Cooperative control method for heavy-load combined train based on coupler force closed loop

Abstract

The invention discloses a cooperative control method for a heavy haul railway long and large combination train based on a coupler force closed loop in order to solve the problem that operation safety is threatened due to unstability and breakage of a coupler caused by overlarge longitudinal impact force in the traction braking process of the long and large marshalling train. According to the method, coupler force is introduced into a control system of a locomotive to form a unit train coupler force closed-loop control system in a marshalling train, and traditional locomotive control is changed into train control. According to the method, the purpose of minimizing coupler force of slave control locomotives and front locomotives in a group is achieved, a distributed cooperative control strategy is adopted for unit trains in the group, the purpose of equivalently decomposing the long and large heavy-load combined train into unit trains running independently is achieved with the fact that stress of front coupler of each slave control locomotive is almost zero. And automatic driving operation of the unit trains in the marshalling is realized. By recognizing the stress change trend of the couplers and adopting a coupler force closed-loop active control mode, the overlarge impact force of the train couplers is relieved, and the running safety of the whole heavy-load train is guaranteed.

Description

Technical Field

[0001] The present invention relates to the fields of heavy-haul railway locomotive and train control, automatic control systems, etc., and particularly relates to a cooperative control method for a heavy-haul combined train. Background Art

[0002] Railway transportation, especially heavy-haul railway transportation, has been widely emphasized by railways around the world due to its large transportation capacity, high efficiency, and low transportation cost, and has developed rapidly worldwide.

[0003] By increasing the number of train formations and synchronously towing multiple locomotives, it is a common method to improve the transportation capacity of heavy-haul railways. However, the synchronous towing of multiple locomotives requires highly synchronous actions of each locomotive. If the actions between locomotives are not synchronous, it may cause squeezing or pulling phenomena between the vehicles of the heavy-haul train, seriously affecting railway transportation safety. To achieve synchronous operation of locomotives, the master locomotive needs to transmit control commands to the slave locomotives in real time, and the slave locomotives also need to promptly respond to the control commands from the master locomotive.

[0004] The operating environment of heavy-haul lines is usually complex and changeable (such as curves, bridge and tunnel sections, switches, transition sections, etc.), making the problem of longitudinal impulse of trains prominent. Long heavy-haul trains have a large number of formations and a large total weight, requiring strong traction power, and their braking distances are also greatly increased. The longer the train formation, the more obvious the longitudinal impulse caused by the time difference of traction / braking forces between different vehicles. The large-scale operation of ten-thousand-ton heavy-haul combined trains, while effectively improving railway transportation capacity, results in increased longitudinal forces on locomotives and rolling stocks. The connecting parts of the vehicles have to bear huge tensile, compressive, and impact forces. Once a failure occurs in the connecting device, the consequences are serious. Adjacent vehicles of heavy-haul trains are connected by couplers. Excessive longitudinal impulse of the train is likely to cause the coupler to become unstable and break, triggering train safety accidents and threatening the safe operation of the train.

[0005] The traction power of a train is generated by a locomotive. The traction force of a locomotive comes from the adhesion between the locomotive wheels and the rail via the traction motor. The locomotive control system converts the torque of the traction motor to obtain the traction force of the train, which is used as the feedback value of the locomotive traction force closed-loop control system. Therefore, the control of the traction force of a locomotive actually controls the torque of the locomotive traction motor.

[0006] Currently, there are two technologies to solve the problem of synchronous locomotive control, namely the locomotive wireless communication distributed control technology Locotrol and the electro-pneumatic braking technology ECP. In the attempt to solve problems such as the instability and fracture of couplers caused by excessive longitudinal impact forces, scientific research and experimental work have focused on researching the dynamic model of heavy-haul trains, optimizing the driving methods of drivers, and strengthening the coupler structure, with little effect. Summary of the Invention

[0007] The object of the present invention is to solve the problem that the excessive impact force caused by the sequential transmission of traction and braking commands of long formation trains composed of multiple trains leads to threats to operation safety such as coupler instability and broken couplers. On the one hand, the present invention proposes a cooperative control method for heavy-haul combined trains based on coupler force closed-loop, and the method includes:

[0008] Step S1: Replace the traditional couplers at the front and rear ends of the locomotive with force-sensing couplers capable of sensing pulling and pressing forces.

[0009] Step S2: Combine the train dynamics model and calculate the trend of coupler force change according to the feedback of the coupler force of the slave locomotive.

[0010] Step S3: Introduce the coupler force of the slave locomotive into the locomotive control system to form a coupler force closed-loop control system for the unit trains within the formation, and realize the autonomous driving operation of the unit trains within the formation.

[0011] Step S4: According to the trend of coupler force change obtained in Step S2, combined with the control commands such as traction, braking, and emergency braking transmitted by the master locomotive through vehicle-to-vehicle communication such as LOCOTROL, timely adjust the traction and braking forces of the slave locomotive to ensure that the coupler impulse force of the train is limited within a safe and small range.

[0012] Further, in the Step S1, the coupler pulling and pressing force is obtained through data fusion by installing a variety of force sensors on the coupler and the coupler box.

[0013] Further, in the Step S2, the calculation of the coupler force change trend is used to judge the traction, braking, and emergency braking states of the preceding vehicle, and this coupler force change trend is obtained by taking the derivative of the measured coupler force, filtering, and combining with the train dynamics model.

[0014] Further, in the Step S3, for the unit train coupler force closed-loop control system, taking the coupler force to be approximately zero as the coupler force target value of this closed-loop control, and taking the measured value of the coupler force of the preceding vehicle of this locomotive as the feedback value of this closed-loop control, upgrade the locomotive control system originally constituted by using motor torque as the feedback to a train control system with coupler force feedback.

[0015] Further, in the Step S4, the coupler force change trend, the speed regulation command transmitted by the master locomotive through vehicle-to-vehicle communication, etc. are used as the inputs of the neural network prediction model, and the model output is used as the torque command of the original locomotive control system to timely and accurately adjust the locomotive traction force and relieve the impact of the train coupler force.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. In the unit train locomotive within a long formation train, a closed-loop control system for the coupler force is formed with the coupler force as the feedback quantity, achieving the leap from locomotive control to train control and subverting the existing control modes of railway trains at home and abroad.

[0018] 2. The unit train locomotive within a long formation train actively and directly measures the coupler force between itself and the end of the preceding train formation and its changing trend, maintains the minimum dynamic and static coupler forces through closed-loop control, actively adjusts the traction force according to the changing trend of the coupler force to mitigate the impact of the coupler force, making the coupler force distribution of the entire train more uniform and the operation of the long heavy-haul train safer.

[0019] 3. The coupler force closed-loop control method of the present invention allows different types and models of locomotives to be used for traction within the formation train, such as a formation heavy-haul train composed of any mixed formation of DC locomotives, AC locomotives, and even diesel locomotives (if required).

[0020] 4. The coupler force closed-loop control method of the present invention has a redundant functional role with the vehicle-vehicle remote communication of the entire formation train, such as LOCOTROL control. Even if abnormal situations such as a short-term interruption of the locomotive-locomotive remote communication occur, it does not affect the normal operation of the entire formation train, and the operation safety and reliability are higher.

[0021] 5. It simply realizes the autonomous driving operation of the unit train within the long heavy-haul combined train formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention has the following drawings:

[0023] Figure 1 The implementation process of the coordinated control of the heavy-haul combined train based on the coupler force closed-loop formed by the method of the present invention.

[0024] Figure 2 The schematic diagram of the position where the method of the present invention is implemented and the structural composition of the long heavy-haul combined train.

[0025] Figure 3 The implementation and input-output logic diagram of the method of the present invention.

[0026] Figure 4 The working principle and implementation schematic diagram of the unit train control system based on the coupler force closed-loop formed by the method of the present invention and the original locomotive control system. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] To make the objectives, advantages, and features of the present invention more obvious, the present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0028] Example 1:

[0029] As Figure 1As shown in the figure, a cooperative control method for a combined train based on a closed-loop coupler force specifically includes:

[0030] Step S1: Replace the traditional coupler at the front and rear ends of the locomotive with a force-measuring coupler capable of sensing tensile and compressive forces.

[0031] Step S2: Calculate the change trend of the coupler force according to the train dynamics model and the feedback of the coupler force of the slave locomotive.

[0032] Step S3: Introduce the coupler force of the slave locomotive into the locomotive control system to form a coupler force closed-loop control system for the unit trains within the formation, and realize the automatic driving operation of the unit trains.

[0033] Step S4: According to the change trend of the coupler force obtained in Step S2, combined with the control commands such as traction, braking, and emergency braking transmitted from the master locomotive through vehicle-to-vehicle communication, timely adjust the traction and braking forces of the slave locomotive to ensure that the coupler impulse force of the train is limited within a safe and small range.

[0034] Further, in Step S1, the coupler tensile and compressive force is obtained through data fusion by installing a variety of force sensors on the coupler and the coupler box.

[0035] Further, in Step S2, the calculated change trend of the coupler force is used to judge the traction, braking, and emergency braking states of the preceding vehicle. This change trend of the coupler force is obtained by taking the derivative of the measured coupler force, filtering, and then combining with the train dynamics model.

[0036] Further, in Step S3, for the coupler force closed-loop control system, the coupler force is approximately zero as the coupler force target value of this closed-loop control, and the measured value of the coupler force of the preceding vehicle of this locomotive is used as the feedback value of this closed-loop control. Input the relevant parameters into the neural network prediction model. The regulator can adopt an improved PID control strategy to adjust the PID parameters online through fuzzy logic.

[0037] Example 2:

[0038] The sensor output of the force-measuring coupler is connected to the locomotive remote input / output module RIOM after filtering and data fusion processing, and the closed-loop control and regulator control algorithm can be realized in the CCU of the locomotive to form a coupler force closed-loop control system for the unit trains within the formation.

[0039] The closed-loop control logic is that the slave locomotive within the formation takes the front coupler force Ff≈0 as the control target, and the rear coupler force Fr pulls this unit train and balances the longitudinal impulse of the train.

[0040] As Figure 2As shown, the method of the present invention aims to make the pulling and pressing force of the coupler between each unit train locomotive in the formation and the leading vehicle almost zero. Each locomotive in the formation adopts a distributed cooperative control strategy, with the control objective of making the force on the coupler of the slave locomotive in front of the train almost zero, so as to decompose the long and heavy combined train into equivalent independent unit trains and realize the automatic driving operation of the unit trains in the formation.

[0041] As Figure 3 shown, by identifying the changing trend of the coupler force and combining it with the train dynamics model and the speed regulation command of the master locomotive, the target value of the traction force of the unit train locomotive is output through the neural network prediction model. The coupler force at the rear of the locomotive pulls the unit train and balances the longitudinal impulse of the train.

[0042] Figure 4 This is the logic diagram and specific implementation schematic of the closed-loop control system for the coupler force of each unit train in the long and heavy train formation constituted by the method of the present invention. The train cooperative control system constituted by the method of the present invention can greatly reduce the excessive impact force of the coupler and ensure the safe operation of the long and heavy combined train.

[0043] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for coordinated control of heavy-load combined trains based on a coupler force closed loop, characterized in that: The method comprises Step S1, replacing the traditional couplers at the front and rear ends of the locomotive with force-measuring couplers capable of sensing tension and pressure; Step S2, introducing the coupler force of the slave locomotive into the locomotive control system to form a coupler force closed-loop control system for the unit train in the formation, thereby realizing automatic driving operation of the unit train in the formation; Step S3, calculating the change trend of the coupler pulling pressure according to the train dynamics model and the feedback of the coupler force from the controlled locomotive; Step S4, according to the coupler force change trend obtained in step S3, combined with the traction, braking, emergency braking and other train control and speed regulation instructions transmitted from the master locomotive via train-to-train communication, timely adjust the traction braking force of the slave locomotive to ensure that the impact force of the train coupler is limited to a safe and small range.

2. A method for coordinated control of heavy-load combination trains based on a coupler force closed loop as claimed in claim 1, characterized in that: In the step S1, the coupler pulling pressure is obtained by installing multiple force sensors on the coupler and the coupler box and fusing the data.

3. A method for coordinated control of heavy-load combination trains based on a coupler force closed loop as claimed in claim 1, characterized in that: In step S2, the coupler force closed-loop control system uses the locomotive front coupler force of approximately zero as the given target value of the coupler force of the coupler force closed-loop control system when the unit train is running stably, and uses the measured value of the locomotive front coupler force as the feedback value of the closed-loop control to form the coupler force closed-loop control system of the unit train.

4. A method for coordinated control of heavy-load combination trains based on coupler force closed loop as claimed in claim 1, characterized in that: In step S3, the measuring and calculating of the coupling force variation trend is obtained by taking the derivative of the measured coupling force, filtering it and combining it with the train dynamics model, and is used to predict the coupling force variation caused by train traction, braking and emergency braking.

5. The method for coordinated control of heavy-load combination trains based on coupler force closed loop according to claim 1, characterized in that: In step S4, in combination with the train dynamics model, the speed control instructions of the master locomotive transmitted by the car-to-car communication and the data on the change trend of the front coupler force of the locomotive of this unit train are input into the neural network prediction model, and a decision is made to output the given value of the closed-loop control system of the front coupler force of the locomotive of this unit train, so as to alleviate and limit the changes of the coupler force and impact force within the allowable range during the train speed regulation process.

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