A virtual marshaling full-state switching control system and method based on vehicle-to-vehicle communication

Abstract

The present invention discloses a virtual marshaling full-state switching control system and method based on vehicle-to-vehicle communication. The control method comprises the following steps: taking two trains as an example, the first train is the front train and the second train is the rear train; the multi-train control method is the same as that of the two trains; the state switching is performed according to the train operation status, communication status and position; the states include formation operation state, independent operation state, unexpected disassembly state and complete disassembly state; the present invention considers the whole process of train departure, marshaling and parking, considers the operation and braking of the train at stations and sections, comprehensively and in detail covers the tracking situations that may be encountered, ensures the operation safety of the train and improves the transportation efficiency; does not need to add too much equipment, only needs to increase vehicle-to-vehicle communication, greatly improves the equipment compatibility and reduces the consumption of time and economic costs.

Description

Technical Field

[0001] The present invention relates to the field of rail transportation technology, and in particular to a virtual marshaling full-state switching control system and method based on vehicle-to-vehicle communication. Background Art

[0002] With China's growing population and people's pursuit of a better life, demand for high-speed rail travel and freight is increasing annually. However, currently, fixed and quasi-moving block systems are the predominant blocking methods used on railways. While these largely ensure train safety, they sacrifice some capacity. Moving block systems, however, increase the speed of trains, leading to longer tracking distances between trains, hindering capacity expansion. Land and funding constraints have also hindered the construction of new lines, leading to the introduction of a new train control method: virtual marshaling. Virtual marshaling, as the name suggests, involves combining multiple trains using virtual "couplers" to form a long, closely spaced train-to-train train. The virtual coupler designates a relatively fixed safety distance between trains. In this tracking method, the following train not only monitors the rear position of the preceding train but also determines its following distance based on the preceding train's speed. This reduces the absolute braking distance required under moving block systems to a relative braking distance, significantly shortening the inter-train distance and thereby increasing railway capacity. Moreover, since it is freed from the physical constraints of coupling, multiple trains can be formed and disassembled more flexibly, thus better adapting to different passenger flows and line conditions and avoiding the waste of train resources.

[0003] Virtual marshaling can shorten the tracking distance between two trains and enable flexible formation and disassembly of multiple trains. This raises the corresponding issues of safe tracking control and the need for attention to the operational state transitions of virtual marshaling trains. Generally speaking, a train encounters multiple states during marshaling, which can be broadly categorized as independent operation, formation operation, unexpected disassembly, and complete disassembly. However, there is currently no detailed and comprehensive study on the timing of these state transitions, how these transitions are communicated, how these transitions are safely controlled, and the control issues associated with the operational state transitions and tracking processes encountered during virtual marshaling operations, from independent operation to formation preparation, formation completion, disassembly, and formation parking. The safe parking of virtual marshaling trains, in particular, has been a highly sought-after research area, while research on variable tracking distances has often been overlooked. Furthermore, since most railways currently utilize CTCS-2 and CTCS-3 train control systems for train operation, how to ensure system compatibility while simultaneously increasing railway capacity and ensuring train safety through certain control strategy improvements and communication equipment upgrades has become a pressing issue.

[0004] Research is currently underway on the technology and implementation methods for vehicle-to-vehicle communication, which provides the potential for virtual train formation and provides sufficient security guarantees. Existing research primarily considers using IEEE 802.11p, also known as WAVE (Wireless Access in the Vehicular Environment) technology, to achieve vehicle-to-vehicle communication. During this communication process, the two vehicles primarily transmit information such as position, speed, and acceleration. Generally, trains in a virtual formation can obtain information about their neighbors. The following train can then use this information to adjust its speed and acceleration, thereby better tracking the preceding train.

[0005] The CTCS-3 train control system's primary process for ensuring train operation safety is as follows: onboard equipment receives information such as train position, equipment status ahead, train integrity, and track circuit occupancy, which is transmitted via the GSM-R wireless communication network to the Radio Block Center (RBC) and the Station Interlocking System (CBI). The station interlocking system establishes a safe route based on this information and provides signal authorization to the RBC. Simultaneously, the CTC transmits temporary speed limit information and dispatching commands to the RBC. The RBC then integrates this information to generate a driving permit (MA) and transmits line parameters, temporary speed limit, and other information to the onboard equipment. The onboard equipment then generates a speed-distance pattern based on this information, and the Automatic Train Operation (ATO) controls train operation safely. The CTCS-4 train control system, which eliminates track circuits, will inevitably require a large-scale upgrade of infrastructure, resulting in significant time and financial costs. In addition, since both CTCS-3 and CTCS-2 levels require track circuit support, it is not conducive to level switching between trains operating at different train control levels. Therefore, the present invention still uses the CTCS-3 level train control system as the design basis, taking into account equipment compatibility to the greatest extent. Summary of the Invention

[0006] In view of the problems existing in the prior art, the present invention provides a virtual marshaling full-state switching control system and method based on vehicle-to-vehicle communication.

[0007] The technical solution adopted in the present invention is:

[0008] A virtual marshaling full-state switching control method based on vehicle-to-vehicle communication includes the following steps:

[0009] Take two trains as an example, the first train is the front train and the second train is the rear train; the control method for multiple trains is the same as that for two trains;

[0010] According to the train operation status and communication status, the train status is switched according to the location; the status includes formation operation status, independent operation status, unexpected disassembly status and complete disassembly status;

[0011] If two trains pass through a station or stop at a station, and if they are running in the same direction and communication is normal, the first train to leave the station is the leading train. After the leading train passes the switch, it controls the trailing train to pass the switch and sends a platooning request to the leading train. After receiving the signal, the leading train determines whether to form a platoon with the trailing train. If so, the trailing train adjusts its speed and coupling distance with the leading train to enter a platooning state. Otherwise, each train enters an independent operation state.

[0012] When two trains are in the zone, if they have not yet been successfully marshaled or are in independent operation, and communication is normal, and there is no switch within a certain distance ahead, the rear train will send a platooning operation request to the front train. After receiving the signal, the front train will determine whether to form a platoon with the rear train. If so, the rear train will adjust its speed and coupling distance with the front train to enter the platooning operation state, otherwise they will enter the independent operation state.

[0013] If a train is in formation and there is a switch ahead and the two trains are running in different directions, there is a communication anomaly, or the train is running in extreme weather, the speed of the rear train and the coupling distance with the front train will be controlled to enter the complete decoupling state. If the coupling distance and speed between the front and rear trains do not meet the set requirements, the train will switch to the unexpected decoupling state.

[0014] For trains in an unexpected disorganized state, if the conditions for platooning are met, the rear train will adjust its speed and coupling distance with the front train to resume platooning. If the conditions for platooning are not met, the train will switch to a fully disorganized state or independent operation.

[0015] For trains in a fully disassembled state, if the conditions for platooning are met, the rear train will adjust its speed and distance from the front train to resume platooning; if the conditions for platooning are not met, the train will switch to independent operation.

[0016] If two trains stop or brake directly at the station, if the trains in platoon operation stop at the station, the rear train adjusts its speed and the front and rear trains arrive at the stopping point and stop in turn; if the trains in platoon operation stop within the operating section, the rear train maintains the same operating status as the front train through train-to-train communication; if the front train encounters an accident in the platoon operation, a signal is sent to the rear train and emergency braking is performed at the same time.

[0017] Furthermore, the formation operation state satisfies the following conditions:

[0018] |p A -p B -S m |≤th S

[0019] |v A -v B |≤th v

[0020] Where: p A 、p B are the positions of the front and rear vehicles respectively, S m is the safety margin, v A and v B are the speeds of the front and rear vehicles respectively, th S and th v They are the maximum allowable margins of displacement difference and speed difference respectively;

[0021] The conditions for platooning are that the two trains are running in the same direction, communication is normal, the front and rear trains agree to form a team, there are no switches on the route ahead within a certain distance, and the speeds and coupling distances of the two trains meet the platooning conditions; the coupling distances are as follows:

[0022] C d =p A -p B -S m

[0023] Where: C d is the coupling distance, p A 、p B are the positions of the front and rear vehicles respectively, S m For safety margin.

[0024] Furthermore, in the formation operation state, t=t v Tracking distance I(t v ) is calculated as follows:

[0025]

[0026] Where: m B is the mass of the rear vehicle, F B is the traction force on the following vehicle at that moment, f B is the resistance experienced by the following vehicle, β B is the braking rate of the following vehicle, C d (t v ) is t=t v The coupling distance between the two vehicles, S m is the safety margin, v′ B The speed after the following vehicle accelerates.

[0027] Furthermore, the following process of adjusting the speed and coupling distance with the leading vehicle to enter the platooning state is as follows:

[0028] If the speed of the front car is greater than that of the rear car, that is, v A >v B And C d >0; the following vehicle receives the formation command and obtains the speed and position information of the leading vehicle through vehicle-to-vehicle communication; controls the following vehicle to accelerate to v B′>v A The vehicle speed is increased to reduce the distance to the vehicle in front to a preset value; the vehicle then decelerates until the conditions for platooning are met and switches to platooning.

[0029] If the speed of the front car is equal to the speed of the rear car but the distance between the two cars is too large, that is, v A =v B , C d >0; the following vehicle receives the formation command and obtains the speed and position information of the leading vehicle through vehicle-to-vehicle communication; controls the following vehicle to accelerate to v B ′>v A The vehicle speed is increased to reduce the distance to the vehicle in front to a preset value; the vehicle then decelerates until the conditions for platooning are met and switches to platooning.

[0030] If the speed of the front car is less than that of the rear car, that is, v A <v B And C d >0; if the distance between the two vehicles is greater than the preset value, the rear vehicle will accelerate to shorten the distance to the front vehicle to the preset value, and then decelerate until the conditions for the platooning state are met; if the speed of the rear vehicle is greater than the preset value, it will directly decelerate until the conditions for the platooning state are met; after the conditions for the platooning state are met, it will switch to the platooning state.

[0031] Furthermore, the failure to meet the formation operation conditions includes the following situations:

[0032] There is no train ahead of the train that needs to be formed, the train is running in the same direction as the train ahead, and the train ahead is in a communication interruption state.

[0033] Furthermore, during the control process, the coupling distance C is maintained. d >0, if C d <0, the leading and trailing trains receive safety alerts, controlling the leading train to accelerate or the trailing train to decelerate, increasing the distance between the two trains.

[0034] A control system for a virtual marshaling full-state switching control method based on vehicle-to-vehicle communication, comprising a state control unit, ground equipment, a train operation control unit, a communication system, and a dispatching center;

[0035] A status control unit is used to determine the status between the train and the preceding vehicle;

[0036] The train operation control unit is used to determine the coupling distance between the rear and front trains, and the speed of the rear and front trains; and to control the operation of the train according to the control strategy;

[0037] Communication system, used to control vehicle-to-vehicle communication and vehicle-to-ground communication;

[0038] A dispatch center for planning, command issuance, and monitoring;

[0039] Ground equipment is used to connect with the dispatching center and send commands to the train.

[0040] The beneficial effects of the present invention are:

[0041] (1) The present invention considers the entire process of train departure, marshalling, and parking, and considers the train's operation and braking at stations and intervals, comprehensively and in detail covering all possible tracking situations, ensuring the train's operational safety and improving transportation efficiency;

[0042] (2) The control system of the present invention only needs to add vehicle-to-vehicle communication on the basis of the existing control system, which greatly improves the compatibility of equipment and reduces the consumption of time and economic costs;

[0043] (3) Through vehicle-to-vehicle communication, the present invention can obtain information such as integrity reports, control commands, feedback, and fault alarms from adjacent trains. Based on the current operating status of the train and the system's dispatching instructions, the present invention can further obtain train control commands and speed-distance pattern curves, and the train operation can be controlled by the train automatic operation system.

[0044] (4) The inter-vehicle spacing of the virtual marshaling convoy of the present invention is smaller, and higher requirements are placed on the accuracy of the tracking distance. Therefore, the train onboard equipment should quickly respond to the adjustment strategy of the tracking speed based on the information obtained from the vehicle-to-vehicle communication, the radio block center, and the ground equipment; if the rear vehicle crosses the safety boundary, an alarm will be issued to inform the front vehicle to accelerate or control the rear vehicle to decelerate. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a structural diagram of the control system of the present invention.

[0046] Figure 2 This is a flow chart of the virtual grouping state switching of the present invention.

[0047] Figure 3 This is a schematic diagram of a train departure or passing through a station according to the present invention.

[0048] Figure 4 Schematic diagram of the process of train switching to formation running state in the present invention. DETAILED DESCRIPTION

[0049] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0050] like Figure 2 As shown, a virtual marshaling full-state switching control method based on vehicle-to-vehicle communication includes the following steps:

[0051] Take two trains as an example, the first train is the front train and the second train is the rear train; the control method for multiple trains is the same as that for two trains;

[0052] According to the train operation status and communication status, the train status is switched according to the location; the status includes formation operation status, independent operation status, unexpected disassembly status and complete disassembly status;

[0053] In the initial state, multiple trains pass through or stop at the station; one train occupies one track, such as Figure 3 This state includes three scenarios: two trains passing through a station on different tracks and entering the same line; one train passing through a station and the other preparing to depart at the station; and both trains stopping at the station.

[0054] First, determine whether there are multiple trains departing from the station at the same time. If so, and the two trains are running in the same direction and the communication equipment can work normally, the train that leaves the station first will serve as the front train and pass through the switch to enter the track section. After the front train has completely passed the switch, the switch will be controlled to switch to the direction of the track where the rear train is located. After the switch is switched and locked, the on-board equipment of the rear train receives the switch locking completion signal, controls the rear train to run and pass through the switch, and sends a formation operation application to the front train at the same time. After receiving the signal, the front train determines whether to form a formation with the rear train. If so, the rear train adjusts its speed to form a formation with the front train and enters the formation operation state (condition one); if not, the front and rear trains enter independent operation states respectively (condition two).

[0055] If only one train departs during this period, the train preparing to depart or pass through the station will enter the track section through the switch. If there is no train in front of the train that needs to be marshaled or the train in front is in a communication interruption state, it will enter an independent operation state.

[0056] If a train is running in a section but there is no train running in the same direction in the section ahead, or the train ahead is in a communication interruption state, or the adjacent train ahead rejects the application for convoy operation, the train will also be in an independent operation state.

[0057] Even if two trains depart at the same time, they may not be able to enter the platooning state directly because the distance between the trains may be too large and the speeds of the two trains may be inconsistent. Therefore, it is necessary to adjust the speeds of the front and rear trains to allow the two trains to run in platoon. The control process is similar to the method in the interval operation state.

[0058] When two trains are in the zone operation state, if they have not yet been successfully marshaled or are in the independent operation state, if they encounter a train in the same direction of operation in front and the train's communication equipment is normal, and there is no switch in the route ahead for a long distance, they will send a formation operation request to the front train. When the front train confirms the request and agrees to the formation operation, the rear train will adjust the tracking target point to the tail position of the front train and adjust the speed so that the two trains can reach the formation operation state (as shown in condition 4). During the formation process, the distance between the two trains is usually greater than the minimum distance, which is the safety margin S mAs an extension of the relative braking distance (the distance traveled when the rear vehicle adjusts to the same speed as the front vehicle), the distance greater than the safety margin is called the coupling distance C. d , C d =p A -p B -S m , and the speeds of the two vehicles may encounter three situations, namely: v A >v B 、v A =v B 、v A <v B .

[0059] The detailed process is as follows:

[0060] (1) If the speed of the front vehicle is greater than that of the rear vehicle, that is, v A >v B And C d >0; the following vehicle receives the formation command and obtains the speed and position information of the leading vehicle through vehicle-to-vehicle communication; controls the following vehicle to accelerate to v B ′>v A speed, reducing the distance to the preceding vehicle to a preset value; then decelerating until the conditions for the platooning state are met and switching to the platooning state; where v B ′ is the set speed, which meets the speed limit requirements of the section.

[0061] During the train tracking adjustment process, according to the definition of relative braking distance, since the speeds of the front and rear trains are time-varying, the coupling distance is also time-varying. v , the coupling distance can be calculated using the following method:

[0062]

[0063] Where: m B is the mass of the rear vehicle, F B is the traction force on the following vehicle at that moment, β B <0 is the braking rate of the following vehicle at that moment, f B is the resistance of the following vehicle, including the basic resistance f b (v B ) and additional resistance f a (v B ,p B ,t).

[0064] (2) If the speed of the leading vehicle is equal to that of the trailing vehicle but the distance between the two vehicles is too large, that is, v A =v B , C d>0; the following vehicle receives the formation command and obtains the speed and position information of the leading vehicle through vehicle-to-vehicle communication; controls the following vehicle to accelerate to v B ′>v A speed, reducing the distance to the vehicle in front to a preset value; then decelerating until the conditions for the platooning operation state are met and switching to the platooning operation state; the coupling distance calculation method is as above.

[0065] (3) If the speed of the front vehicle is less than that of the rear vehicle, that is, v A <v B And C d >0; the control strategy of the following vehicle is determined based on the distance between the two vehicles and the speed difference. If the distance between the two vehicles is greater than the preset value, the following vehicle accelerates to shorten the distance to the leading vehicle to the preset value, and then decelerates until the conditions for platooning are met; if the speed of the following vehicle is greater than the preset value, it decelerates directly until the conditions for platooning are met; after the conditions for platooning are met, it switches to platooning. The coupling distance C when the following vehicle directly decelerates d The calculation method is as follows:

[0066]

[0067] It can be obtained that the train is at t=t v When , the tracking distance calculation model is as follows:

[0068]

[0069] The tracking distance of trains running under virtual marshaling depends not only on the speed of the front and rear trains, but also on the braking rate β of the rear train. B , the resistance force f on the following vehicle B , the traction force F on the rear vehicle B The tracking distance calculation model only requires the current train to know its own operating attributes and the speed of the preceding train, without having to know the position of adjacent trains. This is an emergency measure when positioning fails.

[0070] The formation operation status meets the following conditions:

[0071] |p A -p B -S m |≤th S

[0072] v A -v B ≤th v

[0073] Where: p A 、p B are the positions of the front and rear vehicles respectively, S mis the safety margin, v A and v B are the speeds of the front and rear vehicles respectively, th S and th v They are the maximum allowable margins of displacement difference and speed difference respectively;

[0074] The conditions for platooning are that the two trains are running in the same direction, communication is normal, the front and rear trains agree to form a team, there are no switches on the route ahead within a certain distance, and the speeds and coupling distances of the two trains meet the platooning conditions.

[0075] If the train is running in a convoy, if there is a switch within a certain distance ahead and the two trains are running in different directions, there is a communication abnormality, or the train is running in extreme weather, the speed of the rear train and the coupling distance with the front train will be controlled to enter a completely uncoupled state (condition six); if the coupling distance and speed between the front and rear trains do not meet the set requirements, the train will switch to an unexpected uncoupled state (condition five).

[0076] The specific control process is as follows:

[0077] (1) If two trains pass through a station without stopping and are running in the same direction, the switches for the trains in formation operation are continuously locked to ensure that the trains in the formation pass through the same switch continuously, reducing the time for information transmission and opening authority in the switch control, and further improving operation efficiency.

[0078] (2) If the braking performance of the front and rear vehicles is different, the acceleration of the front vehicle is greater than that of the rear vehicle, or the front vehicle is going downhill while the rear vehicle is going uphill, etc., resulting in p A -p B -S m >th S or v A -v B >th v When the train switches to the unexpected disassembly state.

[0079] (3) If: there is a switch in the section ahead of the two trains and the two trains are running in different directions due to various reasons; there is a communication interruption between the front and rear trains; the trains are running in extreme weather (such as heavy snow or hail), in any of these three situations, the on-board equipment of the rear train should immediately obtain the decoupling instruction and control the rear train to slow down, increase the distance from the front train, and switch to the complete decoupling state.

[0080] Before passing a switch, the safety distance between trains must be extended to allow the switch to switch back to the correct position before allowing another train to pass. At this time, the tracking distance before the train passes the switch should be the absolute braking distance plus the distance the following train runs when the switch is switched plus a safety margin. The reason for increasing the distance between the leading and trailing trains to the absolute braking distance before the switch is turned is to allow the following train to brake safely in the event of a switch switching failure. In order to prevent the following train from passing before the switch is fully locked, the distance the following train runs during the switch switching to locking process must be considered.

[0081] For a train in an unexpectedly disassembled state, if the conditions for platooning operation are met, the rear train will adjust its speed and coupling distance with the front train to resume the platooning operation state (condition seven); if the conditions for platooning operation are not met, it will switch to a completely disassembled state or an independent operation state (condition three).

[0082] Since the speed and displacement difference between the train in the unexpected disassembly state and the preceding train is within the adjustable range, if the formation operation conditions are met and the preceding and following trains still have formation operation instructions, the following train can be controlled to adjust its speed to p A -p B -S m ≤th S , v A -v B ≤th v , thus restoring to the formation operation state.

[0083] The train speed in the unexpected disassembly state will still face v A >v B 、v A =v B 、v A <v B Three cases, but the coupling distance C d There will be two situations: greater than 0 and less than 0. The corresponding control process can be described as:

[0084] If the coupling distance is greater than 0, the control process is the same as that for the marshaling operation state described above. If the coupling distance is less than 0, the following vehicle has crossed the safety margin defined by the safety margin. At this point, both the leading and following vehicles receive a safety alert and immediately accelerate the leading vehicle or decelerate the following vehicle, increasing the distance between them.

[0085] The premise for ensuring train safety is that the speed and acceleration of the rear train are consistent with those of the front train, and the distance between the two trains does not exceed the safety boundary, that is, the coupling distance C. dIt cannot be less than 0. However, since the train is affected by the environment and the braking performance of the train during operation, the situation where the coupling distance is less than 0 is still unavoidable. Therefore, when designing the safety margin, the distance impact caused by various safety hazards is taken into account. The resulting safety margin includes: the distance added by the train positioning error, the additional running distance of the rear vehicle caused by the train communication delay and control delay, the distance traveled by the train from the time of preparing for braking to the start of braking, and the sum of the safety reserve distances caused by the inconsistent braking performance of the front and rear vehicles due to external factors such as external disturbances and uneven rails. If the formation operation conditions are not met, that is, there is a switch in the section ahead and the two vehicles are running in different directions, or the communication between the front and rear vehicles is interrupted, or the adjacent front vehicle rejects the formation application, the train switches from the accidental disassembly state to the complete disassembly state.

[0086] For a train in a fully disassembled state, if the conditions for platoon operation are met, the rear train will adjust its speed and distance from the front train to resume the platoon operation state (condition four); if the conditions for platoon operation are not met, it will switch to an independent operation state (condition three).

[0087] If there is no train ahead of the train that requires platooning, or the train's direction of travel is inconsistent with the preceding train's, or the preceding train is experiencing communication loss, the train switches to independent operation, controlled by the CTCS-3 train control system. If, after the preceding train is disbanded, the preceding train's communication status is good, it is traveling in the same direction as the preceding train and has accepted the preceding train's platooning request, and there are no switches along the route ahead for a considerable distance, the preceding train and the preceding train are controlled to transition to platooning by adjusting speed and distance, following the control process described above.

[0088] If two trains stop or brake directly at the station, if the trains in platoon operation stop at the station, the rear train adjusts its speed and the front and rear trains arrive at the stopping point and stop in turn; if the trains in platoon operation stop within the operating section, the rear train maintains the same operating status as the front train through train-to-train communication; if the front train encounters an accident in the platoon operation, a signal is sent to the rear train and emergency braking is performed at the same time.

[0089] In the final state, the primary consideration is the situation where multiple trains operating in formation arrive at a station to stop or brake directly. For trains operating independently, the CTCS-3 train control system controls the trains to stop. For trains in unexpected or complete separation states, when the coupling distance between the two trains is greater than 0, the tracking distance between the two trains is greater than the tracking distance in formation operation. Therefore, reference can be made to the parking control methods for trains in formation operation to ensure safe parking. When the coupling distance between the two trains is less than 0, the trains are first controlled to enter formation operation, followed by a stop.

[0090] The control process is as follows:

[0091] (1) If the trains running in formation pass through the switch in turn and stop at different tracks, the control process is similar to the process of the trains being completely uncoupled before the switch. The rear train will first slow down and increase the distance between the two trains to the sum of the absolute braking distance, the distance traveled by the rear train during the switch switching to locking process, and the safety margin. Then, the front and rear trains will arrive at their respective parking points and stop in turn.

[0092] (2) If a train in formation stops directly within a section, the following train should take each state of the leading train during the process of stopping with maximum braking force as a protection target. Through timely inter-train communication, the following train can accelerate, decelerate and brake almost at the same time as the leading train, thereby ensuring the safety of the train stopping in this situation.

[0093] (3) If a train integrity loss fault occurs on the leading train or an obstacle appears in front of the line when two trains are running in formation, the trailing train will receive the fault information of the leading train or the obstacle information of the trailing line through vehicle-to-vehicle communication and vehicle-to-ground communication, triggering an emergency braking operation.

[0094] (4) If the front car hits an obstacle in front when two cars are running in formation, that is, the front car comes to an emergency stop, the monitoring intensity and sensitivity of the safety monitoring system should be strengthened to avoid related accidents and ensure the safe operation of the virtual train.

[0095] A control system for a virtual marshaling full-state switching control method based on vehicle-to-vehicle communication, comprising a state control unit, ground equipment, a train operation control unit, a communication system, and a dispatching center;

[0096] A status control unit is used to determine the status between the train and the preceding vehicle;

[0097] The train operation control unit is used to determine the coupling distance between the rear and front trains, and the speed of the rear and front trains; and to control the operation of the train according to the control strategy;

[0098] Communication system, used to control vehicle-to-vehicle communication and vehicle-to-ground communication;

[0099] A dispatch center for planning, command issuance, and monitoring;

[0100] Ground equipment is used to connect with the dispatching center and send commands to the train.

[0101] Figure 2 The conditions shown in are detailed below:

[0102] Condition 1: The two trains depart from the station at the same time and in the same direction, the communication equipment can work normally, and the front and rear trains agree to form a group. A -p B -S m ≤th S , vA -v B ≤th v .

[0103] Condition 2: Only one train departs during this period and there is no train running in the same direction in the preceding section, or the preceding train is in a communication interruption state, or the adjacent preceding train refuses the application for platoon operation.

[0104] Condition three: There is no train running in the same direction in the section ahead of the train running in the section, or the train ahead is in a communication interruption state, or the adjacent train ahead rejects the application for platoon operation.

[0105] Condition 4: The two trains are running in the same direction, the communication equipment can work normally, the front and rear trains agree to form a group, and there is no switch in the long distance ahead. A -p B -S m ≤th S , v A -v B ≤th v .

[0106] Condition 5: p A -p B -S m >th S or v A -v B >th v .

[0107] Condition 6: There is a switch in the section ahead of the two trains and due to various reasons the two trains are running in different directions, or there is a communication interruption between the front and rear trains, or the trains are running in extreme weather (such as heavy snow or hail).

[0108] Condition 7: All platooning conditions are met and the two vehicles in front and behind still have platooning instructions, p A -p B -S m ≤th S , v A -v B ≤th v .

[0109] Condition 8: A train in the virtual coupled convoy or convoy stops at the next station or a train integrity loss failure occurs or an obstacle appears on the line ahead.

[0110] This invention leverages the CTCS-3 train control system to implement a virtual train control system by incorporating train-to-train communication. The improved train control system only adds train-to-train communication, significantly improving device compatibility and reducing time and cost. Unlike the CTCS-3 train control system, the addition of train-to-train communication allows the train's onboard safety computer to obtain information not only from the radio block center and ground equipment but also from adjacent trains, including speed information. This allows the train to promptly adjust its speed and tracking strategy for safer and more efficient tracking, shortening the tracking distance. Through train-to-train communication, the train can also obtain integrity reports, control commands and feedback, and fault alarms from adjacent trains. Furthermore, based on the train's current operating status and system dispatch instructions, train control commands and speed-distance pattern curves are generated. The automatic train operation (ATO) controls train operation, achieving state transitions, such as controlling train disassembly and reassembly. Furthermore, due to the closer inter-vehicle spacing in virtual marshaling convoys, tracking distance accuracy is required to be even more accurate. Therefore, onboard train equipment must rapidly adjust tracking speed based on information received from inter-vehicle communications, the radio block center, and ground equipment. If the trailing train crosses a safety boundary, an alarm will sound, instructing the leading train to accelerate or decelerate the trailing train. The safe position a train can reach, as provided by the driving permit, is no longer the entrance to the block section where the preceding train is located. Instead, it specifies potential danger points, including incompletely locked switches and the rear of the leading train that has established inter-vehicle communications with the trailing train.

Claims

1. A virtual marshaling full-state switching control method based on vehicle-to-vehicle communication, characterized in that: The following steps are involved: Take two trains as an example, the first train is the front train and the second train is the rear train; the control method for multiple trains is the same as that for two trains; According to the train operation status and communication status, the train status is switched according to the location; the status includes formation operation status, independent operation status, unexpected disassembly status and complete disassembly status; If two trains pass through a station or stop at a station, and if they are running in the same direction and communication is normal, the first train to leave the station is the leading train. After the leading train passes the switch, it controls the trailing train to pass the switch and sends a platooning request to the leading train. After receiving the signal, the leading train determines whether to form a platoon with the trailing train. If so, the trailing train adjusts its speed and coupling distance with the leading train to enter a platooning state. Otherwise, each train enters an independent operation state. When two trains are in the zone, if they have not yet been successfully marshaled or are in independent operation, and communication is normal, and there is no switch within a certain distance ahead, the rear train will send a platooning operation request to the front train. After receiving the signal, the front train will determine whether to form a platoon with the rear train. If so, the rear train will adjust its speed and coupling distance with the front train to enter the platooning operation state, otherwise they will enter the independent operation state. If a train is in formation and there is a switch ahead and the two trains are running in different directions, there is a communication anomaly, or the train is running in extreme weather, the speed of the rear train and the coupling distance with the front train will be controlled to enter the complete decoupling state. If the coupling distance and speed between the front and rear trains do not meet the set requirements, the train will switch to the unexpected decoupling state. For trains in an unexpected disorganized state, if the conditions for platooning are met, the rear train will adjust its speed and coupling distance with the front train to resume platooning. If the conditions for platooning are not met, the train will switch to a fully disorganized state or independent operation. For trains in a fully disassembled state, if the conditions for platooning operation are met, the rear train will adjust its speed and coupling distance with the front train to resume platooning operation; if the conditions for platooning operation are not met, the train will switch to independent operation. In the formation operation state, t=t v Tracking distance I(t v ) is calculated as follows: Where: m B is the mass of the rear vehicle, F B is the traction force on the following vehicle, f B is the resistance experienced by the following vehicle, β B is the braking rate of the following vehicle, C d (t v ) is t=t v The coupling distance between the two vehicles, S m is the safety margin, v′ B is the speed of the following vehicle after acceleration; v A and v B are the speeds of the front and rear vehicles respectively; t v For a given moment; If two trains stop or brake directly at the station, the rear train adjusts its speed and the front and rear trains arrive at the stopping point and stop in turn; if a train stops within the operating section in platoon operation, the rear train maintains the same operating status as the front train through train-to-train communication; if an accident occurs with the front train in platoon operation, a signal is sent to the rear train and emergency braking is performed at the same time.

2. A virtual marshaling full-state switching control method based on vehicle-to-vehicle communication according to claim 1, characterized in that: The formation operation state meets the following conditions: |p A -p B -S m |≤th S |v A -v B |≤th v Where: p A 、p B are the positions of the front and rear vehicles respectively, S m is the safety margin, v A and v B are the speeds of the front and rear vehicles respectively, th S and th v They are the maximum allowable margins of displacement difference and speed difference respectively; The conditions for platooning are that the two trains are running in the same direction, communication is normal, the front and rear trains agree to form a team, there are no switches on the route ahead within a certain distance, and the speeds and coupling distances of the two trains meet the platooning conditions; the coupling distances are as follows: C d =p A -p B -S m Where: C d is the coupling distance, p A 、p B are the positions of the front and rear vehicles respectively, S m For safety margin.

3. A virtual marshaling full-state switching control method based on vehicle-to-vehicle communication according to claim 2, characterized in that: The process of the following vehicle adjusting its speed and coupling distance with the leading vehicle to enter the platooning state is as follows: If the speed of the front car is greater than that of the rear car, that is, v A >v B And C d >0; the following vehicle receives the formation command and obtains the speed and position information of the leading vehicle through vehicle-to-vehicle communication; controls the following vehicle to accelerate to v B ′>v A The vehicle speed is increased to reduce the distance to the vehicle in front to a preset value; the vehicle then decelerates until the conditions for platooning are met and switches to platooning. If the speed of the front car is equal to the speed of the rear car but the distance between the two cars is too large, that is, v A =v B , C d >0; the following vehicle receives the formation command and obtains the speed and position information of the leading vehicle through vehicle-to-vehicle communication; controls the following vehicle to accelerate to v B ′>v A The vehicle speed is increased to reduce the distance to the vehicle in front to a preset value; the vehicle then decelerates until the conditions for platooning are met and switches to platooning. If the speed of the front car is less than that of the rear car, that is, v A <v B And C d >0; if the distance between the two vehicles is greater than the preset value, the rear vehicle will accelerate to shorten the distance to the front vehicle to the preset value, and then decelerate until the conditions for the platooning state are met; if the speed of the rear vehicle is greater than the preset value, it will directly decelerate until the conditions for the platooning state are met; after the conditions for the platooning state are met, it will switch to the platooning state.

4. The method for controlling full-state switching of virtual marshaling based on vehicle-to-vehicle communication according to claim 1, characterized in that: The conditions for formation operation not being met include the following situations: There is no train ahead of the train that needs to be formed, the train is running in the same direction as the train ahead, and the train ahead is in a communication interruption state.

5. The method for controlling full-state switching of virtual marshaling based on vehicle-to-vehicle communication according to claim 2, characterized in that: During the control process, keep the coupling distance C d >0, if C d <0, the leading and trailing trains receive safety alerts, controlling the leading train to accelerate or the trailing train to decelerate, increasing the distance between the two trains.

6. The control system of any one of the virtual marshaling full-state switching control methods based on vehicle-to-vehicle communication according to claims 1 to 5, characterized in that: Including status control unit, ground equipment, train operation control unit, communication system, and dispatching center; A status control unit is used to determine the status between the train and the preceding vehicle; The train operation control unit is used to determine the coupling distance between the rear and front trains, and the speed of the rear and front trains; and to control the operation of the train according to the control strategy; Communication system, used to control vehicle-to-vehicle communication and vehicle-to-ground communication; A dispatch center for planning, command issuance, and monitoring; Ground equipment is used to connect with the dispatching center and send commands to the train.

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