Track circuit power supply vital monitor
View Patent ↗A power supply vital monitor for track circuits for railway systems includes a track segment that is separated from adjacent segments by electric joints. Each track segment includes a signal transmitting unit and receiving units for transmitting and receiving train presence detection signals and/or transmitting or receiving communication signals between the train and the track segment. The transmitting unit and receiving units are connected to a common power supply line. To avoid an erroneous clearing of an occupied status caused by spurious signals on the power supply line affecting reception of the train detection signals, each receiving unit includes a first and a second channel, which connect the receiver with the corresponding track circuit and with a power supply sensor connected to the power supply line. Switches enable and disable connections of the receivers to the corresponding track circuit and to the corresponding power supply sensor.
1. A track circuit comprising:
a power supply vital monitor adapted to monitor a power supply signal of railway systems;
a plurality of track segments ( 11 , 12 ) of predetermined length, forming continuous rails, and electric joints ( 2 ), each consisting of a conductor, which connects together the rails ( 111 , 112 ) at ends of each track segments; and
electric signal transmitting units ( 3 ) and receiving units ( 4 ) operatively coupled to each track segment ( 11 , 12 ) and adapted to receive and transmit train presence detection signals within each track segments and/or transmit communication signals between a train ( 7 ) and the track segments ( 11 , 12 ), each transmitting unit ( 3 ) and each receiving unit ( 4 ) being connected to a common power supply line ( 5 ),
wherein:
each receiving unit ( 4 ) comprises at least two parallel signal processing channels, which include a first ( 41 ) and a second ( 42 ) channel, each channel ( 41 , 42 ) comprising a receiver ( 411 , 421 ) connected to the track circuit and to a respective power supply sensor ( 412 , 422 ) connected to a common power supply line ( 5 ) through communication lines,
each single communication line connecting the receiver with both the track circuit and the respective power supply sensor,
each communication line having a first enabling/disabling device ( 413 , 423 ) in order to enable/disable a connection of the said receiver ( 411 , 421 ) with the corresponding track circuit, and a second enabling/disabling device ( 414 , 424 ) in order to enable/disable the connection of the said receiver ( 411 , 421 ) with the power supply sensor ( 412 , 422 ), and
the receivers ( 411 , 421 ) being connected to an analyzing unit ( 44 ), which analyzes output signals of the said receivers ( 411 , 421 ).
2. The track circuit according to claim 1 , wherein each receiving unit comprises a timing device ( 34 ), which activates the first and second enabling/disabling devices ( 413 , 414 , 423 , 424 ) of each communication line according to predetermined timing rules.
3. The track circuit according to claim 2 , wherein the timing device ( 43 ) comprises a processor means for executing a logical program, wherein execution of said logical program causes said first and said second enabling/disabling devices ( 413 , 414 , 423 , 424 ) to operate in such a way that activation of the first enabling/disabling device ( 413 ) of the first channel ( 41 ) deactivates the second enabling/disabling device ( 414 ) of the first channel ( 41 ) and the first enabling/disabling device ( 423 ) of the second channel ( 42 ) and activate the second enabling/disabling device ( 424 ) of the second channel ( 42 ), and vice versa.
4. The track circuit according to claim 1 , further comprising a system that sets the track circuit in a safety-condition.
5. The track circuit according to claim 1 , wherein the power supply sensor ( 412 , 422 ) comprises an analyzing system that compares a power supply signal with characteristic parameters uniquely identifying the train presence detection signals.
6. The track circuit according to claim 1 , wherein the receiver ( 411 , 421 ) has a processing and control section configured as a 2oo2 architecture.
7. A method to evaluate failure of power supply in a track circuit for railway systems or the like, wherein the track circuit comprises:
a plurality of track segment ( 11 , 12 ) of predetermined length, forming continuous rails, and electric joints, each consisting of a conductor, which connects together the rails ( 111 , 112 ) at ends of each track segments, and
electric signal transmitting units ( 3 ) and receiving units operatively coupled with each track segment ( 11 , 12 ) for transmitting and receiving train presence detection signals within each track segments and/or transmitting or receiving communication signals between a train ( 7 ) and the track segments, each transmitting unit ( 3 ) and each receiving unit ( 4 ) being connected to a common power supply line ( 5 ),
the method comprising:
a) analyzing the signals received by the receiving units ( 4 ) through two processing channels, each receiving unit ( 4 ) comprising at least two parallel signal processing channels ( 41 , 42 ), which include a first and a second channel, each processing channel comprising a receiver ( 411 , 421 ) connected to the track circuit and to a respective power supply sensor ( 412 , 422 ) connected to the common power supply line ( 5 ), through communication lines,
each single communication line connecting the receiver with both the track circuit and the respective power supply sensor,
each communication line having a first enabling/disabling device ( 413 , 423 ) adapted to enable/disable a connection of the said receiver ( 411 , 421 ) with the corresponding track circuit and a second enabling/disabling device ( 414 , 424 ) adapted to enable/disable the connection of the said receiver ( 411 , 421 ) with the power supply sensor ( 412 , 422 );
b) connecting the receiver ( 411 , 421 ) belonging to the first signal processing channel ( 41 ) to the track circuit and disconnecting the receiver ( 411 , 421 ) belonging to the first signal processing channel ( 41 ) to the power supply sensor, disconnecting the receiver ( 411 , 421 ) belonging to the second signal processing channel ( 42 ) to the track circuit and connecting the receiver ( 411 , 421 ) belonging to the second signal processing channel ( 42 ) to the power supply sensor ( 412 , 422 );
c) analyzing output signals of said receivers ( 411 , 421 ) through an analyzing unit ( 44 ); and
d) setting a status of the track segment ( 11 ) according to the output signal of the analyzing unit ( 44 ).
8. The method according to claim 7 , wherein step b) is achieved by activating the first enabling/disabling device ( 413 ) belonging to the first processing channel ( 41 ) and the second enabling/disabling device ( 424 ) belonging to the second processing channel ( 42 ) and deactivating the second enabling/disabling device ( 414 ) belonging to the first processing channel ( 41 ) and the first enabling/disabling device ( 423 ) belonging to the second processing channel ( 42 ).
9. The method according to claim 8 , wherein the activating/deactivating of the first and of the second enabling/disabling devices is achieved according to predetermined timing rules,
each receiving unit comprising a timing device ( 43 ) which activates/deactivates the first and second enabling/disabling devices ( 413 , 414 , 423 , 424 ).