A virtual marshalling-based electric-pneumatic hybrid brake control method and device

Abstract

The application provides a virtual marshalling-based electric air hybrid brake control method and device, and relates to the technical field of locomotive trains. The method comprises the following steps: acquiring a speed point corresponding to a sending electric brake decay signal time of a current brake level; if it is determined that the current train speed is equal to the speed point, sending an air brake force corresponding to the current brake level to a BCU, and sending an electric brake decay signal to a TCU when a delay duration reaches a lag time, so as to start controlling the electric brake force to decrease to zero through the TCU; and controlling the speed of increasing the air brake force according to the current brake level, a first variable slope and a second variable slope at an initial time point when the air brake force starts to increase. The device executes the above method. The virtual marshalling-based electric air hybrid brake control method and device provided in the application can improve the train stopping precision.

Description

Technical Field

[0001] This invention relates to the field of locomotive and train technology, and specifically to an electro-pneumatic hybrid braking control method and device based on virtual train formation. Background Technology

[0002] Vehicle braking is classified into electric braking and friction braking according to the implementing equipment. Electric braking is implemented by the traction system (TCU), while friction braking is implemented by the braking system (BCU). Braking is also classified into service braking and emergency braking according to function. Emergency braking uses pure friction braking and is directly controlled by the emergency braking safety circuit. When the emergency braking safety circuit loses power, all vehicles in the train simultaneously apply emergency braking. Service braking uses a deceleration control mode. The braking system calculates the target braking force based on the deceleration command sent by the signaling system and the vehicle load. Service braking is usually completed by a combination of electric braking and friction braking.

[0003] Hybrid braking employs a hybrid braking method that coordinates electric braking and friction braking in real time, prioritizing electric braking and delaying the activation of friction braking. Data exchange between the BCU and TCU is handled by the Train Control and Diagnostic System (TCMS).

[0004] Previous control strategies would send an electric brake fade signal as soon as the speed reached a fixed value, regardless of the braking level, to initiate friction braking force replenishment. After a delay, the electric brakes would begin to fade. This new control strategy compensates for the lag in friction braking force by sending an electric brake fade signal to the braking system in advance. Based on the lowest speed value V0 at which 100% of the commonly used electric braking force fades to 0, the speed value V1 before the transition point (ΔT0 time) is calculated. Regardless of the braking level at that time, the control method follows the principle that air braking force begins to increase after detecting the V1 speed value, and electric brakes begin to fade after ΔT0 time. Figure 1 As shown.

[0005] The biggest problem with this control strategy is that while it can ensure stable instantaneous deceleration when switching between electric and friction braking forces under 100% electric braking force, in virtual train formation mode, higher control precision is required because both trains need to enter the platform simultaneously. The dual-train system generally adopts MPC control, which requires the train to have a stable kinematic model. Furthermore, the signaling system controls braking force based on the distance to the platform, and the required braking force varies. This means that electric braking does not begin to decay at 100% braking force. When the braking level decreases, the speed at which electric braking finally reaches zero will be higher than the speed at 100% electric braking force, causing air braking to intervene prematurely in the stopping process. Because the friction coefficient of mechanical braking varies with the magnitude of braking force and speed at different speeds, there is a certain deviation between the friction braking force and the required braking force. This causes the signaling system to adjust braking commands at the transition between low-speed electric braking and friction braking, resulting in insufficient stopping accuracy and affecting train operation.

[0006] At low speeds, the friction coefficient of the brake shoes or brake pads made of synthetic materials increases (Appendix F of the UIC541-4 standard provides a curve showing the change in the friction coefficient of synthetic material brake shoes with speed). Figure 2 As shown, when the force F acting on the brake shoe or brake pad remains constant, according to the friction force formula f = μF, the actual braking force f acting on the vehicle will also increase at low speeds, and the train's deceleration will also increase.

[0007] like Figure 1 As shown, previous control strategies involved friction braking force initially supplementing at a fixed slope, while electric braking began to decline at the same slope, ensuring that the train's deceleration 'a' remained constant during electro-pneumatic switching. However, due to the characteristics of the composite material brake shoes and pads, the train could not achieve a relatively constant ideal deceleration, such as... Figure 3 As shown, when the friction braking force is greater than the required braking force, the signal system will reduce the required braking force. There is a certain time required for the air brakes to adjust the braking force and for the deceleration to react, but by this time the vehicle is already close to stopping, often resulting in insufficient stopping precision and affecting vehicle operation.

[0008] Reducing the upward slope of the air brake, thus delaying the time when deceleration increases and decreasing the train speed when deceleration increases, helps mitigate the impact of changes in the friction coefficient. However, the reduced braking force due to the return spring force of the friction brake cylinder, and the lag in friction braking caused by the brake cylinder's strut stroke, result in a longer control response time and lag in the friction braking force itself. If the upward slope of the air brake is further reduced at this point, the lag in the air brake force will decrease the total braking force and deceleration, also causing the signal system to adjust its level, leading to insufficient stopping accuracy and affecting train operation. Figure 4As shown. Moreover, under different loads, the change in braking force and the fixed value of the electric braking delay time ΔT0 will result in uneven deceleration under different loads. Summary of the Invention

[0009] To address the problems in the prior art, embodiments of the present invention provide an electro-pneumatic hybrid braking control method and apparatus based on virtual grouping, which can at least partially solve the problems existing in the prior art.

[0010] On the one hand, this invention proposes an electro-pneumatic hybrid braking control method based on virtual train formation, comprising:

[0011] Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated.

[0012] If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero.

[0013] At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope.

[0014] The step of calculating the speed point at which the electric brake fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, includes:

[0015] The velocity point is calculated using the following formula:

[0016] Vb_y=Vb+k×(Vc_x-Vb+a×ΔT);

[0017] Wherein, Vb_y is the speed point, Vb is the minimum speed point, k is the current braking level, Vc_x is the actual electric braking force descent speed point corresponding to the maximum braking level, a is the deceleration when the current braking level is the maximum braking level, and ΔT is the lag time.

[0018] Determining the first variable slope includes:

[0019] The first variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the initial time point at which the air braking force begins to rise, and the first rise time point.

[0020] The first rise time point is the moment when the air braking force reaches the product of the preset braking level value and the maximum air braking force.

[0021] Determining the second variable slope includes:

[0022] The second variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the first rise time point and the second rise time point when the air braking force begins to rise;

[0023] The second rise time point is the moment when the air braking force reaches the maximum air braking force.

[0024] Wherein, the step of controlling the rate of increase of air braking force at the initial time point when the air braking force begins to rise, based on the current braking level, the first variable slope, and the second variable slope, includes:

[0025] If it is determined that the current braking level is less than the preset braking level value, the speed at which the air braking force is increased is controlled by the first variable slope.

[0026] The step of controlling the rate at which the air braking force is increased based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise further includes:

[0027] If it is determined that the current braking level is greater than the preset braking level value, the speed of increasing the air braking force is controlled by the first variable slope until the speed of the air braking force reaches the product of the preset braking level value and the maximum air braking force.

[0028] The air braking force is continuously increased by the second variable slope control until it reaches the maximum air braking force value.

[0029] On one hand, the present invention proposes an electro-pneumatic hybrid braking control device based on virtual formation, comprising:

[0030] The calculation unit is used to calculate the speed point when the electric braking fade signal is sent, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force.

[0031] The transmitting unit is configured to send the air braking force corresponding to the current braking level to the BCU if it is determined that the current train speed is equal to the speed point, and send the electric braking fade signal to the TCU when the delay time reaches the lag time, so as to start controlling the reduction of the electric braking force to zero through the TCU.

[0032] The control unit is configured to control the rate at which the air braking force is increased based on the current braking level, a first variable slope, and a second variable slope at the initial time point when the air braking force begins to rise.

[0033] In another aspect, embodiments of the present invention provide a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the following method:

[0034] Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated.

[0035] If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero.

[0036] At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope.

[0037] This invention provides a computer-readable storage medium, comprising:

[0038] The computer-readable storage medium stores a computer program that, when executed by a processor, implements the following method:

[0039] Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated.

[0040] If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero.

[0041] At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope.

[0042] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the following method:

[0043] Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated.

[0044] If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero.

[0045] At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope.

[0046] The electro-pneumatic hybrid braking control method and apparatus based on virtual train formation provided in this invention calculates the speed point at which the electric braking fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time for compensating for friction braking force. If the current train speed is determined to be equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start controlling the reduction of the electric braking force until it reaches zero. At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope, which can improve the train stopping accuracy. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0048] Figure 1This is a schematic diagram illustrating the electro-pneumatic switching control logic provided by existing technology.

[0049] Figure 2 This is a schematic diagram illustrating how changes in the coefficient of friction at different speeds lead to changes in deceleration, provided by existing technology.

[0050] Figure 3 This is a schematic diagram illustrating how the increased friction coefficient at low speeds leads to increased deceleration, as provided by existing technology.

[0051] Figure 4 This is a schematic diagram illustrating how reducing the air brake output slope leads to a smaller deceleration, provided by existing technology.

[0052] Figure 5 This is a schematic diagram illustrating the hybrid braking control logic provided in an embodiment of the present invention.

[0053] Figure 6 This is a flowchart illustrating an embodiment of the electro-pneumatic hybrid braking control method based on virtual grouping provided by the present invention.

[0054] Figure 7 This is a schematic diagram illustrating the speed point when calculating and sending the electric braking fade signal according to an embodiment of the present invention.

[0055] Figure 8 This is a schematic diagram illustrating the control of the variable switching point provided in an embodiment of the present invention.

[0056] Figure 9 This is a schematic diagram illustrating the braking force output control slope when the load changes, provided in an embodiment of the present invention.

[0057] Figure 10 This is a schematic diagram illustrating the control of braking force output when the level is less than k0, provided in an embodiment of the present invention.

[0058] Figure 11 This is a schematic diagram illustrating the control of braking force output when the level is greater than k0, provided in an embodiment of the present invention.

[0059] Figure 12 This is a schematic diagram illustrating the variable air braking force rise slope control provided in an embodiment of the present invention.

[0060] Figure 13 This is a schematic diagram of the structure of an electro-pneumatic hybrid braking control device based on virtual grouping provided in an embodiment of the present invention.

[0061] Figure 14 This is a schematic diagram of the physical structure of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0062] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be arbitrarily combined with each other.

[0063] like Figure 5 The hybrid braking control logic is explained as follows:

[0064] Wherein, t0: When the train BCU receives the braking command, it calculates the total braking force required by the train. At the same time, the TCU calculates the electric braking force (electric braking capacity value) that can be exerted and sends the electric braking capacity value to the BCU. The BCU uses the electric braking capacity value sent by the TCU to subtract the total braking force from the electric braking capacity value to obtain the air braking force that can be used for supplementation.

[0065] Among them, t0-t1: there is no need to replenish the above-mentioned air braking force during this time period, and the air braking force can be replenished after time t1 ends.

[0066] In the time interval t2-t3: At time t2, the air braking force (brake cylinder pressure) begins to rise. After a delay of ΔT (ΔT = t3 - t2), an electric brake fade signal is sent at time t3. Upon receiving the electric brake fade signal, the traction system begins to reduce the electric braking force. The speed point corresponding to time t2 varies depending on the braking level, which will be explained further in a later section.

[0067] Among them, t3-t4: the electric brake fades at a certain slope (i.e., the traction fade slope), and fades to 0 when the speed reaches a certain speed. The braking system supplements the air braking force with a variable slope according to the braking command. The specific method of changing the slope will be further explained in the following section.

[0068] Among them, t4: the holding brake application command becomes high level, the traction command is invalid, and the BCU applies the holding brake.

[0069] Among them, t5: the braking command is 0, and the electric braking capability value sent by the TCU becomes 0.

[0070] Among them, t6: when the brake release command becomes high, the traction command is valid and there is no braking command, the BCU releases the brake, and the train enters the traction process.

[0071] Among them, at times t2-t4, the electric braking fade speed point when the braking level is k (0-100%) can be inferred from the speed when the electric braking fades to 0, the fade speed point when the maximum braking level k (k=100%), and the lag time ΔT of the compensating friction braking force.

[0072] Figure 6 This is a flowchart illustrating an embodiment of the electro-pneumatic hybrid braking control method based on virtual train formation provided by the present invention, as shown below. Figure 6 As shown, the electro-pneumatic hybrid braking control method based on virtual formation provided in this embodiment of the invention includes:

[0073] Step S1: Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, calculate the speed point when the electric braking fade signal is sent corresponding to the current braking level.

[0074] Step S2: If it is determined that the current train speed is equal to the speed point, then send the air braking force corresponding to the current braking level to the BCU, and send the electric braking fade signal to the TCU when the delay time reaches the lag time, so that the TCU can start controlling the reduction of the electric braking force until it is zero.

[0075] Step S3: At the initial time point when the air braking force begins to rise, control the speed at which the air braking force is increased according to the current braking level, the first variable slope, and the second variable slope.

[0076] In step S1 above, the device calculates the speed point at which the electric brake fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force. The device can be a computer device executing this method, specifically a Train Control and Diagnostic System (TCMS). The acquisition, storage, use, and processing of data in this application's technical solution all comply with relevant regulations. The calculation of the speed point at which the electric brake fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, includes:

[0077] The velocity point is calculated using the following formula:

[0078] Vb_y=Vb+k×(Vc_x-Vb+a×ΔT);

[0079] Wherein, Vb_y is the speed point, Vb is the minimum speed point, k is the current braking level, Vc_x is the actual electric braking force descent speed point corresponding to the maximum braking level, a is the deceleration when the current braking level is the maximum braking level, and ΔT is the lag time.

[0080] like Figure 7 As shown, the explanation is as follows:

[0081] When the level changes, the decay speed point can be postponed from the original Vb_x decay speed point to the Vb_y decay speed point, ensuring that the speed at which the electric braking force decays to 0 is the lowest speed value Vb that the traction system can achieve.

[0082] Where: Vb is the lowest speed point when the actual electric braking force reaches zero;

[0083] ΔT is the lag time for compensating for friction braking force, which can be calculated using existing methods;

[0084] Vb_x is the speed point at which the electric braking fade signal is sent, corresponding to the maximum braking level (k = 100%); Vc_x is the actual electric braking force reduction speed point corresponding to the maximum braking level (k = 100%).

[0085] Vb_y is the speed point at which the electric braking fade signal is sent corresponding to the current braking level, and Vc_y is the actual electric braking force reduction speed point corresponding to the current braking level.

[0086] When the braking level is k, the formula for the electric braking fade speed point is:

[0087] Vb_y=Vb+k×(Vc_x-Vb+a×ΔT);

[0088] Depend on Figure 7 As shown, the speed at which the electric braking fade signal is issued during maximum service braking is:

[0089] Vb_x = Vc_x + a × ΔT, therefore, substituting into the above formula, we know that Vb_y = Vb + k × (Vb_x - Vb). This formula does not need to consider the effects of deceleration and electric braking control slope, which greatly simplifies the formula and meets the needs of engineering applications.

[0090] In step S2 above, if the device determines that the current train speed is equal to the speed point, it sends the air braking force corresponding to the current braking level to the BCU, and sends the electric brake fade signal to the TCU when the delay time reaches the hysteresis time, so that the TCU can start controlling the reduction of the electric braking force until it is zero. Figure 8As shown, based on the braking level k sent by the signal system or brake handle, the speed Vb when the electric brake fades to 0, the fade speed point Vb_x at the maximum braking level k (k = 100%), the lag time ΔT for compensating for friction braking force, and the collected deceleration a at the current level, the electric brake fade speed point Vb_y is deduced. At this time, the continuously decreasing train speed V is detected. When V decreases to be equal to Vb_y, the braking system (BCU) is notified to start applying the air braking force corresponding to level k. After a delay of ΔT, the electric brake fade signal is sent to the traction system (TCU), and the TCU begins to reduce the electric braking force until it reaches 0.

[0091] It can also change the air brake rise slope, collect signals such as train weight and braking level in real time, and control the BCU to apply air braking force according to different slopes.

[0092] In step S3 above, the device controls the rate at which the air braking force increases based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise.

[0093] Determining the first variable slope includes:

[0094] The first variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the initial time point at which the air braking force begins to rise, and the first rise time point.

[0095] The first rise time point is the moment when the air braking force reaches the product of the preset braking level value and the maximum air braking force.

[0096] The calculation of the first variable slope based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the initial time point at which the air braking force begins to rise, and the first rise time point includes:

[0097] The first variable slope δ is calculated using the following formula. 1m :

[0098] δ 1m =k0×f m / (t3-t2);

[0099] Where k0 is the preset braking level value, f m The maximum air braking force corresponds to the maximum braking level. t2 is the initial time point at which the air braking force begins to rise, and t3 is the first time point at which the air braking force begins to rise. k0 is a fixed percentage (0-100%), which needs to be determined based on the actual situation of the brake cylinder. f mThe braking force is at 100% of its maximum capacity and varies with the vehicle's load.

[0100] f m =m×a;

[0101] Where m is the current load of the train, and a can be referred to the above explanation, which will not be repeated here.

[0102] Determining the second variable slope includes:

[0103] The second variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the first rise time point and the second rise time point when the air braking force begins to rise;

[0104] The second rise time point is the moment when the air braking force reaches the maximum air braking force.

[0105] The calculation of the second variable slope based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the first rise time point and the second rise time point when the air braking force begins to rise includes:

[0106] The second variable slope δ is calculated using the following formula. 2m :

[0107] δ 2m =(f m -k0×f m ) / (t4-t3);

[0108] f m =m×a;

[0109] Where m represents the current load of the train. a is explained above and will not be repeated here.

[0110] Wherein, t4 is the second rise time point at which the air braking force begins to rise, and other parameters can be referred to the above description.

[0111] like Figure 9 As shown, the braking force is also affected by the load, therefore f m The rate of deceleration will increase with the load. To ensure a rapid increase in deceleration, it needs to increase at a slope δ within the time interval t2-t3. 1m Increase the air braking force to k0×f m If we want to delay the time when the deceleration increases and reduce the train speed when the deceleration increases, we need to move the train at a slope δ during the time interval t3-t4. 2m Increase the air braking force to f m .like Figure 9 As shown, δ 1m The curve with the slope will fall within the range of ①, δ2m The curve with the slope will fall within the range of ②.

[0112] The step of controlling the rate at which the air braking force is increased based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise includes:

[0113] If it is determined that the current braking level is less than the preset braking level value, the speed at which the air braking force is increased is controlled by the first variable slope.

[0114] The method of controlling the rate at which the air braking force is increased based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise further includes:

[0115] If it is determined that the current braking level is greater than the preset braking level value, the speed of increasing the air braking force is controlled by the first variable slope until the speed of the air braking force reaches the product of the preset braking level value and the maximum air braking force.

[0116] The air braking force is continuously increased by the second variable slope control until it reaches the maximum air braking force value.

[0117] like Figure 10 As shown, during the switching between hybrid braking and electro-pneumatic systems, if the level is less than or equal to k0 (0-100%), a slope δ greater than the traction fade slope is applied. 1m To control the increase of braking force and prevent the decrease in deceleration caused by the long response time and lag characteristic of friction braking due to the return spring force of the brake cylinder and the stroke of the brake cylinder strut. Figure 4 (The situation).

[0118] like Figure 11 As shown, if the braking force is greater than or equal to k0 (0-100%), the braking force increases to the level corresponding to k0 × f. m Previously, according to a slope δ greater than the traction decay slope. 1m To control the increase of braking force and prevent the decrease in deceleration caused by the long response time and lag characteristic of friction braking due to the return spring force of the brake cylinder and the stroke of the brake cylinder strut. Figure 4 (The situation where the braking force increases to k0 corresponds to a braking force of k0×f). m Then, according to a slope δ that is smaller than the traction decay slope. 2m Controlling the increase in braking force, delaying the time when deceleration increases, and reducing the train speed when deceleration increases helps to reduce the impact of changes in the coefficient of friction. Figure 3 (The situation).

[0119] This invention can provide different electric brake fade speed points according to different levels, ensuring that the speed at which the electric braking force fades to 0 is the lowest speed value that the traction system can achieve. Regardless of the level, the speed point at which the electric brake fades to 0 remains unchanged, making full use of electric braking to stop the vehicle, delaying the speed point at which the air brake intervenes in the vehicle stopping process, and reducing the impact of the deviation between the friction braking force and the required braking force.

[0120] Changing the slope of the air braking force's ascent allows for supplementing air braking force at a slope greater than the electric braking force decay slope during the initial stage of electro-pneumatic switching. This prevents the deceleration decrease caused by the long response time and lag characteristic of friction braking due to the return spring force and brake cylinder strut stroke. In the later stage of electro-pneumatic switching, air braking force can be supplemented at a slope less than the electric braking force decay slope, delaying the time when deceleration increases and reducing the train speed when deceleration increases, thus helping to mitigate the impact of changes in the friction coefficient. Furthermore, the braking force slope δ... 1m and δ 2m The deceleration rate varies depending on the load to prevent deceleration fluctuations caused by a fixed electric braking delay time ΔT0, ensuring smooth deceleration under different loads. Furthermore, a level parameter k0 is defined; when the level is below k0, a single slope δ is used. 1m To control this, the double slope δ is only used when the level is higher than k0. 1m and δ 2m This is used to control and ensure the deceleration control requirements at different levels.

[0121] This invention not only maximizes the use of electric braking force, but also eliminates the effects of air braking lag and increased friction coefficient at low speeds, enabling the signal system to maintain the braking level unchanged when switching between electric braking and friction braking, thereby improving parking accuracy and ensuring normal vehicle operation.

[0122] like Figure 12 As shown, based on the brake level k sent by the signal system or brake lever, the current vehicle load, and the brake cylinder characteristic parameters (preset brake level value) k0 (between 0-100%), the slope δ of the air brake increase is derived. 1m and δ 2m When the level k is lower than k0, a single slope δ is used. 1m To control this, a double slope δ is used only when the level is higher than k0. 1m After increasing the air braking force to k0*fm, according to the slope δ 2m To control the remaining air braking force.

[0123] By specifying different electric brake fade speed points based on different braking levels, it can be ensured that the speed at which the electric braking force fades to zero is the lowest speed achievable by the traction system. Regardless of the braking level, the speed point at which the electric brake fades to zero remains unchanged, fully utilizing electric braking for stopping and delaying the speed point at which air braking intervenes in the vehicle's stopping process. This reduces the impact of deviations between friction braking force and the required braking force. In the initial stage of the hybrid braking electro-pneumatic transition, supplementing air braking force with a slope greater than the electric braking force fade slope prevents the deceleration decrease caused by the long response time and lag characteristic of friction braking due to the return spring force and brake cylinder strut stroke. In the later stage of the electro-pneumatic transition, supplementing air braking force with a slope less than the electric braking force fade slope delays the time when deceleration increases, reducing the train speed when deceleration increases, and helping to mitigate the impact of changes in the friction coefficient. This ensures that the signal system maintains a constant braking level at the transition between low-speed electric braking and friction braking, improving stopping accuracy and ensuring normal vehicle operation.

[0124] The electro-pneumatic hybrid braking control method based on virtual train formation provided in this invention calculates the speed point at which the electric braking fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time for compensating for friction braking force. If the current train speed is determined to be equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start controlling the reduction of the electric braking force until it reaches zero. At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope, which can improve the train stopping accuracy.

[0125] Further, the step of calculating the speed point at which the electric braking fade signal is sent corresponding to the current braking level based on the train's current braking level and its deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force includes:

[0126] The velocity point is calculated using the following formula:

[0127] Vb_y=Vb+k×(Vc_x-Vb+a×ΔT);

[0128] Wherein, Vb_y is the speed point, Vb is the minimum speed point, k is the current braking level, Vc_x is the actual electric braking force descent speed point corresponding to the maximum braking level, a is the deceleration when the current braking level is the maximum braking level, and ΔT is the lag time. Refer to the above embodiments for further explanation; no further details will be provided.

[0129] Further, determining the first variable slope includes:

[0130] The first variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the initial time point at which the air braking force begins to rise, and the first rise time point; this can be referred to the above embodiment for explanation, and will not be repeated here.

[0131] The first rise time point is the moment when the air braking force reaches the product of the preset braking level and the maximum air braking force. This can be referred to the above embodiment for further explanation, and will not be repeated here.

[0132] Further, determining the second variable slope includes:

[0133] The second variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the first rise time point and the second rise time point when the air braking force begins to rise; this can be referred to the above embodiment for explanation, and will not be repeated here.

[0134] The second ascent time point is the moment when the air braking force reaches the maximum air braking force. This can be referred to the above embodiment for further explanation, and will not be repeated here.

[0135] Further, the step of controlling the rate of increase of the air braking force at the initial time point when the air braking force begins to rise, based on the current braking level, the first variable slope, and the second variable slope, includes:

[0136] If it is determined that the current braking level is less than the preset braking level value, the speed at which the air braking force is increased is controlled by the first variable slope. This can be referred to the above embodiment for further explanation, and will not be repeated here.

[0137] Furthermore, the step of controlling the rate of increase of the air braking force based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise also includes:

[0138] If it is determined that the current braking level is greater than the preset braking level value, the speed of increasing the air braking force is controlled by the first variable slope until the speed of the air braking force reaches the product of the preset braking level value and the maximum air braking force; this can be referred to the above embodiment for explanation, and will not be repeated here.

[0139] The air braking force is continuously increased by the second variable slope control until it reaches the maximum air braking force value. This can be referred to the above embodiment for explanation, and will not be repeated here.

[0140] Figure 13 This is a schematic diagram of the structure of an electro-pneumatic hybrid braking control device based on virtual train formation provided in an embodiment of the present invention, as shown below. Figure 13 As shown, the electro-pneumatic hybrid braking control device based on virtual grouping provided in this embodiment of the invention includes a computing unit 1301, a transmitting unit 1302, and a control unit 1303, wherein:

[0141] The calculation unit 1301 is used to calculate the speed point at which the electric braking fade signal is sent corresponding to the current braking level based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensation friction braking force. The sending unit 1302 is used to send the air braking force corresponding to the current braking level to the BCU if it is determined that the current train speed is equal to the speed point, and send the electric braking fade signal to the TCU when the delay time reaches the lag time, so that the TCU can start controlling the reduction of the electric braking force until it is zero. The control unit 1303 is used to control the speed at which the air braking force is increased based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise.

[0142] Specifically, the calculation unit 1301 in the device is used to calculate the speed point at which the electric braking fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensation friction braking force; the sending unit 1302 is used to send the air braking force corresponding to the current braking level to the BCU if it is determined that the current train speed is equal to the speed point, and to send the electric braking fade signal to the TCU when the delay time reaches the lag time, so that the TCU can start controlling the reduction of the electric braking force until it is zero; the control unit 1303 is used to control the speed of increasing the air braking force according to the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise.

[0143] The electro-pneumatic hybrid braking control device based on virtual train formation provided in this embodiment of the invention calculates the speed point at which the electric braking force fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time for compensating for friction braking force. If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start controlling the reduction of the electric braking force until it is zero. At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope, which can improve the train stopping accuracy.

[0144] The embodiments of the present invention provide an electro-pneumatic hybrid braking control device based on virtual grouping, which can be used to execute the processing flow of the above-described method embodiments. Its functions will not be repeated here, but can be referred to the detailed description of the above-described method embodiments.

[0145] Figure 14 This is a schematic diagram of the physical structure of a computer device provided in an embodiment of the present invention, such as... Figure 14 As shown, the computer device includes: a memory 1401, a processor 1402, and a computer program stored in the memory 1401 and executable on the processor 1402. When the processor 1402 executes the computer program, it implements the following method:

[0146] Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated.

[0147] If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero.

[0148] At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope.

[0149] This embodiment discloses a computer program product, which includes a computer program that, when executed by a processor, implements the following method:

[0150] Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated.

[0151] If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero.

[0152] At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope.

[0153] This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the following method:

[0154] Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated.

[0155] If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero.

[0156] At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope.

[0157] Compared with existing technical solutions, the electro-pneumatic hybrid braking control method based on virtual train formation provided by this invention calculates the speed point at which the electric braking fade signal is sent corresponding to the current braking level, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time for compensating for friction braking force. If the current train speed is determined to be equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start controlling the reduction of the electric braking force until it is zero. At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope, which can improve the train stopping accuracy.

[0158] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0159] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0160] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0161] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0162] In the description of this specification, the references to terms such as "an embodiment," "a specific embodiment," "some embodiments," "for example," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0163] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A hybrid electro-pneumatic braking control method based on virtual train formation, characterized in that, include: Based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, the speed point at which the electric braking fade signal is sent corresponding to the current braking level is calculated. If it is determined that the current train speed is equal to the speed point, the air braking force corresponding to the current braking level is sent to the BCU, and the electric braking fade signal is sent to the TCU when the delay time reaches the lag time, so that the TCU can start to control the reduction of the electric braking force until it is zero. At the initial time point when the air braking force begins to rise, the speed at which the air braking force is increased is controlled according to the current braking level, the first variable slope, and the second variable slope. Determining the first variable slope includes: The first variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the initial time point at which the air braking force begins to rise, and the first rise time point. The first rise time point is the moment when the air braking force reaches the product of the preset braking level value and the maximum air braking force.

2. The electro-pneumatic hybrid braking control method based on virtual train formation according to claim 1, characterized in that, The calculation of the speed point at which the electric brake fade signal is sent, corresponding to the current braking level and its deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force, includes: The velocity point is calculated using the following formula: Vb_y=Vb+k×(Vc_x - Vb+a×ΔT); Wherein, Vb_y is the speed point, Vb is the minimum speed point, k is the current braking level, Vc_x is the actual electric braking force descent speed point corresponding to the maximum braking level, a is the deceleration when the current braking level is the maximum braking level, and ΔT is the lag time.

3. The electro-pneumatic hybrid braking control method based on virtual train formation according to claim 1, characterized in that, Determining the second variable slope includes: The second variable slope is calculated based on the preset braking level value, the maximum air braking force corresponding to the maximum braking level, the first rise time point and the second rise time point when the air braking force begins to rise; The second rise time point is the moment when the air braking force reaches the maximum air braking force.

4. The electro-pneumatic hybrid braking control method based on virtual train formation according to claim 3, characterized in that, The step of controlling the rate at which the air braking force is increased based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise includes: If it is determined that the current braking level is less than the preset braking level value, the speed at which the air braking force is increased is controlled by the first variable slope.

5. The electro-pneumatic hybrid braking control method based on virtual train formation according to claim 4, characterized in that, The method of controlling the rate at which the air braking force is increased based on the current braking level, the first variable slope, and the second variable slope at the initial time point when the air braking force begins to rise further includes: If it is determined that the current braking level is greater than the preset braking level value, the speed of increasing the air braking force is controlled by the first variable slope until the speed of the air braking force reaches the product of the preset braking level value and the maximum air braking force. The air braking force is continuously increased by the second variable slope control until it reaches the maximum air braking force value.

6. A hybrid electro-pneumatic braking control device based on virtual train formation, characterized in that, include: The calculation unit is used to calculate the speed point when the electric braking fade signal is sent, based on the train's current braking level and deceleration, the actual electric braking force descent speed point corresponding to the maximum braking level, the lowest speed point when the actual electric braking force reaches zero, and the lag time of the compensating friction braking force. The transmitting unit is configured to send the air braking force corresponding to the current braking level to the BCU if it is determined that the current train speed is equal to the speed point, and send the electric braking fade signal to the TCU when the delay time reaches the lag time, so as to start controlling the reduction of the electric braking force to zero through the TCU. The control unit is configured to control the rate at which the air braking force increases based on the current braking level, a first variable slope, and a second variable slope at the initial time point when the air braking force begins to increase. The first variable slope is calculated based on a preset braking level value, the maximum air braking force corresponding to the maximum braking level, the initial time point when the air braking force begins to increase, and a first increase time point. The first increase time point is the moment when the air braking force reaches the product of the preset braking level value and the maximum air braking force.

7. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of any one of claims 1 to 5.

9. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the method of any one of claims 1 to 5.

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