A coordinated path chain green wave bandwidth multi-round optimization method

Abstract

The application discloses a kind of coordinated path chain green wave bandwidth multi-wheel optimization method, this method includes: determining the coordinated phase and its green light start-stop time point of each coordinated path chain through intersection;According to the number of coordinated path included in each coordinated path chain, determine the maximum number of green wave bandwidth optimization rounds of each coordinated path chain and each round coordinated path set, determine the maximum number of green wave bandwidth optimization rounds of control area;For each round coordinated path set, calculate the upper shift allowance, the lower shift allowance of each intersection phase difference in each round, determine the intersection phase difference adjustment object and adjustment amount;Output the final result of the phase difference adjustment amount of each intersection.The application comprehensively analyzes the upper shift allowance and the lower shift allowance of the phase difference of each signal intersection, and on the basis of ensuring that the whole green wave bandwidth does not change, a multi-round optimization method for green wave bandwidth of each level coordinated path chain is proposed, which can simultaneously optimize multiple coordinated path chains in the control area.

Description

Technical Field

[0001] This invention belongs to the technical field of traffic signal control, specifically relating to a multi-round optimization method for green wave bandwidth of coordinated path chains. Background Technology

[0002] Green wave coordinated control enables vehicles to pass through multiple signalized intersections continuously without stopping, reducing delays and stops caused by waiting at red lights, thus improving traffic flow. However, current design methods for green wave coordinated control often prioritize maximizing the green wave bandwidth of the entire arterial road or the sum of the green wave bandwidths of individual road segments, failing to consider the variable length of the coordinated path chain to achieve comprehensive optimization of the green wave bandwidth at each level. Further research is needed to explore how to rationally adjust the phase difference at each intersection to optimize the green wave bandwidth at each level of the coordinated path chain without altering the overall green wave bandwidth. Summary of the Invention

[0003] The main objective of this invention is to overcome the shortcomings and deficiencies of existing technologies and provide a multi-round optimization method for the green wave bandwidth of coordinated path chains. To achieve the above objective, this invention adopts the following technical solution:

[0004] One aspect of the present invention provides a multi-round optimization method for coordinating path chain green wave bandwidth, comprising the following steps:

[0005] Determine the coordination phase and the start and end times of the green lights at the intersections traversed by each coordination path chain;

[0006] Based on the number of coordination paths contained in each coordination path chain, determine the maximum number of rounds for green wave bandwidth optimization for each coordination path chain and the coordination path set for each round, and determine the maximum number of rounds for green wave bandwidth optimization in the control area.

[0007] For each round of coordinated path sets, calculate the allowable upward and downward shift of the phase difference at each intersection in each round, and determine the objects and amounts of phase difference adjustment at intersections;

[0008] Output the final result of the phase difference adjustment for each intersection.

[0009] As a preferred technical solution, determining the coordination phase and the start and end times of the green lights at the intersections traversed by each coordination path chain specifically involves:

[0010] Based on the initial green wave coordination design scheme, determine each coordination path chain L. i At intersection I j Coordination phase k (i,j) And the corresponding initial start time T of the green light GS(i,j) and the initial green light end time point T GE(i,j) .

[0011] As a preferred technical solution, each coordination path chain L i Green wave bandwidth optimization maximum number of rounds r maxi For N i -1, N i To coordinate path chain L i The number of intersections included;

[0012] The coordination path set for each round is the optimization object for each coordination path chain in that round for green wave bandwidth optimization. Specifically, it defines the coordination path chain L. i The p-th coordination path is a coordination path chain. The first coordination path in the process, for a given coordination path chain L i , with r coordinated path chains L i In continuous N i -r coordination path chains As the optimization target for the r-th round of green wave bandwidth optimization;

[0013] The maximum number of rounds for optimizing the green wave bandwidth in the control area is R. max =max{r maxi}

[0014] As a preferred technical solution, the step of calculating the allowable upward and downward shift of the phase difference at each intersection in each round for each round of coordinated path sets, and determining the adjustment objects and adjustment amounts of the intersection phase difference, specifically involves:

[0015] Perform the t-th optimization in the r-th round:

[0016] S301. Determine the start and end times of the green light:

[0017] Determine each coordination path chain L i At intersection I j Coordination phase k (i,j) Green light start time and the end time of the green light The calculation formula is as follows:

[0018]

[0019]

[0020] In the formula, T GS(i,j) T GE(i,j) Each coordination path chain L i At intersection I j Coordination phase k (i,j) The initial start time and the initial end time of the green light; Intersection Ij The phase difference adjustment amount, where during the first optimization in the first round.

[0021] S302. Determine the start and end times of the green wave band:

[0022] Determine each coordination path chain At intersection I j Green wave start time and the end time of the green wave

[0023] S303. Determine the allowable upward and downward shift of the phase difference:

[0024] Determine each coordination path chain At intersection I j Phase difference shift tolerance and downward allowance The calculation formula is as follows:

[0025]

[0026]

[0027] Define the coordination path chain China satisfies and The intersections form coordinated path chains. Phase difference shift tolerance bottleneck set and the bottleneck set of phase difference downshift tolerance satisfy and The intersections form coordinated path chains. Phase difference shift tolerance non-bottleneck set Phase difference downshift tolerance non-bottleneck set

[0028] Determine the coordinated path set at intersection I j Phase difference shift tolerance and downward allowance The calculation formula is as follows:

[0029]

[0030]

[0031] Definition satisfies and The intersections respectively constitute the coordinated path set, phase difference upward shift tolerance, and bottleneck set. and the bottleneck set of phase difference downshift tolerance

[0032] S304. Divide the coordinated path chain set according to whether the green wave bandwidth has reached the limit value:

[0033] Based on whether the green wave bandwidth of each coordinated path chain has reached its limit, define the set of coordinated path chains whose green wave bandwidth has reached its limit. Set of coordinated path chains where green wave bandwidth has not reached its limit

[0034] S305, Determine the termination of green wave bandwidth optimization and determine the phase difference adjustment object and adjustment amount.

[0035] As a preferred technical solution, in step S304, the condition for the green wave bandwidth to reach the limit value is:

[0036] For coordinating path chains intersection like Intersection Simultaneously, within the bottleneck set of phase difference and downward displacement tolerance of the coordinated path set, and at the intersection In the coordination path chain Within the bottleneck sets of phase difference upward shift tolerance and phase difference downward shift tolerance, the coordinated path chain is as follows. The green wave bandwidth reaches its limit; especially if the intersection... Coordinate path chains at the same intersection The green wave bandwidth is the intersection bandwidth. Coordinate phase time.

[0037] As a preferred technical solution, step S305, which involves determining the termination of green wave bandwidth optimization and identifying the phase difference adjustment target and adjustment amount, specifically includes:

[0038] Based on the allowable up and down shifts in phase difference and the set of coordinated path chains, the following classifications are included:

[0039] Case 1: If That is, all coordinated path chains in the r-th round and t-th green wave bandwidth optimization. The green wave bandwidth has reached its limit. At this point, it is determined whether the green wave bandwidth optimization termination condition is met. If it is met, the green wave bandwidth optimization ends. At this time, intersection I j Phase difference adjustment amount Jump to the step of outputting the final result of the phase difference adjustment for each intersection; if the condition is not met, do not adjust intersection I. j Phase difference adjustment is performed at intersection I. j The phase difference adjustment amount is: Return to S301 to continue the first green wave bandwidth optimization in the (r+1)th round;

[0040] Scenario 2: If That is, a coordinated path chain exists in the r-th round and t-th green wave bandwidth optimization. The green wave bandwidth has not yet reached its limit. At this point, calculate intersection I. j The specific steps for adjusting the phase difference are as follows:

[0041] Determine the coordinated path chains for each green wave whose bandwidth has not yet reached its limit. Minimum non-zero phase difference upshift tolerance and downward allowance The calculation formula is as follows:

[0042]

[0043]

[0044] Determine the minimum non-zero phase difference upshift tolerance for the coordinated path set. and downward allowance The calculation formula is as follows:

[0045]

[0046]

[0047] Define the minimum non-zero phase difference upshift tolerance of the coordinated path set at this time. To coordinate the path chain At the intersection Phase difference shift tolerance Minimum non-zero phase difference downshift tolerance for coordinated path sets To coordinate the path chain At the intersection Phase difference downshift tolerance

[0048] Define the common signal period of the green wave coordination design scheme as C, taking into account the existence of green wave bandwidth. Define a positive number M that is greater than or equal to C;

[0049] Determine the minimum non-zero phase difference upshift tolerance of the coordinated path set and downward allowance The size is as follows:

[0050] (a) If Calculation in the coordination path chain Phase difference shift tolerance bottleneck set The minimum allowable phase difference shift for the coordinated path set at an intersection is calculated using the following formula:

[0051]

[0052] Determine if it is possible to reduce the set Intersection phase difference to improve coordinated path chain The green wave bandwidth is as follows:

[0053] like This indicates that the set cannot be reduced at this time. Phase difference at the intersection, therefore for coordinating path chains At intersection I j Let the non-zero phase difference shift tolerance be: And return to S305 to recalculate the set. The minimum non-zero phase difference allowance for upward and downward shifts in each coordinated path chain and coordinated path set;

[0054] like This indicates that the set can be reduced at this time. Phase difference at intersection, intersection I j The phase difference adjustment amount is:

[0055]

[0056] And return to S301 to perform green wave bandwidth optimization in the r-th round and t+1th iteration;

[0057] (b) If Calculation in the coordination path chain Phase difference downshift tolerance bottleneck set The minimum allowable phase difference shift for the coordinated path set at an intersection is calculated using the following formula:

[0058]

[0059] Determine if adding a set is possible Intersection phase difference to improve coordinated path chain The green wave bandwidth is as follows:

[0060] like This indicates that the set cannot be increased at this time. Phase difference at the intersection, therefore for coordinating path chains At intersection I j Let the non-zero phase difference downshift tolerance be: And return to S305 to recalculate the set. The minimum non-zero phase difference allowance for upward and downward shifts in each coordinated path chain and coordinated path set;

[0061] like This indicates that the set can be increased at this time. Phase difference at intersection, intersection I j The phase difference adjustment amount is:

[0062]

[0063] Then return to S301 to perform green wave bandwidth optimization in the r-th round and t+1th iteration.

[0064] As a preferred technical solution, the green wave bandwidth optimization termination condition is:

[0065] (a) If r = R max The optimization ends when the maximum number of rounds for optimizing the green wave bandwidth of the control area has been reached.

[0066] (b) If r≠R max ,for satisfy That is, the allowable upward and downward shift of phase difference for all intersections is 0. At this point, there is no room for further optimization of the phase difference for all intersections, and the optimization ends.

[0067] The condition for continuing the first green wave bandwidth optimization in the (r+1)th round is: if r≠R max , Make or That is, there exists an intersection where the phase difference upward or downward shift tolerance is not zero.

[0068] As a preferred technical solution, the final result of the phase difference adjustment amount for each intersection is as follows:

[0069] Determine intersection I j The final phase difference O j The calculation formula is as follows:

[0070]

[0071] In the formula, mod represents the modulo operation.

[0072] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0073] (1) This invention proposes a method for multi-round optimization of the green wave bandwidth of each level of coordinated path chain by comprehensively analyzing the allowable upward and downward shift of the phase difference of each signal intersection, while ensuring that the green wave bandwidth remains unchanged throughout the entire process. This method can simultaneously optimize multiple coordinated path chains within the control area.

[0074] (2) The design method provided by the present invention can maximize the green wave bandwidth of each level of the coordinated path chain without changing the common signal period, phase time, or phase sequence, by optimizing the phase difference of each intersection in multiple rounds, thereby further improving the overall green wave coordination control effect of the coordinated path chain. Attached Figure Description

[0075] Figure 1 This is a flowchart of a multi-round optimization method for green wave bandwidth of a coordinated path chain according to an embodiment of the present invention;

[0076] Figure 2 This is a schematic diagram illustrating the situation where the green wave bandwidth of the coordinated path chain reaches its limit according to an embodiment of the present invention;

[0077] Figure 3 This is a schematic diagram of the method for determining the phase difference adjustment amount at an intersection according to an embodiment of the present invention;

[0078] Figure 4 This is a schematic diagram illustrating the controlled object situation according to an embodiment of the present invention;

[0079] Figure 5 This is a schematic diagram of the signal timing scheme before phase difference optimization in an embodiment of the present invention;

[0080] Figure 6 This is a schematic diagram of the coordination path set for each round in an embodiment of the present invention;

[0081] Figure 7 This is the time interval diagram for the first round of green wave bandwidth optimization in this embodiment of the invention;

[0082] Figure 8 This is the time interval diagram for the second round of green wave bandwidth optimization in this embodiment of the invention;

[0083] Figure 9 This is the time interval diagram for the third round of green wave bandwidth optimization in this embodiment of the invention;

[0084] Figure 10 This is the time-distance diagram for the fourth round of green wave bandwidth optimization in this embodiment of the invention;

[0085] Figure 11 This is the time interval diagram for the fifth round of green wave bandwidth optimization in this embodiment of the invention;

[0086] Figure 12 This is a schematic diagram of the signal timing scheme after phase difference optimization according to an embodiment of the present invention. Detailed Implementation

[0087] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative effort are within the scope of protection of the present application.

[0088] Example 1

[0089] like Figure 1 As shown, this embodiment provides a multi-round optimization method for green wave bandwidth of coordinated path chains. Assuming that several coordinated path chains within a certain control area are used as the optimization targets for green wave coordination design in that area, the method includes the following steps:

[0090] S1 determines the coordination phase of each coordinated path chain and the start and end times of its green light at the intersections it passes through.

[0091] S2 determines the maximum number of rounds for green wave bandwidth optimization for each coordination path chain and the coordination path set for each round based on the number of coordination paths contained in each coordination path chain, and determines the maximum number of rounds for green wave bandwidth optimization in the control area.

[0092] S3 calculates the allowable upward and downward shift of the phase difference at each intersection for each round of the coordinated path set, and determines the objects and amounts of the phase difference adjustment at the intersections.

[0093] S4 outputs the final result of the phase difference adjustment for each intersection.

[0094] Preferably, step S1 specifically includes:

[0095] Based on the initial green wave coordination design scheme, determine each coordination path chain L. i At intersection I j Coordination phase k (i,j) And the corresponding initial green light start time T GS(i,j) and the initial green light end time point T GE(i,j) .

[0096] Preferably, step S2 specifically includes:

[0097] The coordination path chains L i Green wave bandwidth optimization maximum number of rounds r maxi For N i -1, N i To coordinate path chain L i The number of intersections included.

[0098] Furthermore, the coordination path set for each round is the optimization object for each coordination path chain in that round to perform green wave bandwidth optimization. Specifically, it defines the coordination path chain L. i The p-th coordination path is a coordination path chain. The first coordination path in the process, for a given coordination path chain L i , with r coordinated path chains L i In continuous N i -r coordination path chains It serves as the optimization target for the r-th round of green wave bandwidth optimization.

[0099] Furthermore, the maximum number of rounds for optimizing the green wave bandwidth of the control area is R. max =max{r maxi}

[0100] Preferably, step S3 specifically includes:

[0101] The specific steps for performing the r-th round and t-th optimization are as follows:

[0102] S301: Determine the start and end times of the green light.

[0103] Determine each coordination path chain L i At intersection I j Coordination phase k (i,j) Green light start time and the end time of the green light The calculation formula is as follows:

[0104]

[0105]

[0106] In the formula, T GS(i,j) T GE(i,j) Each coordination path chain L i At intersection I j Coordination phase k (i,j) The initial start time and the initial end time of the green light; Intersection I j The phase difference adjustment amount, where during the first optimization in the first round.

[0107] S302: Determine the start and end times of the green wave band.

[0108] Determine each coordination path chain At intersection I j Green wave start time and the end time of the green wave

[0109] S303: Determine the allowable upward and downward shift of the phase difference.

[0110] Determine each coordination path chain At intersection I j Phase difference shift tolerance and downward allowance The calculation formula is as follows:

[0111]

[0112]

[0113] Define the coordination path chain China satisfies and The intersections form coordinated path chains. Phase difference shift tolerance bottleneck set and the bottleneck set of phase difference downshift tolerance satisfy and The intersections form coordinated path chains. Phase difference shift tolerance non-bottleneck set Phase difference downshift tolerance non-bottleneck set

[0114] Furthermore, determine the coordinated path set at intersection I. j Phase difference shift tolerance and downward allowance The calculation formula is as follows:

[0115]

[0116]

[0117] Definition satisfies and The intersections respectively constitute the coordinated path set, phase difference upward shift tolerance, and bottleneck set. and the bottleneck set of phase difference downshift tolerance

[0118] S304: Divide the set of coordinated path chains according to whether the green wave bandwidth has reached the limit value.

[0119] Based on whether the green wave bandwidth of each coordinated path chain has reached its limit, define the set of coordinated path chains whose green wave bandwidth has reached its limit. Set of coordinated path chains where green wave bandwidth has not reached its limit The condition under which the green wave bandwidth reaches its limit is:

[0120] For coordinating path chains intersection like Intersection Simultaneously, within the bottleneck set of phase difference and downward displacement tolerance of the coordinated path set, and at the intersection In the coordination path chain Within the bottleneck sets of phase difference upward shift tolerance and phase difference downward shift tolerance, such as Figure 2 As shown, the coordinated path chain is now in effect. The green wave bandwidth reaches its limit. Specifically, if the intersection... Coordinate path chains at the same intersection The green wave bandwidth is the intersection bandwidth. Coordinate phase time.

[0121] S305: Determine whether to terminate green wave bandwidth optimization and determine the phase difference adjustment object and adjustment amount.

[0122] Based on the allowable phase difference shifts up and down and the division of the coordinated path chain set, the specific details are as follows:

[0123] Case 1: If That is, all coordinated path chains in the r-th round and t-th green wave bandwidth optimization. The green wave bandwidth has reached its limit. At this point, it is necessary to determine whether the green wave bandwidth optimization termination condition is met. If it is met, the green wave bandwidth optimization ends; otherwise, the (r+1)th round of the first green wave bandwidth optimization continues. The green wave bandwidth optimization termination condition is:

[0124] (a) If r = R max Once the maximum number of rounds for optimizing the green wave bandwidth of the control area has been reached, the optimization ends.

[0125] (b) If r≠R max ,for satisfy That is, the allowable upward and downward shift of phase difference for all intersections is 0. At this point, there is no room for further optimization of the phase difference for all intersections, and the optimization ends.

[0126] definition At this time, intersection I j Phase difference adjustment amount Enter S4 to calculate the final phase difference.

[0127] Furthermore, the condition for continuing the first green wave bandwidth optimization in the (r+1)th round is: if r ≠ R max , Make or If the phase difference tolerance for upward or downward shift at an intersection is not zero, then intersection I will not be considered again in this round. j Phase difference adjustment is performed at intersection I. j The phase difference adjustment amount is:

[0128]

[0129] Return to S301 to perform the first green wave bandwidth optimization in the (r+1)th round.

[0130] Scenario 2: If That is, a coordinated path chain exists in the r-th round and t-th green wave bandwidth optimization. The green wave bandwidth has not yet reached its limit, such as Figure 3 As shown, at this time, calculate intersection I. j The specific steps for adjusting the phase difference are as follows:

[0131] Determine the coordinated path chains for each green wave whose bandwidth has not yet reached its limit. Minimum non-zero phase difference upshift tolerance and downward allowance The calculation formula is as follows:

[0132]

[0133]

[0134] Furthermore, determine the minimum non-zero phase difference upshift tolerance for the coordinated path set. and downward allowance The calculation formula is as follows:

[0135]

[0136]

[0137] Define the minimum non-zero phase difference upshift tolerance of the coordinated path set at this time. To coordinate the path chain At the intersection Phase difference shift tolerance Minimum non-zero phase difference downshift tolerance for coordinated path sets To coordinate the path chain At the intersection Phase difference downshift tolerance

[0138] Define the common signal period of the green wave coordination design scheme as C, taking into account the existence of green wave bandwidth. Define a positive number M that is greater than or equal to C.

[0139] Determine the minimum non-zero phase difference upshift tolerance of the coordinated path set and downward allowance The size is as follows:

[0140] (a) If Calculation in the coordination path chain Phase difference shift tolerance bottleneck set The minimum allowable phase difference shift for the coordinated path set at an intersection is calculated using the following formula:

[0141]

[0142] Determine if it is possible to reduce the set Intersection phase difference to improve coordinated path chain The green wave bandwidth is as follows:

[0143] like This indicates that the set cannot be reduced at this time. Phase difference at the intersection, therefore for coordinating path chains At intersection I j Let the non-zero phase difference shift tolerance be: And return to S305 to recalculate the set. The minimum non-zero phase difference allowance for upward and downward shift of each coordination path chain and coordination path set.

[0144] like This indicates that the set can be reduced at this time. Phase difference at intersection, intersection I j The phase difference adjustment amount is:

[0145]

[0146] Furthermore, return to S301 to perform the green wave bandwidth optimization in the r-th round and the (t+1)-th iteration.

[0147] (b) If Calculation in the coordination path chain Phase difference downshift tolerance bottleneck set The minimum allowable phase difference shift for the coordinated path set at an intersection is calculated using the following formula:

[0148]

[0149] Determine if adding a set is possible Intersection phase difference to improve coordinated path chain The green wave bandwidth is as follows:

[0150] like This indicates that the set cannot be increased at this time. Phase difference at the intersection, therefore for coordinating path chains At intersection I j Let the non-zero phase difference downshift tolerance be: And return to S305 to recalculate the set. The minimum non-zero phase difference allowance for upward and downward shift of each coordination path chain and coordination path set.

[0151] like This indicates that the set can be increased at this time. Phase difference at intersection, intersection I j The phase difference adjustment amount is:

[0152]

[0153] Furthermore, return to S301 to perform the green wave bandwidth optimization in the r-th round and the (t+1)-th iteration.

[0154] Preferably, step S4 specifically includes:

[0155] Determine intersection I j The final phase difference O j The calculation formula is as follows:

[0156]

[0157] In the formula, mod represents the modulo operation.

[0158] Example 2

[0159] This embodiment describes the invention in detail by performing multiple rounds of coordinated path chain green wave bandwidth optimization on a control area of ​​a north-south arterial road containing 7 intersections. The phase sequence, phase duration, phase difference, and distance between adjacent intersections of the initial green wave coordination design scheme for each intersection are as follows: Figure 4 As shown, the green wave is designed for a speed of 60 km / h and a common signal period C of 162 s.

[0160] S1 determines the coordination phase of each coordinated path chain and the start and end times of its green light at the intersections it passes through.

[0161] In this embodiment, coordinated path chains L1 and L2 are used to coordinate the traffic flow from the south entrance of intersection I1 to the west exit of intersection I7, and the traffic flow from the north entrance of intersection I7 to the south exit of intersection I1, respectively. The coordinated phases of each coordinated path chain at each intersection and the corresponding green light start and end times are as follows: Figure 5 As shown.

[0162] S2 determines the maximum number of rounds for green wave bandwidth optimization for each coordination path chain and the coordination path set for each round based on the number of coordination paths contained in each coordination path chain, and determines the maximum number of rounds for green wave bandwidth optimization in the control area.

[0163] In this embodiment, coordination path chains L1 and L2 each contain 6 coordination paths, therefore, their maximum number of rounds for green wave bandwidth optimization is 6 rounds. Thus, the maximum number of rounds R for green wave bandwidth optimization in the control area is... max It consists of 6 rounds, and the coordination path sets for each round are as follows: Figure 6 As shown.

[0164] S3 calculates the allowable upward and downward shifts of the phase difference at each intersection for each round of the coordinated path set, and determines the objects and amounts of the phase difference adjustment at the intersections.

[0165] In this embodiment, a positive number M = C is used in the calculation process.

[0166] In this embodiment, the first round of optimization is performed below, with the phase difference adjustment for each intersection being 0s. According to... Figure 7 a) The phase difference allowances for each coordinated path chain and coordinated path set at each intersection are calculated as shown in Table 1.

[0167]

[0168] Table 1. Allowable Upward and Downward Shifts of Phase Difference in the First Round and First Optimization

[0169] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase shift allowance at intersection I6 Therefore, coordinate the path chain Phase difference shift tolerance bottleneck set Minimum allowable phase difference downshift of its coordinated path set Therefore, the I2 phase difference adjustment amount at the intersection Similarly Everything else remains the same.

[0170] In this embodiment, the second optimization in the first round will be performed below. According to... Figure 7 b) Calculate the phase difference upward and downward allowable values ​​for each coordinated path chain and coordinated path set at each intersection, as shown in Table 2.

[0171]

[0172] Table 2. Allowable Upward and Downward Shift of Phase Difference in the Second Optimization of the First Round

[0173] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase shift allowance at intersection I7 Therefore, coordinate the path chain Phase difference shift tolerance bottleneck set Minimum allowable phase difference downshift of its coordinated path set Therefore, the I2 phase difference adjustment amount at the intersection Similarly Everything else remains the same.

[0174] In this embodiment, the third optimization in the first round will be performed below. According to... Figure 7 c) The phase difference allowances for each coordinated path chain and coordinated path set at each intersection are calculated as shown in Table 3.

[0175]

[0176] Table 3. Phase difference upward and downward tolerances in the third optimization of the first round.

[0177] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase difference downshift allowance at intersection I7 Therefore, the bottleneck set for coordinating the phase difference downshift tolerance of the path chain Minimum allowable phase shift of its coordinated path set phase difference Therefore, the phase difference adjustment amount at intersection I3 Similarly Everything else remains the same.

[0178] In this embodiment, the fourth optimization in the first round will be performed below. According to... Figure 7 d) The phase difference allowances for each coordinated path chain and coordinated path set at each intersection are calculated as shown in Table 4.

[0179]

[0180] Table 4. Phase difference upward and downward tolerances in the 4th optimization of the 1st round.

[0181] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Because of R max ≠1, Make At this point, the green wave bandwidth optimization termination condition is not met, and the phase difference adjustment amount for each intersection is the same as that in the third optimization of the first round.

[0182] In this embodiment, the second round of the first optimization is performed below. According to... Figure 8 a) The phase difference allowances for each coordinated path chain and coordinated path set at each intersection are calculated as shown in Table 5.

[0183]

[0184] Table 5. Phase difference upward and downward tolerances in the first optimization of the second round.

[0185] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase difference downshift allowance at intersection I1 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference Therefore, the phase difference adjustment amount at intersection I3 Similarly Everything else remains the same.

[0186] In this embodiment, the second round of optimization will be performed below. According to... Figure 8 b) Calculate the phase difference upward and downward allowable values ​​for each coordinated path chain and coordinated path set at each intersection, as shown in Table 6.

[0187]

[0188] Table 6. Allowable Upward and Downward Shifts of Phase Difference in the Second Round and Second Optimization

[0189] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase difference downshift allowance at intersection I2 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference Therefore, the phase difference adjustment amount of intersection I1 Similarly Everything else remains the same.

[0190] In this embodiment, the second round and third optimization will be performed below. According to... Figure 8 c) Calculate the phase difference allowances for each coordinated path chain and coordinated path set at each intersection, as shown in Table 7.

[0191]

[0192] Table 7. Allowable Upward and Downward Shifts of Phase Difference in the Second and Third Optimization Rounds

[0193] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase shift allowance at intersection I1 Therefore, coordinate the path chain Phase difference shift tolerance bottleneck set Minimum allowable phase difference downshift of its coordinated path set Therefore, the phase difference adjustment amount at intersection I6 Everything else remains the same.

[0194] In this embodiment, the fourth optimization in the second round will be performed below. According to... Figure 8 d) Calculate the phase difference upshift and downshift tolerances for each coordinated path chain and coordinated path set at each intersection, as shown in Table 8.

[0195]

[0196] Table 8. Phase difference upward and downward tolerances in the 4th optimization of the 2nd round.

[0197] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Because of R max ≠2, Make At this point, the green wave bandwidth optimization termination condition is not met, and the phase difference adjustment amount for each intersection is the same as that in the second round and the third optimization.

[0198] In this embodiment, the third round of the first optimization is performed below. According to... Figure 9 a) The phase difference allowances for each coordinated path chain and coordinated path set at each intersection are calculated as shown in Table 9.

[0199]

[0200]

[0201] Table 9. Phase difference upward and downward tolerances in the first optimization of the third round.

[0202] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowable upward and downward shifts for each coordination path chain and coordination path set can be obtained. because To coordinate the path chain Phase difference downshift allowance at intersection I3 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference Therefore, the phase difference adjustment amount at intersection I5 Everything else remains the same.

[0203] In this embodiment, the second optimization in the third round will be performed below. According to... Figure 9 b) Calculate the phase difference upward and downward allowable values ​​for each coordinated path chain and coordinated path set at each intersection, as shown in Table 10.

[0204]

[0205] Table 10. Phase difference upward and downward tolerances in the second optimization of the third round.

[0206] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowable upward and downward shifts for each coordination path chain and coordination path set can be obtained. because To coordinate the path chain Phase difference downshift allowance at intersection I5 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference It is not possible to improve the coordinated path chain by increasing the phase difference between I2 and I3 at the intersection. The green wave bandwidth.

[0207] make Calculate the set again The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase difference downshift allowance at intersection I6 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference Therefore, the phase difference adjustment amount at intersection I3 Similarly Everything else remains the same.

[0208] In this embodiment, the third round and third optimization will be performed below. According to... Figure 9 c) Calculate the phase difference upward and downward allowable values ​​for each coordinated path chain and coordinated path set at each intersection, as shown in Table 11.

[0209]

[0210] Table 11. Phase difference upward and downward tolerances in the third round and third optimization.

[0211] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Because of R max ≠3, Make At this point, the green wave bandwidth optimization termination condition is not met, and the phase difference adjustment amount for each intersection is the same as that in the second optimization of the third round.

[0212] In this embodiment, the fourth round of the first optimization is performed below. According to... Figure 10 a) The phase difference allowances for each coordinated path chain and coordinated path set at each intersection are calculated as shown in Table 12.

[0213]

[0214]

[0215] Table 12. Phase difference upward and downward tolerances in the first optimization of the fourth round.

[0216] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase difference downshift allowance at intersection I5 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference Therefore, the phase difference adjustment amount at intersection I3 Everything else remains the same.

[0217] In this embodiment, the second optimization in the fourth round will be performed below. According to... Figure 10 b) Calculate the phase difference upward and downward allowable values ​​for each coordinated path chain and coordinated path set at each intersection, as shown in Table 13.

[0218]

[0219]

[0220] Table 13. Phase difference upward and downward tolerances in the second optimization of the fourth round.

[0221] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase difference downshift allowance at intersection I3 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference It is not possible to improve the coordinated path chain by increasing the phase difference between I5 and I6 at the intersection. The green wave bandwidth.

[0222] make Calculate the set again The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase shift allowance at intersection I6 Therefore, coordinate the path chain Phase difference shift tolerance bottleneck set Minimum allowable phase difference downshift of its coordinated path set Therefore, the phase difference adjustment amount at intersection I4 Everything else remains the same.

[0223] In this embodiment, the third optimization in the fourth round will be performed below. According to... Figure 10 c) Calculate the phase difference allowances for each coordinated path chain and coordinated path set at each intersection, as shown in Table 14.

[0224]

[0225]

[0226] Table 14. Phase difference upward and downward tolerances in the third optimization of the fourth round.

[0227] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Because of R max ≠4, Make At this point, the green wave bandwidth optimization termination condition is not met, and the phase difference adjustment amount for each intersection is the same as that in the second optimization of the fourth round.

[0228] In this embodiment, the 5th round of the 1st optimization is performed below. According to Figure 11 a) The phase difference allowances for each coordinated path chain and coordinated path set at each intersection are calculated as shown in Table 15.

[0229]

[0230] Table 15. Phase difference upward and downward tolerances in the first optimization of the fifth round.

[0231] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Compute set The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase shift allowance at intersection I4 Therefore, coordinate the path chain Phase difference shift tolerance bottleneck set Minimum allowable phase difference downshift of its coordinated path set It is not possible to improve the coordinated path chain by reducing the I2 phase difference at the intersection. The green wave bandwidth.

[0232] make Calculate the set again The minimum non-zero phase difference allowances for upward and downward shifts in each coordination path chain and coordination path set can be known. because To coordinate the path chain Phase difference downshift allowance at intersection I2 Therefore, coordinate the path chain Phase difference downshift tolerance bottleneck set Minimum allowable phase shift of its coordinated path set phase difference Therefore, the phase difference adjustment amount at intersection I3 Everything else remains the same.

[0233] In this embodiment, the 5th round, 2nd optimization is performed below. According to... Figure 11 b) Calculate the phase difference upward and downward allowable values ​​for each coordinated path chain and coordinated path set at each intersection, as shown in Table 16.

[0234]

[0235] Table 16. Phase difference upward and downward tolerances in the second optimization of the fifth round.

[0236] Based on the assessment, the set of coordinated path chains for green wave bandwidth has not reached its limit. Because of R max ≠5, for satisfy That is, the allowable upward and downward phase difference of all intersections is 0, which satisfies the green wave bandwidth optimization termination condition, and the optimization ends. Then, proceed to S4 to calculate the final phase difference.

[0237] S4 outputs the final result of the phase difference adjustment for each intersection.

[0238] In this embodiment, the final phase differences at each intersection are 0s, 0s, 10s, 159s, 6s, 156s, and 0s, respectively. The signal timing scheme after phase difference optimization is as follows: Figure 12 As shown, comparing the green wave bandwidth of each segment of the coordinated path chain L1 and L2 before and after optimization, the optimized scheme improved the bandwidth by 6.42% compared to the unoptimized scheme.

[0239] In this embodiment, the green wave bandwidth of each round of coordinated path set before and after optimization is shown in Table 17. The optimized scheme improved by 0.18%, 3.06%, 3.90%, 4.60%, and 6.37% respectively compared with the unoptimized scheme.

[0240]

[0241] Table 17. Green wave bandwidth of each round of coordinated path set (s)

[0242] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0243] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A multi-round optimization method for green wave bandwidth of a coordinated path chain, characterized in that, Includes the following steps: Determine the coordination phase and the start and end times of the green lights at the intersections traversed by each coordination path chain; Based on the number of coordination paths contained in each coordination path chain, determine the maximum number of rounds for green wave bandwidth optimization for each coordination path chain and the coordination path set for each round, and determine the maximum number of rounds for green wave bandwidth optimization in the control area. For each round of coordinated path sets, calculate the allowable upward and downward shifts of the phase difference at each intersection in each round, and determine the objects and amounts of phase difference adjustment at intersections, specifically: Perform the t-th optimization in the r-th round: S301. Determine the start and end times of the green light: Determine each coordination path chain At the intersection Coordination phase Green light start time and the end time of the green light The calculation formula is as follows: ； ； In the formula, , Each coordination path chain At the intersection Coordination phase The initial green light start time and the initial green light end time; Intersection The phase difference adjustment amount, where during the first optimization in the first round. ; S302. Determine the start and end times of the green wave band: Determine each coordination path chain At the intersection Green wave start time and the end time of the green wave ; S303. Determine the allowable upward and downward shift of the phase difference: Determine each coordination path chain At the intersection Phase difference shift tolerance and downward allowance The calculation formula is as follows: ； ； Define the coordination path chain China satisfies and The intersections form coordinated path chains. Phase difference shift tolerance bottleneck set and the bottleneck set of phase difference downshift tolerance ;satisfy and The intersections form coordinated path chains. Phase difference shift tolerance non-bottleneck set Phase difference downshift tolerance non-bottleneck set ; Determine the coordinated path set at the intersection Phase difference shift tolerance and downward allowance The calculation formula is as follows: ； ； Definition satisfies and The intersections respectively constitute the coordinated path set, phase difference upward shift tolerance, and bottleneck set. and the bottleneck set of phase difference downshift tolerance ; S304. Divide the coordinated path chain set according to whether the green wave bandwidth has reached the limit value: Based on whether the green wave bandwidth of each coordinated path chain has reached its limit, define the set of coordinated path chains whose green wave bandwidth has reached its limit. Set of coordinated path chains where green wave bandwidth has not reached its limit ; S305. Determine whether to terminate green wave bandwidth optimization and determine the phase difference adjustment target and adjustment amount; Output the final result of the phase difference adjustment for each intersection.

2. The method for multi-round optimization of green wave bandwidth in a coordinated path chain according to claim 1, characterized in that, The determination of the coordination phase and the start and end times of the green lights at the intersections traversed by each coordination path chain is specifically as follows: Based on the initial green wave coordination design scheme, determine each coordination path chain. At the intersection Coordination phase And the corresponding initial green light start time. and the end time of the initial green light .

3. The method for multi-round optimization of green wave bandwidth in a coordinated path chain according to claim 1, characterized in that, Coordination path chains Green wave bandwidth optimization maximum number of rounds for , To coordinate the path chain The number of intersections included; The coordination path set for each round is the optimization object for each coordination path chain in that round for green wave bandwidth optimization. Specifically, it defines the coordination path chain. The p-th coordination path is a coordination path chain. The first coordination path in the middle, for a certain coordination path chain , with r coordinated path chains continuous A chain of coordination paths As the optimization target for the r-th round of green wave bandwidth optimization; The maximum number of rounds for optimizing the green wave bandwidth in the control area is: .

4. The method for multi-round optimization of green wave bandwidth in a coordinated path chain according to claim 1, characterized in that, In step S304, the condition for the green wave bandwidth to reach its limit value is: For coordinating path chains intersection ,like , , Intersection Simultaneously, within the bottleneck set of phase difference and downward displacement tolerance of the coordinated path set, and at the intersection In the coordination path chain Within the bottleneck sets of phase difference upward shift tolerance and phase difference downward shift tolerance, the coordinated path chain is as follows. The green wave bandwidth reaches its limit; if the intersection Coordinate path chains at the same intersection The green wave bandwidth is the intersection bandwidth. or Coordinated phase time.

5. The method for multi-round optimization of green wave bandwidth in a coordinated path chain according to claim 1, characterized in that, In step S305, the determination of terminating green wave bandwidth optimization and determining the phase difference adjustment target and adjustment amount specifically includes: Based on the allowable up and down shifts in phase difference and the set of coordinated path chains, the following classifications are included: Case 1: If That is, all coordinated path chains in the r-th round and t-th green wave bandwidth optimization. The green wave bandwidth has reached its limit. At this point, it is determined whether the green wave bandwidth optimization termination condition is met. If it is met, the green wave bandwidth optimization ends. At this time, the intersection Phase difference adjustment amount The process jumps to the step of outputting the final result of the phase difference adjustment for each intersection; if the condition is not met, no further adjustments are made to the intersection. Phase difference adjustment is performed at the intersection. The phase difference adjustment amount is: Return to S301 to continue the process. The first round of green wave bandwidth optimization; Scenario 2: If That is, there exists a coordinated path chain in the r-th round and t-th green wave bandwidth optimization. The green wave bandwidth has not yet reached its limit; at this time, the intersection is calculated. The specific steps for adjusting the phase difference are as follows: Determine the coordinated path chains for each green wave whose bandwidth has not yet reached its limit. Minimum non-zero phase difference upshift tolerance and downward allowance The calculation formula is as follows: ； ； Determine the minimum non-zero phase difference upshift tolerance for the coordinated path set. and downward allowance The calculation formula is as follows: ； ； Define the minimum non-zero phase difference upshift tolerance of the coordinated path set at this time. To coordinate the path chain At the intersection Phase difference shift tolerance Minimum non-zero phase difference downshift tolerance of the coordinated path set To coordinate the path chain At the intersection Phase difference downshift tolerance ; Define the common signal period of the green wave coordination design scheme as C, taking into account the existence of green wave bandwidth. , Define a positive number M that is greater than or equal to C; Determine the minimum non-zero phase difference upshift tolerance of the coordinated path set and downward allowance The size is as follows: (a) If Calculate the path chain in the coordination path Phase difference shift tolerance bottleneck set The minimum allowable phase difference shift for the coordinated path set at an intersection is calculated using the following formula: ； Determine if it is possible to reduce the set Intersection phase difference to improve coordinated path chain The green wave bandwidth is as follows: like This indicates that the set cannot be reduced at this time. Phase difference at the intersection, therefore for coordinating path chains At the intersection Let the non-zero phase difference shift tolerance be: And return to S305 to recalculate the set. The minimum non-zero phase difference allowance for upward and downward shifts in each coordinated path chain and coordinated path set; like This indicates that the set can be reduced at this time. Phase difference at intersection, intersection The phase difference adjustment amount is: ； And return to S301 to proceed with the first... Round Secondary green wave bandwidth optimization; (b) If Calculate the path chain in the coordination path Phase difference downshift tolerance bottleneck set The minimum allowable phase difference shift for the coordinated path set at an intersection is calculated using the following formula: ； Determine if adding a set is possible Intersection phase difference to improve coordinated path chain The green wave bandwidth is as follows: like This indicates that the set cannot be increased at this time. Phase difference at the intersection, therefore for coordinating path chains At the intersection Let the non-zero phase difference downshift tolerance be: And return to S305 to recalculate the set. The minimum non-zero phase difference allowance for upward and downward shifts in each coordinated path chain and coordinated path set; like This indicates that the set can be increased at this time. Phase difference at intersection, intersection The phase difference adjustment amount is: ； And return to S301 to proceed with the first... Round Secondary green wave bandwidth optimization.

6. The method for multi-round optimization of green wave bandwidth in a coordinated path chain according to claim 5, characterized in that, The termination condition for the green wave bandwidth optimization is: (a) If The optimization ends when the maximum number of rounds for optimizing the green wave bandwidth of the control area has been reached. (b) If ,for ,satisfy , When the allowable upward and downward shifts of the phase difference for all intersections are both 0, there is no further room for optimization of the phase difference for all intersections, and the optimization ends. Continue with the first The condition for the first green wave bandwidth optimization in the first round is: if , Make or This means that the phase difference at the intersection has an upward or downward allowable range that is not zero.

7. The method for multi-round optimization of green wave bandwidth in a coordinated path chain according to claim 1, characterized in that, The final result of the phase difference adjustment for each intersection is as follows: Determine the intersection final phase difference The calculation formula is as follows: ； In the formula, mod represents the modulo operation.

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