A lane-level average vehicle delay calculation method considering oversaturated residual queues

Abstract

The present application relates to a lane-level average vehicle delay calculation method that considers oversaturated residual queues, and relates to the technical field of intelligent traffic control. The method comprises the following steps: calculating the effective green light duration, signal cycle, average vehicle arrival rate, and saturation flow rate of target lane i; calculating the number of vehicles in the initial green light queue and the initial red light queue of lane i in the jth cycle; determining whether the current traffic state is oversaturated; when the traffic state is unsaturated, calculating the lane-level average vehicle delay in the unsaturated state using the total vehicle delay in a single cycle, and then completing the calculation; when the traffic state is oversaturated, calculating the minimum number of signal cycles required for the rear vehicle in lane i to leave the intersection at the initial green light moment in the jth cycle, and calculating the lane-level average vehicle delay, and then completing the calculation. The present application has the effect of fully considering the accumulation or dissipation of oversaturated residual queues on a cycle-by-cycle basis.

Description

Technical Field

[0001] The present application relates to the technical field of intelligent traffic control, and in particular to a lane-level vehicle average delay calculation method considering oversaturated remaining queues. Background Art

[0002] In recent years, the continuous growth of urban motor vehicle ownership and increasing transportation demand have led to increasingly serious traffic congestion on urban roads, especially at intersections. As key nodes in the urban road network, the efficiency of intersections directly impacts the operational quality of the entire transportation system. Reasonable signal control strategies play a vital role in alleviating intersection congestion and improving road capacity.

[0003] Currently, intersection signal control methods are primarily optimized based on parameters such as traffic flow, saturation, and queue length to improve capacity and reduce vehicle delays. However, traditional intersection delay calculation methods mostly assume an unsaturated state and fail to fully account for the accumulation of residual queues in oversaturated conditions. In real-world traffic environments, particularly during peak hours, some intersections experience persistent oversaturation, resulting in queues that cannot be fully dissipated within a single signal cycle, but instead accumulate or dissipate cycle by cycle.

[0004] Existing research often requires deriving queue lengths when calculating delays. Due to a lack of queue length data from monitoring equipment, some methods rely solely on indirect means to estimate this metric, which affects calculation accuracy. Other studies, while equipped with queue length data, fail to fully utilize this information, using it only as an auxiliary parameter rather than a core calculation basis. This results in methods being less adaptable to oversaturated traffic conditions. Overall, existing research has limitations in addressing traffic characteristics under oversaturated conditions, making it difficult to accurately characterize the dynamic evolution of queue lengths. Summary of the Invention

[0005] In order to fully consider the accumulation or dissipation of the oversaturated residual queue on a cycle-by-cycle basis, the present application provides a lane-level average vehicle delay calculation method that considers the oversaturated residual queue.

[0006] This application provides a lane-level average vehicle delay calculation method considering oversaturated remaining queues, which adopts the following technical solutions:

[0007] A lane-level average vehicle delay calculation method considering oversaturated residual queues includes the following steps:

[0008] Calculate the effective green light duration, signal cycle, average vehicle arrival rate, and saturation flow rate of target lane i;

[0009] Calculate the number of vehicles queuing at the initial green light and the number of vehicles queuing at the initial red light for lane i in the jth cycle;

[0010] Determine whether the current traffic state is oversaturated;

[0011] When the traffic state is unsaturated, the total vehicle delay of lane i in the jth cycle is calculated, and the lane-level average vehicle delay in the unsaturated state is calculated using the total vehicle delay of a single cycle, and the calculation ends.

[0012] When the traffic state is oversaturated, calculate the minimum number of signal cycles required for the rear vehicle in lane i to leave the intersection at the initial green light moment of the jth cycle, and calculate the number of vehicles in the initial red light queue and the number of vehicles in the initial green light queue in other signal cycles relative to the current signal cycle within the minimum number of signal cycles;

[0013] The total vehicle delay within the minimum signal cycle required for the rear vehicle of the green light queue to leave the road condition in the oversaturated state is calculated, as well as the lane-level vehicle delay. The calculation is then terminated.

[0014] By adopting the above technical solution, the accuracy is improved by judging the oversaturation state and selecting different calculation models. When the traffic state is unsaturated, a single-cycle delay is used, and when the traffic state is oversaturated, a multi-cycle cumulative delay is used. At the same time, a complete lane-level delay calculation process is provided, covering both unsaturated and oversaturated traffic states, suitable for dynamic signal control scenarios.

[0015] Preferably, the calculation to obtain the effective green light duration, signal cycle, average vehicle arrival rate, and saturation flow rate of the target lane i comprises the following steps:

[0016] Set the relevant parameters during vehicle driving, including vehicle length l, following distance And the minimum safety distance minGap;

[0017] Obtain the signal cycle of lane i from the signal timing plan , Green light display duration , yellow light duration Hourly traffic flow and signal loss time L;

[0018] Calculate the effective green light duration of lane i ; Effective green light duration of lane i Equal to the green light display time Plus the yellow light duration Then subtract the signal loss time L;

[0019] Calculate the average vehicle arrival rate of lane i ; Average vehicle arrival rate Hourly traffic volume Divide by 3600 s / h;

[0020] Calculate the saturation flow rate of lane i ; Saturation flow rate Equal to the following distance The reciprocal of .

[0021] By adopting the above technical solution, the effective green light duration, signal cycle, average vehicle arrival rate, and saturation flow rate of target lane i can be obtained. By calculating the effective green light duration, invalid time can be eliminated to accurately reflect the traffic capacity of lane i. By calculating the saturation flow rate, the theoretical upper limit of lane i can be reflected based on the following distance.

[0022] Preferably, the calculation to obtain the number of vehicles in the initial queue of the green light and the number of vehicles in the initial queue of the red light for lane i in the jth cycle comprises the following steps:

[0023] If the maximum queue length of lane i in the jth cycle Greater than average vehicle length The sum of the minimum safety distance minGap, the number of vehicles queuing at the initial green light of lane i in the jth cycle is Equal to the maximum queue length Divide by the sum of the average vehicle length l and the minimum safety distance minGap;

[0024] If the maximum queue length of lane i in the jth cycle If the number of vehicles queuing at the initial green light of lane i in the jth cycle is less than or equal to the sum of the average vehicle length l and the minimum safety distance minGap, then Equal to the average vehicle arrival rate and non-effective green light duration The product of the non-effective green light duration Equal to the signal period Subtract the effective green light duration ;

[0025] The number of vehicles queuing at the initial stage of the red light Equal to the number of vehicles queuing at the initial green light Subtract the average vehicle arrival rate and non-effective green light duration and ensure that the result is not less than zero.

[0026] By adopting the above technical solution, the number of vehicles in the initial queue of the green light and the number of vehicles in the initial queue of the red light in lane i in the jth cycle under different conditions can be obtained.

[0027] Preferably, the determining whether the current traffic state is an oversaturated state comprises the following steps:

[0028] If the lane has an effective green light time in the cycle Longer than the time it takes for the vehicle queue to clear , then it is determined that lane i is in an unsaturated state in the jth cycle;

[0029] If the lane has an effective green light time in the cycle Less than or equal to the vehicle queue clearing time , then lane i is determined to be in an oversaturated state in the jth cycle.

[0030] By adopting the above technical solution, by comparing and , which can clearly define the oversaturation threshold, avoid misjudgment, and ensure the reliability of the signal optimization strategy.

[0031] As a preference, in the unsaturated state, the total vehicle delay of lane i in the jth cycle is It is the sum of the trapezoidal shadow area during the red light period and the triangle shadow area during the green light period. The specific formula is: .

[0032] By adopting the above technical solution, the red light delay (trapezoidal area) reflects the backlog of vehicles, and the green light delay (triangular area) reflects the dissipation process, and then the total vehicle delay in lane i in the jth cycle is calculated under the unsaturated state.

[0033] Preferably, the lane-level average vehicle delay in an unsaturated state is calculated using the total vehicle delay in a single cycle. The lane-level average vehicle delay of lane i is the ratio of the total vehicle delay in lane i in the jth cycle to the single cycle flow rate, and the formula is: .

[0034] By adopting the above technical solution, the calculation of lane-level average vehicle delay under unsaturated conditions can be achieved.

[0035] Preferably, the calculation of obtaining the minimum number of signal cycles required for the rear vehicle in lane i to leave the intersection at the initial green light moment in the jth cycle, and calculating the number of vehicles in the initial red light queue and the number of vehicles in the initial green light queue in other cycles within the minimum number of signal cycles, comprises the following steps:

[0036] Calculate the minimum number of signal cycles N required for the last vehicle in the initial green light queue for lane i in the jth cycle to leave the intersection. The minimum number of signal cycles N required for the last vehicle in the initial green light queue for lane i in the jth cycle to leave the intersection is equal to the number of vehicles in the initial green light queue for lane i in the jth cycle divided by the product of the saturation flow rate and the effective green light duration, and round the calculated result upwards.

[0037] Calculate the number of vehicles queuing at the initial red light in lane i during the j+1th cycle , through the formula ;

[0038] Calculate the number of vehicles queuing at the initial green light of lane i in the j+1th cycle , through the formula .

[0039] By adopting the above technical solution, the theoretical minimum dissipation practice can be obtained by calculating the minimum number of signal cycles, and then the queue accumulation effect can be captured through dynamic updating.

[0040] Preferably, the method of calculating the total vehicle delay within the minimum signal cycle required for the rear vehicle of the queue to leave the road condition at the initial stage of the green light under the oversaturated state, and calculating the lane-level vehicle average delay, comprises the following steps:

[0041] Based on whether the nth cycle is in an oversaturated state or an unsaturated state, the total vehicle delay of lane i in the nth cycle is The calculation formula is: ;

[0042] All lane-level vehicles are delayed It is equal to the sum of the total delays of N vehicles within the minimum signal cycle number, divided by the total number of vehicles arriving within N within the minimum signal cycle number, through the formula .

[0043] By adopting the above technical solution, the calculation of lane-level average vehicle delay can be achieved.

[0044] In summary, this application provides at least one of the following beneficial technical effects: By dynamically determining undersaturated and oversaturated states and employing single-cycle or multi-cycle delay models, it effectively addresses the large error issues inherent in traditional methods in oversaturated scenarios. A threshold determination based on queue clearing time ensures the scientific nature of signal timing optimization and traffic control strategies. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a flow chart of an embodiment of the present application;

[0046] Figure 2 This is an illustration of the scene in an unsaturated state;

[0047] Figure 3 This is a scenario diagram of the cycle-by-cycle accumulation of the remaining queue in the oversaturated state;

[0048] Figure 4 This is a diagram of the scenario where the remaining queue in the oversaturated state dissipates cycle by cycle;

[0049] Figure 5 This is an illustration of the scene in an oversaturated state. DETAILED DESCRIPTION

[0050] The following is combined with Figure 1-5 This application is described in further detail.

[0051] An embodiment of the present application discloses a lane-level average vehicle delay calculation method taking into account oversaturated remaining queues.

[0052] Reference Figure 1 A lane-level average vehicle delay calculation method considering oversaturated residual queues includes the following steps:

[0053] S1: Calculate the effective green light duration, signal cycle, average vehicle arrival rate and saturation flow rate of the target lane i;

[0054] S2: Calculate the number of vehicles queuing at the initial green light and the number of vehicles queuing at the initial red light for lane i in the jth cycle;

[0055] S3: Determine whether the current traffic state is an oversaturated state; if the traffic state is an unsaturated state, jump to step S4; if the traffic state is an oversaturated state, jump to step S6;

[0056] S4: Calculate the total vehicle delay of lane i in the jth cycle under the unsaturated state;

[0057] S5: Use the total vehicle delay in a single cycle to calculate the lane-level average vehicle delay in the unsaturated state. The calculation ends.

[0058] S6: Calculate the minimum number of signal cycles required for the rear vehicle to leave the intersection at the initial moment of obtaining the green light;

[0059] S7: Calculate the total vehicle delay within the minimum signal cycle required for the rear vehicle to leave the road condition at the initial green light stage under the oversaturated state, and calculate the lane-level vehicle average delay. The calculation ends.

[0060] In step S1, the effective green light duration, signal cycle, average vehicle arrival rate, and saturation flow rate of the target lane i are calculated, including the following steps:

[0061] S11: Set the relevant parameters during vehicle driving, including vehicle length l, following distance And the minimum safety distance minGap. In this embodiment, set l=5m, =2.86s, minGap=2m.

[0062] S12: Obtain the signal cycle of lane i from the signal timing plan , Green light display duration , yellow light duration Hourly traffic flow And signal loss time L. The signal loss time L includes the front loss time and the rear loss time. In this embodiment, set =100s, =20s , =3s, =360pcu / h, L=3s.

[0063] S13: Calculate the effective green light duration for lane i The effective green light duration of lane i Equal to the green light display time Plus the yellow light duration Then subtract the signal loss time L, that is .

[0064] In this embodiment, =20+3+3=20s.

[0065] By calculating the effective green light duration , which can eliminate invalid time and accurately reflect the traffic capacity of lane i.

[0066] S14: Calculate the average vehicle arrival rate of lane i Average vehicle arrival rate Hourly traffic volume Divide by 3600s / h, that is =0.1pcu / s.

[0067] S15: Calculate the saturation flow rate of lane i Saturation flow rate is the maximum number of vehicles that can pass through the lane per second, the saturation flow rate Equal to the following distance The reciprocal of =1 / 2.86≈0.35pcu / s.

[0068] By calculating the saturation flow rate Based on following distance , reflecting the theoretical upper limit of lane i.

[0069] In step S2, the number of vehicles in the initial queue of the green light and the number of vehicles in the initial queue of the red light for lane i in the jth cycle are calculated, and the following steps are also included:

[0070] S21: Calculate the number of vehicles queuing at the initial green light in lane i during the jth cycle If the maximum queue of lane i in cycle j is The length is greater than the sum of the average vehicle length l and the minimum safety distance minGap, that is When , it means that the queue length of this cycle can accommodate at least one vehicle. Then the number of vehicles queuing at the initial green light of lane i in the jth cycle is Equal to the maximum queue length Divide by the sum of the average vehicle length l and the minimum safety distance minGap, that is ;

[0071] Otherwise, proceed to step S22.

[0072] S22: Maximum queue length of lane i in cycle j Less than or equal to the sum of the average vehicle length l and the minimum safety distance minGap, that is , indicating that the queue length of this cycle is less than one vehicle, then the number of vehicles queuing at the initial green light is Equal to the average vehicle arrival rate and non-effective green light duration The product of , where the non-effective green light duration Equal to the signal period Subtract the effective green light duration ,Right now .

[0073] S23: Calculate the number of vehicles queuing at the initial red light Number of vehicles queuing at the initial red light Equal to the number of vehicles queuing at the initial green light Subtract the average vehicle arrival rate and non-effective green light duration The product of , and ensure that the result is not less than zero, that is .

[0074] In this embodiment, the maximum queue length of lane i in the jth cycle is set to is 145m, which is greater than the sum of the average vehicle length l and the minimum safety distance minGap, and then the process goes to step S21 and skips step S22. At this time, the vehicles in the initial queue of the green light , so that the number of vehicles queuing at the initial red light can be calculated .

[0075] In step S3, determining whether the current traffic state is an oversaturated state includes the following steps:

[0076] S31: Calculate the time it takes for lane i to clear the vehicle queue in the jth cycle Vehicle queue clearing time Equal to the number of vehicles queuing at the initial green light Divide by the net dissipation rate. The net dissipation rate represents the number of vehicles actually reduced in the queue per second, and the net dissipation rate is equal to the saturation flow rate. Subtract the average vehicle arrival rate .Right now .

[0077] In this embodiment, .

[0078] S32: When the lane has the effective green light time in the cycle Longer than the time it takes for the vehicle queue to clear When When the lane i is judged to be in an unsaturated state in the jth cycle, the process jumps to step S4; when the lane has an effective green light time of Less than or equal to the vehicle queue clearing time When , it is determined that lane i is in an oversaturated state in the jth cycle, and the process jumps to step S6.

[0079] In step S4, the total vehicle delay of lane i in the jth cycle under the unsaturated state is calculated, including the following:

[0080] refer to Figure 2 In the figure, the horizontal axis is time t, and the vertical axis is the number of vehicles in the queue Q. The red horizontal axis indicates that the time period is not a valid green light time. , the green horizontal axis indicates that the time period is the effective green light time At this time, the total vehicle delay in lane i in the jth cycle is It is the sum of the shadow area of ​​the trapezoid during the red light period and the shadow area of ​​the triangle during the green light period: .

[0081] In step S5, the lane-level average vehicle delay in the unsaturated state is calculated using the single-cycle total vehicle delay, and the calculation ends. At this point, the lane-level average vehicle delay in lane i is is the ratio of the total vehicle delay of lane i in the jth cycle to the single cycle flow, that is,

[0082] .

[0083] In step S6, the minimum number of signal cycles required for the rear vehicle of lane i to leave the intersection at the initial green light moment of the jth cycle is calculated, and the number of vehicles in the initial red light queue and the number of vehicles in the initial green light queue in other cycles within the minimum number of signal cycles are calculated, including the following steps:

[0084] S61: Calculate the minimum number of signal cycles N required for the vehicle at the end of the initial green light queue in lane i in the jth cycle to leave the intersection. The minimum number of cycles N required for the vehicle at the end of the initial green light queue in lane i in the jth cycle to leave the intersection is equal to the number of vehicles in the initial green light queue in lane i in the jth cycle. Divide by the saturation flow rate and effective green light duration The product of , and the calculated result is rounded up, that is .

[0085] In this embodiment, , that is, it takes 3 signal cycles for the last vehicle in lane i to leave the intersection at the beginning of the green light in the jth cycle.

[0086] S62: Calculate the number of vehicles queuing at the initial red light in lane i during the j+1th cycle The number of vehicles queuing at the initial red light in lane i during the j+1th cycle Equal to the number of vehicles queuing at the initial green light Add the number of newly arrived vehicles during the green light period and subtract the maximum number of vehicles that can be released during the green light period. The number of newly arrived vehicles during the green light period is the average vehicle arrival rate. and effective green light duration The maximum number of vehicles that can be released during the green light period is the saturation flow rate. Effective green light duration The product of . .

[0087] In this embodiment, .

[0088] S63: Calculate the number of vehicles queuing at the initial green light in lane i during the j+1th cycle The number of vehicles queuing at the initial green light in lane i during the j+1th cycle Equal to the number of vehicles queuing at the initial red light in lane i during the j+1th cycle Add the number of new vehicles arriving at the lane during the non-effective green light duration. The number of new vehicles arriving during the non-effective green light duration is the non-effective green light duration. and the average vehicle arrival rate The product of .

[0089] In this embodiment, .

[0090] S64: Calculate the number of vehicles queuing at the initial red light in lane i during the jth cycle =12.71pcu, the number of vehicles queuing at the initial red light in lane i during the j+1th cycle is 15.71 pcu; and the number of vehicles queuing at the initial green light in lane i during the jth cycle is =20.71, the number of vehicles queuing at the initial green light in lane i during the j+1th cycle is 23.71pcu, and so on, so that we can observe the reference Figure 3 and reference Figure 4 The overall remaining queued vehicles show a trend of periodic accumulation or dissipation. Figure 3 and Figure 4 The meaning of the horizontal and vertical coordinate parameters and Figure 2 same.

[0091] In step S7, the total vehicle delay within the minimum signal cycle required for the rear vehicle of the queue to leave the road condition at the initial stage of the green light under the oversaturation state is calculated, and the lane-level vehicle average delay is calculated. The calculation is completed, and the following steps are included:

[0092] S71: Calculate the total vehicle delay for multiple cycles within the minimum signal cycle required for the rear vehicle to leave the road condition at the initial green light stage, and the total vehicle delay for lane i in the nth cycle It is necessary to consider whether the nth cycle is in an oversaturated state.

[0093] In the unsaturated state , that is, when the queued vehicles can be completely dissipated in the current cycle, the total vehicle delay is the queuing delay during the red light period plus the dissipation delay during the green light period.

[0094] In saturated state , that is, the effective green light time is not enough to clear the queue, and the remaining vehicles will accumulate to the next cycle. The total vehicle delay is equal to the total delay of arriving vehicles in the cycle minus the delay corresponding to the theoretical maximum release volume during the green light period.

[0095] That is, the total vehicle delay in lane i in the nth cycle The calculation formula is:

[0096] .

[0097] Reference Figure 5 , in this embodiment, .

[0098] Similarly, as well as ,refer to Figure 3 or Figure 4 .

[0099] S72: Calculate the lane-level average vehicle delay under the oversaturation state. Lane-level average vehicle delay It is equal to the sum of the total delays of N vehicles within the minimum signal cycle number, divided by the total number of vehicles arriving within N within the minimum signal cycle number. .

[0100] In this embodiment, .

[0101] The present embodiment of the present invention proposes a lane-level average vehicle delay calculation method that considers oversaturated residual queues. The implementation principle is as follows: Accurate lane-level delay calculation is achieved by dynamically distinguishing between oversaturated and undersaturated traffic conditions. First, basic lane traffic indicators (such as effective green light duration and saturated flow rate) are calculated based on signal timing parameters and vehicle trajectory data. Second, the traffic state is dynamically determined based on the number of vehicles in the queue. If the queue can dissipate within the current green light, it is considered undersaturated, and a single-cycle delay is calculated. If the queue requires multiple cycles to dissipate, it is considered oversaturated. The minimum number of cycles N required for the last vehicle in the queue is calculated, and the delays of all vehicles within these N cycles are accumulated. Finally, the average vehicle delay value is output as the ratio of the total delay to the number of arriving vehicles. Compared to existing methods, this method can more accurately reflect the cycle-by-cycle accumulation or dissipation of queues under oversaturation, providing a scientific basis for traffic engineering decision-making. It can also be used to optimize signal control strategies to alleviate intersection congestion and improve the overall operational efficiency of the traffic system.

[0102] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.

Claims

1. A lane-level average vehicle delay calculation method considering oversaturated residual queues, characterized by: The following steps are involved: Calculate the effective green light duration, signal cycle, average vehicle arrival rate, and saturation flow rate of target lane i; Calculate the number of vehicles queuing at the initial green light and the number of vehicles queuing at the initial red light for lane i in the jth cycle; Determine whether the current traffic state is oversaturated; When the traffic state is unsaturated, the total vehicle delay of lane i in the jth cycle is calculated, and the lane-level average vehicle delay in the unsaturated state is calculated using the total vehicle delay of a single cycle, and the calculation ends. When the traffic state is oversaturated, calculate the minimum number of signal cycles required for the rear vehicle in lane i to leave the intersection at the initial green light moment of the jth cycle, and calculate the number of vehicles in the initial red light queue and the number of vehicles in the initial green light queue in other cycles within the specified number of signal cycles; Calculate the total vehicle delay within the minimum signal cycle required for the rear vehicle of the green light queue to leave the road condition in the oversaturated state, and calculate the lane-level vehicle delay, and then end the calculation; The calculation to obtain the effective green light duration, signal cycle, average vehicle arrival rate, and saturation flow rate of the target lane i includes the following steps: Set relevant parameters during vehicle driving, including vehicle length l, following distance h i And the minimum safety distance minGap; Obtain the signal cycle C of lane i from the signal timing plan i , Green light display duration G i , Yellow light duration Y i , hourly traffic flow Q i and signal loss time L; Calculate the effective green light duration g of lane i i ; Effective green light duration g for lane i i Equal to the green light display time G i Add the yellow light duration Y i Then subtract the signal loss time L; Calculate the average vehicle arrival rate a of lane i i ; Average vehicle arrival rate a i is the hourly traffic flow Q i Divide by 3600 s / h; Calculate the saturation flow rate s of lane i i ; Saturation flow rate s i Equal to the following distance h i The reciprocal of The calculation to obtain the number of vehicles in the initial queue of the green light and the number of vehicles in the initial queue of the red light for lane i in the jth cycle includes the following steps: If the maximum queue length ql of lane i in the jth cycle i,j If the length is greater than the sum of the average vehicle length l and the minimum safety distance minGap, then the number of vehicles queuing at the initial green light of lane i in the jth cycle is Equal to the maximum queue length ql i,j Divide by the sum of the average vehicle length l and the minimum safety distance minGap; If the maximum queue length ql of lane i in the jth cycle i,j If the number of vehicles queuing at the initial green light of lane i in the jth cycle is less than or equal to the sum of the average vehicle length l and the minimum safety distance minGap, then Equal to the average vehicle arrival rate a i and non-effective green light duration r i The non-effective green light duration r i Equal to the signal period C i Subtract the effective green light duration g i ; The number of vehicles queuing at the initial stage of the red light Equal to the number of vehicles queuing at the initial green light Subtract the average vehicle arrival rate a i and non-effective green light duration r i The product of and ensure that the result is not less than zero; The step of determining whether the current traffic state is an oversaturated state comprises the following steps: Calculate the vehicle queue clearing time of lane i in the jth cycle i,j , through the formula If the lane i has an effective green light time g in the jth cycle i Greater than the vehicle queue clearing time clear i,j , then it is determined that lane i is in an unsaturated state in the jth cycle; If the lane i has an effective green light time g in the jth cycle i Less than or equal to the vehicle queue clearing time clear i,j , then lane i is judged to be in an oversaturated state in the jth cycle; In the unsaturated state, the total vehicle delay in lane i during the jth cycle is the sum of the trapezoidal shadow area during the red light period and the triangle shadow area during the green light period. The specific formula is: The method of calculating the minimum number of signal cycles required for the rear vehicle of lane i to leave the intersection at the initial green light moment of the jth cycle, and calculating the number of vehicles in the initial red light queue and the number of vehicles in the initial green light queue in other cycles within the number of signal cycles, comprises the following steps: Calculate the number of signal cycles N required for the vehicle at the end of the initial green light queue of lane i in the jth cycle to leave the intersection. The number of signal cycles N required for the vehicle at the end of the initial green light queue of lane i in the jth cycle to leave the intersection is equal to the number of vehicles in the initial green light queue of lane i in the jth cycle. Divide by the saturation flow rate s i and effective green light duration g i The product of , and the calculated result is rounded up; Calculate the number of vehicles queuing at the initial red light in lane i during the j+1th cycle By formula Calculate the number of vehicles queuing at the initial green light of lane i in the j+1th cycle By formula The method of calculating the total vehicle delay within the minimum signal cycle required for the rear vehicle of the queue to leave the road condition at the initial stage of the green light under the oversaturated state and calculating the lane-level vehicle average delay includes the following steps: Based on whether the nth cycle is in an oversaturated state or an unsaturated state, the total vehicle delay D of lane i in the nth cycle i.n The calculation formula is: The lane-level vehicles are delayed by d i,j,N It is equal to the sum of the total delays of N vehicles within the signal cycle, divided by the total number of vehicles arriving within N within the signal cycle, through the formula 2. The lane-level average vehicle delay calculation method considering oversaturated remaining queues according to claim 1 is characterized by: The lane-level average vehicle delay in an unsaturated state is calculated using the total vehicle delay in a single cycle. The lane-level average vehicle delay of lane i is the ratio of the total vehicle delay in lane i in the jth cycle to the single cycle flow rate. The formula is:

Images