least one track-changing device, the long-stator sections being split into a plurality of drive regions, using which each vehicle can be independently driven, and at least one track-changing device having at least one electrical contact which is positively guided by the track-changing device in such a manner that an electrical connection can be produced or eliminated between various long-stator sections.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a power supply system for a long-stator drive. 
     BACKGROUND INFORMATION 
     A conventional power supply system is described, for example, in German Patent No. 28 05 994. The conventional power supply system has two mutually independent tracks, each having a long-stator winding. The winding sections of each track can be connected to the substations via two parallel power cables and switching devices. The switching devices include non-contacting semiconductor switches and contacting switching elements. The contacting switching element is closed by the corresponding semiconductor switch before the voltage is connected, while in contrast the contacting switching element is opened by the semiconductor switch after the voltage has been disconnected. 
     Furthermore, “Energieversorgund des Langstatorantriebs” Supplying Power to a Long-Stator Drive), J. Meins, “etz”, Vol. 108, No. 9, 1987, pp. 378-81 describes a conventional power supply system for a long-stator drive. This power supply system includes a track having a left and a right motor side. A plurality of long-stator sections are combined to form at least one drive region. Each drive region is characterized in that all its stator sections are supplied with power by the same converter. The limits for the drive regions are generally chosen such that these limits are at the preselected interval between trains, so that a plurality of vehicles may travel at the same time interval on the single track. 
     In addition, for a track having a long stator, a track-changing device, designed as a switch, is described in “Stand der Entwicklung des elektromagnetischen Schnellbahnsystems” (Development Status of the Electromagnetic High-Speed Railway System), Von Rudolf Zurek, ZEV-Glas. Ann., Vol. 104, Nos. 8-9, August-September 1980, pp. 233-40. The relevant switching section ends at the moving end of the switch. 
     In addition, French Patent No. 2,688,523 describes a track-changing device for two independent tracks of a long-stator drive. The track-changing device is designed as a switch and the two independent tracks each have at least one long-stator segment. 
     Finally, German Patent No. 25 44 665 describes a mechanically regulatable switch for a magnetic overhead railway. The switch includes a movable tongue, on which a stator winding of a linear motor and secondary conductor loops, situated beneath, are arranged. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to simplify supplying power to a long-stator section. The relevant switching section ends at the moving end of the switch. 
     In addition, French Patent 2,688,523 A1 discloses a track-changing device for two independent tracks of a long-stator drive. The track-changing device is designed as a switch and the two independent tracks each have at least one long-stator segment. 
     The object of the present invention, in the case of a power supply system for a long-stator drive, is to make it simple to supply power to a long-stator section which is routed via at least one track-changing device. 
     The power supply system according to the present invention for a long-stator drive includes at least two independent tracks which each have at least one long-stator section and which can be connected to one another using at least one track-changing device. The long-stator sections are split into a plurality of drive regions, by means of which each vehicle can be independently driven. At least one track-changing device has at least one electrical contact which is positively guided by the track-changing device in such a manner that an electrical connection can be produced or eliminated between various long-stator sections. 
     In the case of a power supply system, at least one long-stator section is connected to one drive region or the other. The limits of the drive regions can therefore be set as required. The track or parts of it can thus be assigned to different drive regions as a function of the position of the track-changing device or devices. The time during which the drive regions are occupied can thus be adjusted in a simple manner. 
     Reliable disconnection of the relevant long-stator section is necessary, for example, if the vehicle is moving towards an open switch end, under conditions of a fault having occurred. The switches would therefore have to be monitored continuously for correct operation by very expensive monitoring devices in the highest safety category. In the event of a fault, i.e., in the event of the failure of the monitoring device or failure of the switching devices, all the drive regions which could be supplied on the relevant track region must be disconnected from the power supply system. This generally results in a serious operational disturbance. 
     The cabling cost for a power supply system according to an exemplary embodiment of the present invention is particularly low, whereas, in contrast, a power supply system according to another exemplary embodiment of the present invention allows large drive regions to be reconfigured. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     FIG. 1 shows a section having two parallel-running tracks in normal operation. 
     FIG. 2 shows the section according to FIG. 1 with a fault in one drive region. 
     FIG. 3 shows the section according to FIG. 2 with a fault in another drive region. 
     FIG. 4 shows an electrical contact, which is particularly suitable for the power supply system according to the present invention, in the open position. 
     FIG. 5 shows the electrical contact according to FIG. 4 in one of its closed positions. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1-3 show a first track  1  and a second track  2 . Two tracks  1  and  2  can be connected to one another using two transfer points  3  and  4 . 
     In the illustrated exemplary embodiment, transfer point  3  includes two switches  5  and  6  as well as a rigid track part  7 . Analogously, transfer point  4  includes two switches  8  and  9  as well as a rigid track part  10 . 
     FIGS. 1 to  3  illustrate four drive regions. In normal operation (FIG.  1 ), drive regions  11  and  12  are assigned to track  1 , and drive regions  13  and  14  to track  2 . 
     In FIGS. 1 to  3 , drive region  11  is shaded diagonally, drive region  12  is dotted, drive region  13  is shaded vertically, and drive region  14  is shaded by crossed lines. 
     Drive regions  11  and  12  have a common drive region limit  15 , and drive regions  13  and  14  have a common drive region limit  16 . The train sequence is governed by drive region limits  15  and  16 . 
     In order to make it possible to change quickly from track  1  to track  2 , transfer points  3  and  4  should be arranged as close as possible to drive region limits  15  and  16 . Direct arrangement at track region limits  15  and  16  is generally not possible, for routing reasons. Drive regions  11  to  14  are supplied in a conventional manner via section cables  17  to  20 , from drive blocks  21  to  24 . 
     Each switch  5  and  6  as well as  8  and  9  is assigned, in each case, two contacts  25  to  32 . Contacts  25  and  26  are, in this context, positively guided by switch  5 , contacts  27  and  28  by switch  6 , contacts  29  and  30  by switch  8 , and contacts  31  and  32  by switch  9 . 
     The position of the switch thus governs the track with which contact is made. Rigid track part  7  of transfer point  3  has two mating contacts  33  and  34 . Rigid track part  10  of transfer point  4  has two mating contacts  35  and  36 . 
     Furthermore, track  1  has mating contacts  37  and  38  in the region of switches  5  and  8 . Track  2  has mating contacts  39  and  40  in the region of switches  6  and  9 . 
     In normal operation (FIG.  1 ), tracks  1  and  2  are separated from one another, drive region  11  being connected to section cable  17  via a closed supply switch  41 , and drive region  14  being connected to section cable  20  via a closed supply switch  42 . In normal operation, contact  25  of switch  5  makes contact with mating contact  37  of track  1 , and contact  29  of switch  8  makes contact with mating contact  38  of track  1 . In the same way, contact  27  of switch  6  makes contact with mating contact  39  of track  2 , and contact  31  of switch  9  makes contact with mating contact  40  of track  2 . 
     If a fault occurs in drive region  12  (FIG.  2 ), then a connection is made between track  1  and track  2  by switching switches  5  and  6  of transfer point  3 . In consequence, drive region  11  extends directly to drive region  13 , although these drive regions do not adjoin one another in normal operation (FIG.  1 ). This means that, on the one hand, the occupancy time of drive region  11  is not significantly changed and, on the other hand, drive region  14  is not unnecessarily blocked (overoccupied) by the vehicle transferred from drive region  11  but rather the vehicle assigned to it can travel as before. Furthermore, in the event of a fault, it is always sufficient to disconnect the drive region (for example, drive region  11 ) which is assigned to the affected vehicle, since it is not possible for other drive regions (for example, drive region  14 ) to influence the affected vehicle, so that unnecessary disconnections of a plurality of drive regions are avoided. 
     In the event of a defective drive region  11 , those parts of the drive regions of track  1  and track  2  which are still intact are likewise connected to one another, in an analogous manner, by switching switches  8  and  9 . 
     FIGS. 4 and 5 show an exemplary embodiment of the design refinement of the contacts and mating contacts using the example of switch  5 , the track being supplied via switch  5 . 
     Contacts  25  and  26  are arranged on the lower side of switch  5  while, in contrast, mating contact  33  is arranged on rigid track part  7  of transfer point  3 , and mating contact  37  is connected to drive region  11 . Contacts  25  and  26  and mating contacts  33  and  37  are designed as having three phases, each phase of contacts  25  and  26  as well as each phase of mating contacts  33  and  37  being designed identically, and the three phases being arranged in parallel with one another. Contacts  25  and  26  form a three-position contact K, which allows there to be one open position and two closed positions. Contacts  25  and  26  have one contact element  50  for each phase, said contact element  50 , in each case, being routed in an electrically insulated guide  51 . 
     The three phases of contact  25  are each connected to the corresponding phases of contact  26  via, in each case, one connecting element  52 . Furthermore, the corresponding phases of contact  25  and the corresponding phases of contact  26  are electrically conductively connected to one another via, in each case, one electrical cable  53 , and are connected to the corresponding phase of the stator in switch  5 . 
     Furthermore, three contact elements  50  of each phase of contacts  25  and  26  can be moved back to the rest position, in each case, using one spring  54 . Springs  54  are thus unstressed when contacts  25  and  26  are in the open position (FIG. 4) and are stressed when contacts  25  and  26  are in the two closed positions (FIG.  5 ). 
     When three-position contact K is in the open position, three contact elements  50  of contact  25  and three contact elements  50  of contact  26  are in contact, in each case, with one short-circuiting bar  55 . Connecting elements  52  and springs  54  ensure that contact elements  50  of contacts  25  and  26  move synchronously. 
     Three-phase mating contacts  33  and  37  likewise each have a contact element  56 , which is likewise guided in an electrically insulated guide  57 . 
     When three-position contact K is opened, its structural design ensures that a three-phase short circuit occurs first through contact elements  50  contacting short-circuiting bar  55 , and three contact elements  50  of contact  26  are then disconnected from three contact elements  56  of mating contact  33 . This reliably prevents any arc from being formed between contact  26  and mating contact  33 .