Method and system for enhancing adhesion braking force based on eddy current brake

Abstract

The invention relates to an adhesion braking force enhancing method and system based on an eddy current brake, and the method comprises the following steps: when a high-speed train carries out emergency braking, a linear eddy current brake enters a working state through excitation current; on the basis of longitudinal non-adhesion braking force generated by matching with a linear eddy current brake, exciting current is controlled by calculating the surplus of the maximum axle load and the actual axle load, so that vertical suction force is in a safe range, and meanwhile, the generated vertical suction force is combined with an adhesion coefficient to calculate an increased high-speed train adhesion force available domain; the available additional adhesion force is fed back to the adhesion braking system to improve the adhesion braking force, and the braking effect of the high-speed train is improved; and in cooperation with longitudinal non-adhesive braking force generated by a linear eddy current brake, efficient matching and utilization of braking force and adhesive force under multiple working conditions are achieved. The system can be applied to any type of linear eddy current brakes, and on the basis of an original high-speed train braking system, the total braking force is further improved, and the braking efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of high-speed train braking, and in particular to a method and system for enhancing adhesion braking force based on eddy current brakes. Background Art

[0002] With the rapid development of high-speed train related technologies, high-speed trains are moving towards higher speed, higher efficiency and higher load. The increase in running speed has also brought new challenges to the performance of the train braking system. Traditional adhesion braking is restricted by the adhesion coefficient, and its maximum braking efficiency can no longer meet the braking needs of the train. Therefore, it is necessary to introduce linear eddy current brakes to further improve the braking efficiency of high-speed trains from the perspective of non-adhesion braking.

[0003] At present, the linear eddy current brakes used in high-speed trains can provide a large amount of non-adhesive braking force for high-speed trains, but there is still room for improvement. Specifically, during the braking process of a high-speed train, the high-speed train braking control system passes an excitation current into the eddy current brake. At this time, the eddy current brake generates an electromagnetic force, which can be divided into a longitudinal braking force opposite to the direction of the train's travel and a vertical suction force perpendicular to the ground. In the existing high-speed train braking system, only the longitudinal braking force generated by the train is fully applied. In most cases, a pre-set braking curve is used, and the potential effect of the vertical suction force is not analyzed, which results in the inability to effectively apply the vertical suction force generated by the eddy current brake. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a method and system for enhancing the adhesion braking force based on an eddy current brake.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] As a first aspect of the present invention, a method for enhancing adhesion braking force based on an eddy current brake is provided, wherein the following steps are performed on a high-speed train including an eddy current brake control system and an adhesion brake control system:

[0007] Obtain the maximum axle weight of the train and the maximum adhesion coefficient between the wheel and rail;

[0008] When the high-speed train enters the braking condition, the eddy current brake is braked by passing the excitation current into the eddy current brake through the eddy current brake control system;

[0009] Monitor train axle weight in real time and calculate the available axle weight surplus on a single train based on the real-time axle weight and the maximum axle weight;

[0010] Monitor the total vertical suction force of all eddy current brakes on a single train section, and compare the monitoring result with the available axle weight surplus of the train section. If the total vertical suction force is greater than the axle weight surplus, adjust the magnitude of the excitation current in the eddy current brake to reduce the total vertical suction force until the total vertical suction force is less than or equal to the axle weight surplus.

[0011] The available additional adhesion of a single train is calculated based on the maximum adhesion coefficient and the total vertical suction force;

[0012] The adhesion braking control system further increases the adhesion braking force based on the available additional adhesion force on the basis of the original adhesion braking force;

[0013] The above-mentioned adhesion braking force enhancement braking process based on the eddy current brake is cyclically executed until the train stops, and the excitation current to the eddy current brake is stopped, thereby ending the braking.

[0014] As an optimal technical solution, the method performs fault detection on the eddy current brake when the high-speed train enters the braking condition. If the eddy current brake works normally, the method proceeds to the next step; if the eddy current brake fails to work normally, an error message is returned, power supply to all eddy current brakes on the bogie where the faulty eddy current brake is located is stopped to end the braking of the brake in advance, and other braking methods are adopted.

[0015] As a preferred technical solution, the available axle weight surplus of the single-section train is calculated as follows:

[0016] N=4*g*(M0-M)

[0017] Where M0 is the maximum axle weight of the train; M is the real-time axle weight of the train.

[0018] As a preferred technical solution, the real-time axle weight of the train is the average axle weight monitored in real time over a period of time.

[0019] As a preferred technical solution, the additional adhesion of the single-section train can be calculated as follows:

[0020] f=μ*F n

[0021] Where, μ is the maximum adhesion coefficient; F n It is the total vertical suction force of all eddy current brakes in a single train.

[0022] As an optimal technical solution, the single cycle period of the adhesion braking force enhancement braking process of the eddy current brake is determined according to the actual operating conditions of the high-speed train: the single cycle period when the high-speed train is in the initial stage of braking is longer than the single cycle period when the high-speed train is in the later stage of braking.

[0023] As a second aspect of the present invention, an adhesion braking force enhancement system based on an eddy current brake is provided, comprising a train braking control system terminal, an eddy current braking control system and an adhesion braking control system, wherein the adhesion braking force enhancement system further comprises:

[0024] A sensor unit monitors the real-time axle weight of the train and the total vertical suction force of all eddy current brakes on a single train section, and stores the monitoring results in a data processing unit;

[0025] A data processing unit, which calculates the available axle load surplus of a single train section and compares it with the total vertical suction force;

[0026] The control unit adjusts the value of the excitation current in the eddy current brake to reduce the total vertical suction force when the total vertical suction force is greater than the excess axle weight;

[0027] When the total vertical suction force is less than or equal to the axle weight surplus, the data processing unit calculates the available additional adhesion force of a single train section and imports the result into the train braking control system terminal. The train braking control system terminal increases the size of the adhesion braking force based on the available additional adhesion force on the basis of the original adhesion braking force, and transmits the control signal to the adhesion braking control system.

[0028] As a preferred technical solution, the adhesion braking force enhancement system also includes a fault detection unit, which performs fault detection on the eddy current brake when the high-speed train enters the braking condition. If the eddy current brake works normally, it proceeds to the next step; if the eddy current brake fails to work normally, it returns an error message, stops supplying power to all eddy current brakes on the bogie where the faulty eddy current brake is located, and ends the braking of the brake ahead of schedule.

[0029] As a preferred technical solution, the data processing unit calculates the available axle weight surplus of a single train as follows:

[0030] N=4*g*(M0-M)

[0031] Where M0 is the maximum axle weight of the train; M is the real-time axle weight of the train, which is the average axle weight monitored by the sensor unit over a period of time;

[0032] The data processing unit calculates the available additional adhesion of a single train section as follows:

[0033] f=μ*F n

[0034] Where, μ is the maximum adhesion coefficient; F n It is the total vertical suction force of all eddy current brakes in a single train.

[0035] As an optimal technical solution, the cycle period of the adhesion braking force enhancement braking process of the single eddy current brake executed by the adhesion braking force enhancement system is determined according to the actual operating conditions of the high-speed train: the single cycle period when the high-speed train is in the initial stage of braking is longer than the single cycle period when the high-speed train is in the later stage of braking.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1) The adhesion braking force enhancement method based on eddy current brake proposed in the present invention, when the high-speed train implements emergency braking, the linear eddy current brake is fed with excitation current to enter the working state; on the basis of the longitudinal non-adhesion braking force generated by the linear eddy current brake, the linear eddy current braking system calculates the surplus between the maximum axle weight and the actual axle weight to control the excitation current so that the vertical suction force is within a safe range, and at the same time makes full use of the vertical suction force generated by itself, and calculates the increased high-speed train adhesion force available domain in combination with the adhesion coefficient, and feeds the available additional adhesion force back to the adhesion braking system to increase the adhesion braking force and further improve the braking effect of the high-speed train; cooperate with the longitudinal non-adhesion braking force generated by the linear eddy current brake, and then realize the efficient matching and utilization of the braking force and adhesion force under multiple working conditions. The present invention can be applied to any type of linear eddy current brake, and on the basis of the original high-speed train braking system, further improves the total braking force and improves the braking efficiency.

[0038] 2) The method proposed in the present invention can apply the vertical suction force that is not fully utilized in the eddy current brake and add it to the adhesion braking system to improve the adhesion braking force that can be enhanced by the adhesion braking system;

[0039] 3) The method proposed in the present invention can improve the braking effect of the eddy current brake without increasing the excitation current, thereby increasing the energy utilization efficiency of the eddy current brake system;

[0040] 4) The method proposed by the present invention increases the total braking force of the train, improves the braking efficiency, and reduces the braking distance and braking time without changing the total mass of the train;

[0041] 5) The method proposed in the present invention can analyze the axle weight of the train in real time and transmit the data back to the train braking control system. At the same time, it can feedback and adjust the input excitation current, thereby reducing the safety hazards caused by exceeding the axle weight of the train;

[0042] 6) The additional control elements required for the method proposed in the present invention to realize the above functions are simple in structure and easy to connect, and have the advantages of low cost, low failure rate and simple control.

[0043] In summary, the enhancement method of the present invention can effectively improve the braking force of the high-speed train braking system, reduce the train braking distance and braking time, can be reliably applied in the braking system of the high-speed train, and has a simple control structure, clear logic, and is easy to operate and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 The present invention is a flowchart of the method for enhancing the adhesion braking force based on the eddy current brake;

[0045] Figure 2 A schematic diagram of unit linking and data transmission of an embodiment of an adhesion braking force enhancement system based on an eddy current brake of the present invention;

[0046] The numbers in the figure are as follows: 1. Train braking control system terminal; 2. Eddy current braking control system; 3. Adhesion braking control system; 4. Fault detection unit; 5. Control unit; 6. Data processing unit; 7. Sensor unit. DETAILED DESCRIPTION

[0047] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0048] Example 1

[0049] As one embodiment of the present invention, Figure 1 As shown, the present invention provides an implementation process of a method for enhancing adhesion braking force based on an eddy current brake, comprising the following steps:

[0050] Step 1) Integrate the sensor unit, data processing unit, control unit, and fault detection unit required by the enhancement method into the train braking control system, and input the maximum axle weight M0 tons of the train and the maximum adhesion coefficient μ between the wheel and rail of this model of train in advance.

[0051] Step 2) The high-speed train enters the braking condition, an excitation current I is passed into the eddy current brake, the eddy current brake generates electromagnetic force, and begins to realize the braking function.

[0052] Step 3) When the high-speed train enters the braking condition, the fault detection unit performs fault detection on the eddy current brake. If the eddy current brake works normally, the next step is entered; if the eddy current brake fails to work normally, the current is stopped from being supplied to the eddy current brake, an error message is returned, and the braking of the brake is terminated prematurely.

[0053] Step 4) The sensor unit can monitor the train axle weight M tons in real time and feed the data back to the data processing unit.

[0054] Step 5) The data processing unit calculates the difference between the real-time axle weight and the maximum axle weight, M0-M tons, calculates the available axle weight surplus N=4*g*(M0-M) on a single train section, and stores the calculation result.

[0055] Step 6) The sensor unit monitors the total vertical suction force F of all eddy current brakes on a single train n 1000N, and input the result into the data processing unit, and compare it with the axle weight surplus in step 5). If the total vertical suction force is greater than the axle weight surplus, the result is fed back to the control unit, and the total vertical suction force is reduced by adjusting the magnitude of the excitation current in the eddy current brake, and step 6) is repeated; if the total vertical suction force is not greater than the axle weight surplus, proceed to the next step.

[0056] Step 7) The data processing unit calculates the maximum adhesion coefficient and the total vertical suction force as variables to obtain the additional adhesion force available for a single train section f = μ*F n and import the calculation results into the train braking control system.

[0057] Step 8) The train brake control system further increases the adhesion braking force based on the original adhesion braking force, and the value is equal to the available additional adhesion force in step 7).

[0058] Step 9) The real-time running speed of the train is imported into the control unit. If the train speed is not zero, the process returns to step 3); if the train stops, the excitation current to the eddy current brake is stopped, and the braking is ended.

[0059] In the above method flow, the maximum axle weight M0 tons of the train and the maximum adhesion coefficient μ between the wheel and the rail that need to be input in advance are actually calculated in advance according to the type of high-speed train and the relevant accessories used.

[0060] Specifically, the excitation current I provided at the beginning of braking should be consistent with the excitation current before the enhancement method is adopted, and should not interfere with the braking function of the eddy current brake itself.

[0061] Specifically, when the eddy current braking system fails and the eddy current brake cannot work normally, the error information should be promptly fed back to the train braking control system, power supply to all eddy current brakes on the bogie where the faulty eddy current brake is located should be stopped, and other braking methods should be taken in a timely manner.

[0062] Specifically, the sensing unit in step 6) needs to first integrate the total vertical suction of all eddy current brakes in a single train section, and then input it into the data processing unit. The control unit should be connected to the train brake control system, and in the case of non-human operation, the excitation current passed into the eddy current brake can be corrected to control the vertical suction within a safe range.

[0063] Specifically, in step 7), the maximum adhesion coefficient and the total vertical suction are used as variables for calculation, which is specifically performed by multiplying the two values, and the calculation result is the available additional adhesion of the single train.

[0064] Specifically, the single cycle period of step 3) to step 9) should be determined according to the actual operating conditions of the high-speed train. When the high-speed train is in the initial stage of braking and the operating speed is relatively high, combined with the relevant properties of the eddy current brake, the vertical suction force is relatively small, and it is not easy to exceed the axle load surplus range, and the single cycle period can be relatively long; when the high-speed train is in the late stage of braking and the operating speed is relatively low, the vertical suction force of the eddy current brake increases rapidly, which may cause the axle load surplus range to be exceeded, and the single cycle period should be relatively short.

[0065] Specifically, the train axle weight should be taken as the average axle weight over a short period of time, so that the measured data has better stability, in order to avoid the influence of sudden peak value, which may interfere with the calculation of the additional adhesion braking force in the subsequent steps. The sampling time should not exceed the single cycle period of step 3) to step 9).

[0066] Specifically, in step 9), the train is stopped, that is, the train speed is reduced to 0. At this time, the high-speed train is completely stopped, and the control unit stops supplying excitation current to the eddy current brake by sending a control signal to the train brake control system.

[0067] Example 2

[0068] As another implementation of the present invention, this embodiment also provides a train braking control system that uses the adhesion braking force enhancement method based on the eddy current brake as described above.

[0069] like Figure 2 The figure shows a schematic diagram of unit linking and data transmission of an embodiment of the control system of the present invention. The dashed box shows examples of components required to implement the adhesion braking force enhancement method and their data transmission methods. The required components include a fault detection unit 4, a control unit 5, a data processing unit 6, and a sensor unit 7. When the high-speed train enters the braking condition, the train braking control system terminal 1 outputs a braking command, the eddy current braking control system 2 and the adhesion braking control system 3 work, and transmit the braking command to the eddy current brake and the adhesion brake respectively. At this time, the eddy current braking control system 2 first transmits the control signal to the fault detection unit 4, and the fault detection unit 4 detects whether the eddy current brake is working normally, and transmits the detection result back to the eddy current braking control system 2. If no fault occurs, the eddy current braking control system 2 transmits the start sampling signal to the sensor unit 7 through the control unit 5. At this time, the sensor unit 7 starts to collect the required data, including the real-time axle weight M of the train and the total vertical suction force F of the eddy current brake. nThe sampling result is stored in the data processing unit 6. After that, the data processing unit 6 starts to calculate the available axle weight surplus N = 4*g*(M0-M) of the single train and stores the calculation result. After that, the data processing unit 6 compares the axle weight surplus N with the total vertical suction N. If the axle weight surplus N is less than the total vertical suction F n , the data processing unit 6 returns the result to the control unit 5 and adjusts the value of the excitation current I; otherwise, the data processing unit 6 combines the result with the adhesion coefficient μ to calculate the additional adhesion force available for the single train section f=μ*F n The result is imported into the train brake control system terminal 1, and finally the control signal is transmitted to the adhesion brake control system 3 to complete a control cycle.

[0070] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A method for enhancing adhesion braking force based on eddy current brake, characterized in that: The following steps are performed for a high-speed train including an eddy current brake control system (2) and an adhesion brake control system (3): Obtain the maximum axle weight of the train and the maximum adhesion coefficient between the wheel and rail; When the high-speed train enters a braking condition, an excitation current is introduced into the eddy current brake through the eddy current braking control system (2) to perform braking; Monitor train axle weight in real time and calculate the available axle weight surplus on a single train based on the real-time axle weight and the maximum axle weight; Monitor the total vertical suction force of all eddy current brakes on a single train section, and compare the monitoring result with the available axle weight surplus of the train section. If the total vertical suction force is greater than the axle weight surplus, adjust the magnitude of the excitation current in the eddy current brake to reduce the total vertical suction force until the total vertical suction force is less than or equal to the axle weight surplus. The available additional adhesion of a single train is calculated based on the maximum adhesion coefficient and the total vertical suction force; By using the adhesion braking control system (3), the adhesion braking force is further increased based on the available additional adhesion force on the basis of the original adhesion braking force; The above-mentioned adhesion braking force enhancement braking process based on the eddy current brake is cyclically executed until the train stops, and the excitation current to the eddy current brake is stopped, thereby ending the braking.

2. The method for enhancing the adhesion braking force based on the eddy current brake according to claim 1, characterized in that: The method performs fault detection on the eddy current brake when the high-speed train enters a braking condition, and proceeds to the next step if the eddy current brake works normally; if the eddy current brake fails to work normally, an error message is returned, power supply to all eddy current brakes on the bogie where the faulty eddy current brake is located is stopped to terminate the braking of the brake in advance, and other braking methods are adopted.

3. The method for enhancing the adhesion braking force based on the eddy current brake according to claim 1, characterized in that: The available axle weight surplus of a single train is calculated as follows: N=4*g*(M0-M) Where M0 is the maximum axle weight of the train; M is the real-time axle weight of the train.

4. The method for enhancing the adhesion braking force based on the eddy current brake according to claim 3, characterized in that: The real-time axle weight of the train is the average axle weight monitored in real time over a period of time.

5. The method for enhancing the adhesion braking force based on the eddy current brake according to claim 1, characterized in that: The additional adhesion of the single train can be calculated as follows: f=μ*F n Where, μ is the maximum adhesion coefficient; F n It is the total vertical suction force of all eddy current brakes in a single train.

6. The method for enhancing adhesion braking force based on eddy current brake according to claim 1, characterized in that: The single cycle period of the adhesion braking force enhancement braking process of the eddy current brake is determined according to the actual operating conditions of the high-speed train: the single cycle period when the high-speed train is in the initial stage of braking is longer than the single cycle period when the high-speed train is in the later stage of braking.

7. An adhesion braking force enhancement system based on an eddy current brake, comprising a train braking control system terminal (1), an eddy current braking control system (2) and an adhesion braking control system (3), characterized in that: The adhesion braking force enhancement system further comprises: A sensor unit (7) monitors the real-time axle weight of the train and the total vertical suction force of all eddy current brakes on a single train section, and stores the monitoring results in a data processing unit (6); A data processing unit (6) calculates the available axle weight surplus of a single train section and compares it with the total vertical suction force; The control unit (5) adjusts the value of the excitation current in the eddy current brake to reduce the total vertical suction force when the total vertical suction force is greater than the excess axle weight; When the total vertical suction force is less than or equal to the axle weight surplus, the data processing unit (6) calculates the available additional adhesion force of a single train section and imports the result into the train brake control system terminal (1). The train brake control system terminal (1) increases the magnitude of the adhesion braking force based on the available additional adhesion force on the basis of the original adhesion braking force and transmits a control signal to the adhesion braking control system (3).

8. The adhesion braking force enhancement system based on eddy current brake according to claim 7, characterized in that: The adhesion braking force enhancement system also includes a fault detection unit (4), which performs fault detection on the eddy current brake when the high-speed train enters a braking condition, and if the eddy current brake works normally, proceeds to the next step; if the eddy current brake fails to work normally, an error message is returned, and power supply to all eddy current brakes on the bogie where the faulty eddy current brake is located is stopped to terminate the braking of the brake in advance.

9. The adhesion braking force enhancement system based on eddy current brake according to claim 7, characterized in that: The data processing unit (6) calculates the available axle weight surplus of a single train as follows: N=4*g*(M0-M) Where M0 is the maximum axle weight of the train; M is the real-time axle weight of the train, which is the average axle weight monitored by the sensor unit (7) over a period of time; The data processing unit (6) calculates the available additional adhesion of a single train section as follows: f=μ*F n Where, μ is the maximum adhesion coefficient; F n It is the total vertical suction force of all eddy current brakes in a single train.

10. The adhesion braking force enhancement system based on eddy current brake according to claim 7, characterized in that: The cycle period of the adhesion braking force enhancement braking process of the single eddy current brake executed by the adhesion braking force enhancement system is determined according to the actual operating conditions of the high-speed train: the single cycle period when the high-speed train is in the initial stage of braking is longer than the single cycle period when the high-speed train is in the later stage of braking.

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