Method and device for planning short-distance stop speed of urban rail transit train and medium

Abstract

The invention relates to an urban rail transit train close-range stop speed planning method and device and a medium, and the method comprises the following steps: S1, designing a plurality of close-range speed planning scenes on a reference curve level based on a train delay characteristic and an acceleration response gradual change characteristic; s2, constructing a quadratic equation speed planning module and a linear equation speed planning module according to the similarity in the operation process of various close-range speed planning scenes; and S3, giving a speed condition and a distance condition of the planning solution in each scene, and a selection mechanism when two target speed planning solutions exist. Compared with the prior art, the method has the advantages that the marking phenomenon in the close-range station stopping process can be avoided, and the operation efficiency is improved.

Description

Technical Field

[0001] The invention relates to an urban rail transit signal system, and in particular to a method, a device and a medium for planning the speed of a close-range stop of an urban rail transit train. Background Art

[0002] Urban rail transit has the advantages of large capacity, punctuality, energy saving, etc., and carries most of the passenger flow of the urban public transportation system. With the advancement of urbanization, more and more newly opened lines have adopted interconnected fully automatic operation systems to meet the increasingly high traffic density requirements. The reliability and efficiency of the train automatic driving system have a very large impact on the operating capacity of the line. The train operation density during peak hours is getting higher and higher, and the tracking interval between two cars is getting smaller and smaller, almost reaching the design upper limit of the line's operating capacity.

[0003] During the process of a train entering a station and stopping, due to interference such as the temporary closure of the signal ahead or a brief failure of the locomotive signal, there will be a phenomenon of first heavy braking and deceleration, followed by full-level traction; if the stopping point is too close at this time, the train with a large delay characteristic will easily run into the mark; this is because the reference curve calculation in the conventional stop function belongs to real-time motion planning. When the stopping point is far away, the ATO control module has enough adjustment time to allow the train to go from the interval cruising state and deceleration to the sliding mode motion state of the target stop; when the stopping point is close, if the train delay response characteristics, distance constraints, control command change rate constraints and other conditions are not considered, then the train kinematic state does not have enough time to adjust to the sliding mode motion state, and cannot follow the reference speed curve well, resulting in the train running into the mark.

[0004] Although the fully automatic operation system is equipped with forward and reverse automatic skipping functions, the train can be controlled to run slowly and at a low speed by applying small-level traction and coordinating with light braking, so as to achieve precise re-marking in the case of inaccurate stopping. However, the skipping function is suitable for precise stopping tasks within 5m of the stopping point. In close-range stopping tasks where the stopping distance exceeds 5m, the low-speed operation characteristics of the skipping function will seriously affect the operating efficiency of busy lines. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a method, device and medium for speed planning of close-range stops of urban rail transit trains.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] According to a first aspect of the present invention, a method for planning the speed of a close-range stop of an urban rail transit train is provided, the method comprising the following steps:

[0008] Step S1, designing multiple short-distance speed planning scenarios based on train delay characteristics and acceleration response gradient characteristics at the reference curve level;

[0009] Step S2, constructing a quadratic equation speed planning module and a linear equation speed planning module according to the similarities in the operation of multiple close-range speed planning scenarios;

[0010] Step S3, giving the speed conditions and distance conditions for the planning solutions in each scenario, and the selection mechanism when there are two target speed planning solutions.

[0011] As a preferred technical solution, the train delay characteristics in step S1 include traction delay, braking delay and all-common brake release delay; the acceleration response gradient characteristics include traction acceleration response, traction deceleration response, braking deceleration response, braking acceleration response and all-common brake deceleration relief characteristics.

[0012] As a preferred technical solution, the gradual change characteristics of the acceleration response in step S1 are approximately described by the acceleration change process of the constant Jerk value; the short-distance speed planning scenario in step S1 involves the differential relationship operation between the four variables of acceleration change rate, acceleration, speed and distance.

[0013] As a preferred technical solution, the quadratic equation speed planning module in step S2 includes nine time periods, namely traction delay, increasing acceleration of constant Jerk value, uniform acceleration, decreasing acceleration of constant Jerk value, uniform speed operation, increasing deceleration of constant Jerk value, uniform deceleration, and decreasing deceleration of constant Jerk value.

[0014] As a preferred technical solution, the planning solution of the quadratic equation speed planning module in step S2 is the speed of the uniform running stage, and the train initial state of the quadratic equation speed planning module includes a stationary state and a uniform running state with an initial speed.

[0015] As a preferred technical solution, the parameter configuration of the quadratic equation speed planning module in step S2 includes two types, the first type is determined by the train characteristics, including traction delay and braking delay; the second type is the project setting value, including the uniform speed segment running time, the maximum allowable acceleration value and acceleration change rate, and the minimum allowable deceleration value and deceleration change rate.

[0016] As a preferred technical solution, the quadratic equation speed planning module in step S2 includes a first speed boundary condition and a second speed boundary condition, wherein the source of the first speed boundary condition is that the time of the uniform acceleration running segment must be greater than or equal to zero, and the source of the second speed boundary condition is that the time of the uniform deceleration running segment must be greater than or equal to zero.

[0017] As a preferred technical solution, the distance boundary calculation of the quadratic equation speed planning module in step S2 depends on the speed boundary condition, and the existence condition of the planning solution of the quadratic equation speed planning module is that the parking point distance is greater than or equal to the distance boundary of the quadratic equation speed planning module.

[0018] As a preferred technical solution, the linear equation speed planning module in step S2 includes 7 time periods, namely, the train's full common brake release delay, full common brake deceleration decreasing at a constant Jerk value, uniform speed operation, increasing deceleration at a constant Jerk value, uniform deceleration, and decreasing deceleration at a constant Jerk value.

[0019] As a preferred technical solution, the planning solution of the linear equation speed planning module in step S2 is the speed of the uniform running stage, and the train initial state of the linear equation speed planning module is the moment when the train is at the beginning of releasing all common braking deceleration.

[0020] As a preferred technical solution, the parameter configuration of the linear equation speed planning module in step S2 includes two types. The first type is determined by the train characteristics, including all common braking delays and braking delays; the second type is the project setting value, including all common braking deceleration, all common braking deceleration relief change rate, uniform speed segment running time, the minimum allowable deceleration value and deceleration change rate, and the maximum allowable acceleration change rate.

[0021] As a preferred technical solution, the stop braking phase of the linear equation speed planning module in step S2 includes four time periods, namely braking delay, increasing deceleration of a constant Jerk value, uniform deceleration, and decreasing deceleration of a constant Jerk value.

[0022] As a preferred technical solution, the distance boundary of the first-order equation speed planning module in step S2 includes three parts of running distance, namely, the running distance of the full common braking release delay period, the running distance of the full common braking deceleration relief change period, and the running distance of the stop braking period;

[0023] The existence condition of the planning solution of the linear equation speed planning module is that the parking point distance is greater than or equal to the distance boundary of the linear equation speed planning module.

[0024] As a preferred technical solution, each scenario in step S3 includes a stationary state planning scenario and a deceleration state planning scenario, wherein the initial state of the train in the deceleration state planning scenario is the moment when the train is at the beginning of the release of full common braking deceleration, and the deceleration state planning scenario includes a first sub-scenario, a second sub-scenario and a third sub-scenario;

[0025] The first sub-scenario is the process of the quadratic equation speed planning module in which the train speed drops to zero during the full brake release delay period and then enters a stationary state;

[0026] The second sub-scenario is the process of the quadratic equation speed planning module when the train speed drops to zero during the full service braking deceleration relief period and then enters the stationary state;

[0027] The third sub-scenario is that the speed of the train does not drop to zero after all normal braking is released. At this time, there are two possible solutions, namely, the quadratic equation planning speed solution and the linear equation planning speed solution.

[0028] As a preferred technical solution, the initial speed value of the quadratic equation speed planning module in the first sub-scenario is 0, and the initial distance value is the parking point distance minus the actual running distance within the full common brake release delay period;

[0029] The initial speed value of the quadratic equation speed planning module in the second sub-scenario is 0, and the initial distance value is the parking point distance minus the running distance in two time periods, which are the running distance in the full common brake release delay period and the actual running distance in the full common brake deceleration relief period;

[0030] The initial speed value of the quadratic equation speed planning module in the third sub-scenario is the estimated speed when the full common braking deceleration is relieved to 0, and the initial distance value is the parking point distance minus the running distance of two time periods, namely the running distance of the full common braking release delay period and the running distance of the full common braking deceleration relief time period.

[0031] As a preferred technical solution, the initial speed value of the linear equation speed planning module in the third sub-scenario is the train speed at the moment when all common brakes begin to release, and the initial distance value is the distance to the parking point.

[0032] According to a second aspect of the present invention, there is provided an electronic device, comprising a memory and a processor, wherein a computer program is stored in the memory, and the method described above is implemented when the processor executes the program.

[0033] According to a third aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the program implements the method described above when executed by a processor.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] 1) At the reference curve level, in addition to considering the delay characteristics of the train, the present invention also uses the acceleration change process of the constant Jerk value to approximately describe the first-order response process of the train acceleration. Therefore, the planned target speed curve is suitable for the train traction braking response characteristics during close-range stops.

[0036] 2) Compared with the conventional stop function, the present invention can avoid the phenomenon of collision during the close-distance stop process.

[0037] 3) Compared with the jump function, the present invention can stop at the platform accurately while ensuring operational efficiency

[0038] 4) The present invention fills the gap between the conventional stop function and the jump function. The three functions complement each other and just cover the stop needs within the entire distance range. Their rational use not only ensures accurate stopping targets but also improves operational efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of various variables in the process of short-distance speed planning of urban rail transit trains of the present invention;

[0040] Figure 2 This is a schematic diagram of the classification of speed planning scenarios for close-range stops of urban rail transit trains according to the present invention;

[0041] Figure 3 This is a functional flow chart of the speed planning of a close-range stop of an urban rail transit train according to the present invention;

[0042] Figure 4 It is a schematic diagram of the quadratic equation speed planning of a close-range stop of an urban rail transit train according to the present invention;

[0043] Figure 5 It is a schematic diagram of first-order equation speed planning for close-range stops of urban rail transit trains according to the present invention;

[0044] Figure 6 The urban rail transit train T of the present invention ird Schematic diagram of speed planning with zero speed reduction within time;

[0045] Figure 7 The urban rail transit train T of the present invention irj Schematic diagram of speed planning with zero speed reduction within time;

[0046] Figure 8 It is a schematic diagram of two speed planning solutions for a close-range stop of an urban rail transit train according to the present invention. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0048] In order to solve the problem of hitting the mark in the task of close-distance stop of urban rail transit trains, the present invention provides a speed planning method for this task. At the reference curve level, a variety of close-distance stop speed planning scenarios are designed by comprehensively considering the train delay and acceleration response characteristics. According to the similarities in the operation process of various scenarios, two basic modules are reconstructed, namely the quadratic equation speed planning module and the linear equation speed planning module. The speed conditions and distance conditions of the planning solutions in each scenario are discussed, as well as the selection mechanism when there are two planning solutions.

[0049] The present invention is achieved through the following technical solutions, which are as follows:

[0050] Step 1: Describe the short-distance speed planning process based on the train delay characteristics and acceleration response gradient characteristics;

[0051] Step 2: Establish the basic module of quadratic equation speed planning and give the existence conditions of the planning solution;

[0052] Step 3: Establish the basic module of linear equation speed planning and give the existence conditions of the planning solution;

[0053] Step 4: The initial conditions for the speed planning solutions of the quadratic equation and the linear equation in the composite scenario are given;

[0054] Step 5: A selection mechanism is given when there are two target speed planning solutions in a composite scenario.

[0055] The train delay characteristics in step 1 include traction delay, braking delay and full common brake release delay.

[0056] The train acceleration response gradient characteristics in step 1 include traction acceleration response, traction deceleration response, braking deceleration response, braking acceleration response and all common braking deceleration mitigation characteristics.

[0057] The gradual change characteristic of the acceleration response in step 1 is approximately described by the acceleration change process of the constant Jerk value.

[0058] The short-distance speed planning process in step 1 involves differential relationship operations among four variables: acceleration rate (ie, Jerk), acceleration, speed, and distance.

[0059] The quadratic equation speed planning process in step 2 includes 9 time periods, namely, traction delay, increasing acceleration of constant Jerk value, uniform acceleration, decreasing acceleration of constant Jerk value, uniform speed operation (including braking delay), increasing deceleration of constant Jerk value, uniform deceleration, and decreasing deceleration of constant Jerk value.

[0060] The speed planning solution of the quadratic equation in step 2 refers to the speed in the uniform speed operation stage.

[0061] The initial state of the train in the quadratic equation speed planning in step 2 includes a stationary state and a uniform speed running state with an initial speed.

[0062] There are two types of parameter configurations for the quadratic equation speed planning in step 2. The first type is determined by the train characteristics, including traction delay and braking delay; the second type is the project setting value, including the uniform speed segment running time, the maximum allowable acceleration value and acceleration change rate, and the minimum allowable deceleration value and deceleration change rate.

[0063] The source of the first speed boundary condition of the quadratic equation speed planning in step 2 is that the time of the uniform acceleration running section must be greater than or equal to zero.

[0064] The source of the second speed boundary condition of the quadratic equation speed planning in step 2 is that the time of the uniform deceleration operation segment must be greater than or equal to zero.

[0065] The distance boundary calculation of the quadratic equation velocity planning in step 2 described above depends on the velocity boundary condition.

[0066] The existence condition of the solution of the quadratic equation speed planning in step 2 is that the parking point distance is greater than or equal to the distance boundary of the quadratic equation speed planning.

[0067] The first-order equation speed planning process in step 3 includes 7 time periods, namely, the train's full common brake release delay, full common brake deceleration decreasing at a constant Jerk value, uniform speed operation (including braking delay), constant Jerk value deceleration increasing, uniform deceleration, and constant Jerk value deceleration decreasing.

[0068] The speed planning solution of the first-order equation in step 3 refers to the speed in the uniform speed operation stage.

[0069] The initial state of the train in the first-order equation speed planning in step 3 is the moment when the train is at the beginning of releasing the full common braking deceleration.

[0070] There are two types of parameter configurations for the linear equation speed planning in step 3. The first type is determined by the train characteristics, including all common braking delays and braking delays; the second type is the project setting value, including all common braking deceleration, all common braking deceleration relief change rate, uniform speed segment running time, the minimum allowable deceleration value and deceleration change rate, and the maximum allowable acceleration change rate.

[0071] The stop braking phase in the first-order equation speed planning process in step 3 is composed of four time periods, namely, braking delay, increasing deceleration of constant Jerk value, uniform deceleration, and decreasing deceleration of constant Jerk value.

[0072] The distance boundary of the first-order equation speed planning in step 3 is composed of three running distances, namely, the running distance of the full common braking release delay period, the running distance of the full common braking deceleration relief change period, and the running distance of the stop braking period.

[0073] The existence condition of the solution of the speed planning of the linear equation in step 3 is that the distance of the parking point is greater than or equal to the distance boundary of the speed planning of the linear equation.

[0074] The initial state of the train in the composite scenario in step 4 is the moment when the train is at the beginning of releasing the full common braking deceleration.

[0075] The first sub-scenario under the composite scenario in step 4 is a quadratic equation speed planning process in which the train speed drops to zero during the full brake release delay period and then enters a stationary state.

[0076] In the first sub-scenario under the composite scenario in step 4, the initial speed value of the quadratic equation speed planning is 0, and the initial distance value is the parking point distance minus the actual running distance within the full common brake release delay period.

[0077] The second sub-scenario under the composite scenario in step 4 is a quadratic equation speed planning process in which the train speed drops to zero during the full common braking deceleration relief time period and then enters a stationary state.

[0078] The initial speed value of the quadratic equation speed planning in the second sub-scenario under the composite scenario in step 4 is the estimated speed when the full common braking deceleration is relieved to 0, and the initial distance value is the parking point distance minus the running distance of two time periods, which are the running distance of the full common braking release delay period and the actual running distance in the full common braking deceleration relief time period.

[0079] The third sub-scenario under the composite scenario in step 4 is that the speed of the train does not drop to zero after all the normal braking is released. At this time, there are two possible solutions, namely, the quadratic equation planning speed solution and the linear equation planning speed solution.

[0080] The initial speed value of the quadratic equation speed planning in the third sub-scenario under the composite scenario in step 4 is 0, and the initial distance value is the parking point distance minus the running distance of two time periods, which are the running distance of the full common brake release delay period and the running distance of the full common brake deceleration relief time period.

[0081] The initial speed value of the first-order equation speed planning in the third sub-scenario under the composite scenario in step 4 is the train speed at the moment when all common brakes begin to release, and the initial distance value is the distance to the stopping point.

[0082] The specific implementation process of the present invention is as follows:

[0083] 1. Speed ​​planning process for short-distance stops

[0084] Since the train is a large inertia time-delay system, the train's delay characteristics and acceleration response characteristics must be considered during the speed planning of the train's close-range stops. The first-order time-delay system is usually used to describe the traction and braking model of urban rail transit trains, as shown in formula (1):

[0085]

[0086] Among them, K is the steady-state gain coefficient, which represents the mapping relationship between the output level of the signal system and the train response acceleration in steady state, and T and τ They are the system time constant and pure delay respectively, representing the transient characteristics of the system.

[0087] In order to characterize the transient characteristics of acceleration described in formula (1), in the process of speed planning for close-range train stops, in addition to considering the delay characteristics of the train, it is also necessary to consider the gradual characteristics of the acceleration response. Here, the acceleration change process of the constant Jerk value is used to approximate the first-order response process of acceleration.

[0088] The speed planning process involves the differential relationship operation between four variables, namely, the acceleration rate (i.e., Jerk), acceleration, speed, and distance. These variables describe the train response process, as shown in formula (2):

[0089]

[0090] Among them, t represents the time variable, t0 represents the initial time of planning, a(t) represents the acceleration variable, v(t) represents the speed variable, s(t) represents the distance variable, and J represents the acceleration change rate, which is a constant in the time period [t0, t].

[0091] Figure 1 The speed planning process of the train departure in a stationary state and the graphical curves of the relevant variables in each stage are shown. The train response characteristics after departure in a stationary state can be approximately described by 9 stages, namely traction delay, traction acceleration response, uniform acceleration, traction deceleration response, uniform speed (including braking delay), braking deceleration response, uniform deceleration, and braking acceleration response. The traction delay and braking delay stages take into account the traction and braking delay characteristics of the train; in the four stages of traction acceleration response, traction deceleration response, braking deceleration response, and braking acceleration response, the Jerk value is a project configuration parameter combined with the train response characteristics; in addition, the uniform speed section running time, the acceleration values ​​of the uniform acceleration and uniform deceleration stages are also project configuration parameters. Finally, the cumulative planning distance of each stage needs to meet the condition of being equal to the distance of the train stop point.

[0092] 2. Short-distance stop speed planning scenario

[0093] Consider the short-distance stop speed planning under two conditions: the first is the target speed planning when the train is stationary, and the second is the target speed planning when the train is decelerating and braking. The second type of target speed planning can be further subdivided into multiple sub-scenarios. Figure 2 Three typical scenarios in the speed planning scenario of close-distance stops are shown. Typical scenario 1 is that the train starts from a stationary state and goes through three operating stages: traction, uniform speed, and braking. Typical scenario 2 is that the train goes through three operating stages: traction, uniform speed, and braking after the deceleration and braking process. Typical scenario 3 is that the train goes through two operating stages: uniform speed and braking after the deceleration and braking process. Based on the similarities in the operation process of various scenarios, two basic modules can be reconstructed, namely the quadratic equation speed planning module and the linear equation speed planning module.

[0094] The function flow of train close-distance stop speed planning is as follows Figure 3 As shown, first determine whether the train is within the preset threshold area range from the parking point. If the condition is not met, speed planning is not performed. The reasons are as follows: one case is that the train is far enough from the parking point. At this time, similar to the conventional stop process, the train has enough time to enter the sliding mode motion state during the braking process to ensure the stop accuracy. Another case is that the train is too close to the parking point. At this time, the low-speed jump function is required to achieve accurate parking. If the parking point distance condition is met, the target speed planning process under two states is entered. If the train is in a stationary state, the quadratic equation speed planning module with an initial speed of zero is used for target speed planning. If the train is in a braking and deceleration state due to interference from the line ahead, at the moment when the interference disappears, it is necessary to estimate the train speed at the end of the brake release process. If the estimated speed is zero, the quadratic equation speed planning module with an initial speed of zero can be used. If the estimated speed is not zero, there may be target speed planning processes under typical scenarios 2 and 3 at this time. It is necessary to calculate the quadratic equation planning speed for traction after brake release and the linear equation planning speed for uniform speed after brake release. If two planning solutions exist at the same time, in order to ensure operational efficiency, the planning solution with the largest target speed is selected.

[0095] 3. Speed ​​planning solution of quadratic equation and its existence conditions

[0096] Figure 4 The target speed planning process for train departure under stationary condition is shown. Figure 2 In the typical scenario 1, there are 9 time periods in total, and the planned speed of the uniform speed period can be obtained by the quadratic equation. mdThe time period represents the train traction delay. The T1 time period represents the traction acceleration change process of the constant Jerk value. The T2 time period represents the uniform acceleration process. The T3 time period represents the traction deceleration change process of the constant Jerk value. The T4 time period represents the uniform speed operation process. bd The time period represents the train braking delay, the T5 time period represents the braking deceleration change process of the constant Jerk value, the T6 time period represents the uniform deceleration process, and the T7 time period represents the braking acceleration change process of the constant Jerk value. md and T bd It is related to the delay characteristics of the train and is a determined constant value. T4 is the project setting value and is also a determined constant value. The planned speed V in the uniform speed stage is the variable to be solved.

[0097] The acceleration change process time of the four constant Jerk values ​​is shown in formula (3).

[0098]

[0099] Among them A max and A min They represent the maximum and minimum acceleration values ​​allowed in the target speed planning process, J max and J min They respectively represent the maximum and minimum values ​​of the allowed acceleration change rate.

[0100] Although the initial speed of the train is zero in this scenario, without loss of generality, the initial speed is represented by the variable v0. The stopping point distance is represented by the symbol S. Applying the condition that the sum of the running distances in each time period is equal to the stopping point distance, the quadratic equation calculation expression of the planned speed V can be obtained, as shown in formula (4):

[0101] AV 2 +BV+C=0 (4)

[0102] The expression of the quadratic term coefficient A is as follows:

[0103] A=1 / (2A max )-1 / (2A min ),

[0104] The expression of the linear coefficient B is as follows:

[0105] B=T4+T bd +(T3+T5) / 2,

[0106] The expression of the constant term coefficient C is as follows,

[0107]

[0108] According to the requirement that the time period T2 of uniform acceleration operation is not less than zero, the first boundary condition of the planned speed is obtained, as shown in formula (5):

[0109] V lim_1 =v0+A max (T1+T3) / 2 (5)

[0110] Similarly, the uniform deceleration time period T6 should not be less than zero, and the second boundary condition of the planned speed is obtained, as shown in formula (6):

[0111] V lim_2 =-A min (T5+T7) / 2 (6)

[0112] Therefore, by combining formula (5) and formula (6), the final planning speed boundary condition is obtained, as shown in formula (7):

[0113] V lim =max(V lim_1 , V lim_2 ) (7)

[0114] According to the boundary conditions of the planned speed V lim , we can get the distance boundary condition expression s lim_two_order As shown in formula (8), the parking point distance S must be greater than or equal to s lim_two_order , otherwise there is no solution to the quadratic equation for speed planning.

[0115] s lim_two_order =s md +s1+s2+s3+s4+s bd +s5+s6+s7 (8)

[0116] The expressions are as follows:

[0117] s md =v0T md ,

[0118]

[0119] s4=V lim T4,

[0120] s bd =V lim T bd ,

[0121]

[0122] 4. Speed ​​planning solution of linear equation and its existence conditions

[0123] Figure 5The first-order equation target speed planning process under the train deceleration state is shown, corresponding to Figure 2 Typical scenario 3 in the above example has a total of 7 time periods. ird The time period indicates the delay in releasing the train's full service brakes. At the beginning of this time period, the train receives information such as the opening of the route ahead and begins to release the previously applied full service brakes. irj The time period represents the full-time braking deceleration relief process of the constant Jerk value, the T4 time period represents the uniform speed running process, and the T bd The time period represents the train braking delay. The T5 time period represents the braking deceleration change process of the constant Jerk value. The T6 time period represents the uniform deceleration process. The T7 time period represents the braking acceleration change process of the constant Jerk value.

[0124] Using T ird and T bd The difference between full-time braking delay and braking delay is expressed as follows. These two values ​​are related to the train delay characteristics and are constant values. ird and T irj During these two time periods, the train speed drops to the running speed of the T4 uniform speed section, which is represented by the symbol V. This value can be determined. In the process of speed planning by the linear equation, T4 is the variable to be solved.

[0125] The acceleration change process time of the three constant Jerk values ​​is shown in formula (9):

[0126]

[0127] Among them A immo Indicates the full normal braking deceleration, J immo Indicates the rate of change of the full-service braking deceleration, A min Indicates the minimum allowable braking deceleration, J min and J max Indicates the minimum and maximum allowable braking deceleration rate of change.

[0128] After T ird and T irj The expression of the train's uniform speed V after time, that is, the speed solution of the first-order equation, is shown in formula (10):

[0129] V=v0+A immo T ird +A immo T irj / 2 (10)

[0130] According to the condition that the sum of the running distances in each time period is equal to the parking point distance, the linear equation calculation expression of the uniform speed section running time T4 can be obtained, as shown in formula (11):

[0131] VT4+s lim_one_order =S (11)

[0132] Where T4 is the variable to be solved, V is the uniform speed obtained by formula (10), S is the distance to the parking point, s lim_one_order is the distance limit of the first-order equation planning speed, as shown in formula (12),

[0133] s lim_one_order =s ird +s irj +s one_order (12)

[0134] The expressions are as follows:

[0135]

[0136] If the parking point distance S is greater than or equal to s lim_one_order , then the uniform speed segment time T4 obtained by formula (11) is greater than or equal to zero, indicating that the speed planning solution of the linear equation is valid. On the contrary, if the distance boundary condition is not met, there is no speed planning solution of the linear equation.

[0137] 5. Speed ​​planning solution and selection mechanism in complex scenarios

[0138] Here is the target speed planning process of the first-order equation or the second-order equation for the initial speed of the train in the composite scenario. Figure 2 Typical scenario 2 in the above is just an example of a composite scenario. ird and T irj The train speed reduction in these two time periods has the following three sub-scenario: ird The train speed has dropped to zero during the time period. The second sub-scenario is in T irj The train speed drops to zero during the time period. The third sub-scenario is when the train passes through T ird and T irj After these two time periods, the train speed did not drop to zero.

[0139] The first sub-scenario is T ird The train speed drops to zero during the time period, e.g. Figure 6 As shown, during the train brake release delay T ird During the time period, the train's full braking deceleration is A immo According to formula (13), the actual running distance of the train when the speed drops to zero is obtained.

[0140]

[0141] Among them, t ird =-v0 / Aimmo .

[0142] The target speed planning process is the same as the quadratic equation speed planning scenario in the static state, with an initial speed of 0 and a distance value of SS. ird .

[0143] The second sub-scenario is T irj The train speed drops to zero during the time period, e.g. Figure 7 As shown, that is, after the full normal brake release delay T ird After that, the train speed did not drop to zero until T irj The train speed drops to zero during this time period. irj The time taken for the train speed to drop to zero within the time period can be obtained by equation (14):

[0144] J immo t 2 / 2+A immo t+v0+A immo T ird =0 (14)

[0145] Eligible solutions irj The expression is shown in formula (15),

[0146]

[0147] The discriminant

[0148] In t irj The actual running distance within the time period is shown in formula (16):

[0149]

[0150] The target speed planning process is the same as the quadratic equation speed planning scenario in the static state, with an initial speed of 0 and a distance value of Ss. ird -S irj .

[0151] The third sub-scenario is that the train speed does not drop to zero after all the normal braking is released, that is, after passing T ird and T irj After these two time periods, the train speed has not dropped to zero. At this time, if the distance conditions and speed conditions are suitable, the result of the short-distance stop speed planning is that there are both quadratic equation speed planning solutions and linear equation speed planning solutions. The initial speed value v0 of the linear equation planning process and the distance value S. The initial speed value V of the quadratic equation planning process immo is the estimated speed when the full common braking deceleration is relieved to 0, as shown in formula (17),

[0152] V immo =v0+A immo T ird +A immo T irj / 2 (17)

[0153] The distance value is Ss ird -s irj .

[0154] like Figure 8 As shown in the figure, the left figure is the planned speed solution of the linear equation, with a planned speed of 3.6 kph. The last section of the distance runs at an approximate planned speed, and the entire section takes 146.6 seconds. The right figure is the planned speed solution of the quadratic equation. The planned speed of the train is 7.5 kph. There are traction acceleration, constant speed and braking processes. Due to the high planned speed, the entire section takes only 140.6 seconds, which saves 6 seconds of running time compared to the left figure. From the perspective of actual operation, choosing the largest of the two planned speed solutions can save running time and improve operational efficiency. Therefore, if both planning solutions exist, choose the largest planned speed.

[0155] The above is an introduction to the method embodiment. The following is a further explanation of the scheme of the present invention through electronic equipment and storage medium embodiments.

[0156] The embodiment of the present invention also provides an electronic device including a central processing unit (CPU), which can perform various appropriate actions and processes according to computer program instructions stored in a read-only memory (ROM) or computer program instructions loaded from a storage unit into a random access memory (RAM). In the RAM, various programs and data required for device operation can also be stored. The CPU, ROM, and RAM are connected to each other via a bus. An input / output (I / O) interface is also connected to the bus.

[0157] Multiple components in the device are connected to the I / O interface, including: input units, such as keyboards, mice, etc.; output units, such as various types of displays, speakers, etc.; storage units, such as disks, optical disks, etc.; and communication units, such as network cards, modems, wireless communication transceivers, etc. The communication unit allows the device to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunication networks.

[0158] The processing unit performs the various methods and processes described above, such as the method of the present invention. For example, in some embodiments, the method of the present invention can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program can be loaded and / or installed on the device via a ROM and / or a communication unit. When the computer program is loaded into RAM and executed by the CPU, one or more steps of the method of the present invention described above can be performed. Alternatively, in other embodiments, the CPU can be configured to perform the method of the present invention by any other appropriate means (e.g., by means of firmware).

[0159] The functions described above herein may be performed at least in part by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that may be used include: field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), complex programmable logic devices (CPLDs), and the like.

[0160] The program code for implementing the method of the present invention can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code can be executed entirely on the machine, partially on the machine, partially on the machine as a stand-alone software package and partially on a remote machine, or entirely on a remote machine or server.

[0161] In the context of the present invention, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination of the foregoing. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0162] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for planning the speed of a close-range stop of an urban rail transit train, characterized in that: The method comprises the following steps: Step S1, designing multiple short-distance speed planning scenarios based on train delay characteristics and acceleration response gradient characteristics at the reference curve level; Step S2, constructing a quadratic equation speed planning module and a linear equation speed planning module according to the similarities in the operation of multiple close-range speed planning scenarios; Step S3, giving the speed conditions and distance conditions for the planning solutions in each scenario, and the selection mechanism when there are two target speed planning solutions.

2. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The train delay characteristics in step S1 include traction delay, braking delay and all-common brake release delay; the acceleration response gradual change characteristics include traction acceleration response, traction deceleration response, braking deceleration response, braking acceleration response and all-common brake deceleration relief characteristics.

3. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The gradual change characteristic of the acceleration response in step S1 is approximately described by the acceleration change process of the constant Jerk value; the short-distance speed planning scenario in step S1 involves the differential relationship operation between the four variables of acceleration change rate, acceleration, speed and distance.

4. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The quadratic equation speed planning module in step S2 includes nine time periods, namely, traction delay, increasing acceleration of constant Jerk value, uniform acceleration, decreasing acceleration of constant Jerk value, uniform speed operation, increasing deceleration of constant Jerk value, uniform deceleration, and decreasing deceleration of constant Jerk value.

5. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The planning solution of the quadratic equation speed planning module in step S2 is the speed of the uniform speed operation stage, and the train initial state of the quadratic equation speed planning module includes a stationary state and a uniform speed operation state with an initial speed.

6. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The parameter configuration of the quadratic equation speed planning module in step S2 includes two types, the first type is determined by the train characteristics, including traction delay and braking delay; the second type is the project setting value, including the uniform speed segment running time, the maximum allowable acceleration value and acceleration change rate, and the minimum allowable deceleration value and deceleration change rate.

7. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The quadratic equation speed planning module in step S2 includes a first speed boundary condition and a second speed boundary condition, wherein the source of the first speed boundary condition is that the time of the uniform acceleration running segment must be greater than or equal to zero, and the source of the second speed boundary condition is that the time of the uniform deceleration running segment must be greater than or equal to zero.

8. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The distance boundary calculation of the quadratic equation speed planning module in step S2 depends on the speed boundary condition, and the existence condition of the planning solution of the quadratic equation speed planning module is that the parking point distance is greater than or equal to the distance boundary of the quadratic equation speed planning module.

9. According to claim 1, a method for planning the speed of a close-range stop of an urban rail transit train is characterized in that: The first-order equation speed planning module in step S2 includes 7 time periods, namely, the train's full-common brake release delay, full-common brake deceleration decreasing at a constant Jerk value, uniform speed operation, constant Jerk value deceleration increasing, uniform deceleration, and constant Jerk value deceleration decreasing.

10. The method for planning the speed of a close-range stop of an urban rail transit train according to claim 1, characterized in that: The planning solution of the linear equation speed planning module in step S2 is the speed in the uniform running stage, and the train initial state of the linear equation speed planning module is the moment when the train is at the beginning of releasing the full common braking deceleration.

11. The method for planning the speed of a close-range stop of an urban rail transit train according to claim 1, characterized in that: The parameter configuration of the linear equation speed planning module in step S2 includes two types. The first type is determined by the train characteristics, including all common braking delays and braking delays; the second type is the project setting value, including all common braking deceleration, all common braking deceleration relief change rate, uniform speed segment running time, the minimum allowable deceleration value and deceleration change rate, and the maximum allowable acceleration change rate.

12. The method for planning the speed of a close-range stop of an urban rail transit train according to claim 1, characterized in that: The stop braking phase of the first-order equation speed planning module in step S2 includes four time periods, namely, braking delay, increasing deceleration of a constant Jerk value, uniform deceleration, and decreasing deceleration of a constant Jerk value.

13. The method for planning the speed of a close-range stop of an urban rail transit train according to claim 1, characterized in that: The distance boundary of the first-order equation speed planning module in step S2 includes three parts of running distance, namely, the running distance of the full common braking release delay period, the running distance of the full common braking deceleration relief change period, and the running distance of the stop braking period; The existence condition of the planning solution of the linear equation speed planning module is that the parking point distance is greater than or equal to the distance boundary of the linear equation speed planning module.

14. The method for planning the speed of a close-range stop of an urban rail transit train according to claim 1, characterized in that: Each scenario in step S3 includes a stationary state planning scenario and a deceleration state planning scenario, wherein the initial state of the train in the deceleration state planning scenario is the moment when the train is at the start of full common braking deceleration release, and the deceleration state planning scenario includes a first sub-scenario, a second sub-scenario and a third sub-scenario; The first sub-scenario is the process of the quadratic equation speed planning module in which the train speed drops to zero during the full brake release delay period and then enters a stationary state; The second sub-scenario is the process of the quadratic equation speed planning module when the train speed drops to zero during the full service braking deceleration relief period and then enters the stationary state; The third sub-scenario is that the speed of the train does not drop to zero after all normal braking is released. At this time, there are two possible solutions, namely, the quadratic equation planning speed solution and the linear equation planning speed solution.

15. A method for planning the speed of a close-range stop of an urban rail transit train according to claim 14, characterized in that: The initial speed value of the quadratic equation speed planning module in the first sub-scenario is 0, and the initial distance value is the parking point distance minus the actual running distance within the full service brake release delay period; The initial speed value of the quadratic equation speed planning module in the second sub-scenario is 0, and the initial distance value is the parking point distance minus the running distance in two time periods, which are the running distance in the full common brake release delay period and the actual running distance in the full common brake deceleration relief period; The initial speed value of the quadratic equation speed planning module in the third sub-scenario is the estimated speed when the full common braking deceleration is relieved to 0, and the initial distance value is the parking point distance minus the running distance of two time periods, namely the running distance of the full common braking release delay period and the running distance of the full common braking deceleration relief time period.

16. A method for planning the speed of a close-range stop of an urban rail transit train according to claim 14, characterized in that: The initial speed value of the first-order equation speed planning module in the third sub-scenario is the train speed at the moment when all common brakes begin to release, and the initial distance value is the distance to the parking point.

17. An electronic device comprising a memory and a processor, wherein a computer program is stored in the memory, wherein: When the processor executes the program, the method according to any one of claims 1 to 16 is implemented.

18. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 16 is implemented.

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