Bus signal priority compensation control method and system based on green wave band protection

Abstract

The invention provides a bus signal priority compensation control method and system based on green wave band protection. The method comprises the steps that trunk line green wave coordination parameters are acquired; collecting road traffic information, traffic signal state information and vehicle running state information; judging whether a bus priority triggering condition is met or not according to the collected information; when the trigger condition is met, executing a bus priority strategy, and determining additional phase time increased by the strategy in the current signal period; executing a phase compensation mechanism which specifically comprises the following steps: judging whether a non-coordinated phase has enough compensation capability in a current period; if there is enough compensation capability, compensation of the additional phase time is completed in the current period; and if the compensation capability is not enough, performing partial compensation by using the available compensation time of the non-coordinated phase in the current period, and distributing the residual disturbance time to the subsequent one or more periods to gradually complete compensation. According to the invention, the operation efficiency of buses and the overall traffic capacity of urban traffic are improved.

Description

Technical Field

[0001] This invention relates to the field of traffic signal control and optimization technology, specifically providing a bus signal priority compensation control method and system based on green wave protection. Background Technology

[0002] With the acceleration of urbanization, urban traffic congestion has become increasingly serious. As an important means of alleviating traffic pressure, improving the operational efficiency of public transportation is of great significance. Traditional traffic signal control systems usually take into account the passage needs of ordinary vehicles, failing to fully meet the priority passage needs of public transportation vehicles. This results in limited operational efficiency of public transportation vehicles in urban traffic, making it difficult to guarantee punctuality, and consequently affecting the attractiveness and competitiveness of public transportation.

[0003] Existing bus signal priority control methods primarily grant priority to buses by adjusting signal phase timing and setting dedicated bus signal phases. However, these methods have some limitations in practical applications. On the one hand, simply granting priority to buses may significantly interfere with other traffic flows, leading to a decrease in the overall traffic efficiency of the intersection. On the other hand, while considering bus priority, existing methods neglect the coordinated control of the green wave, causing "disruptions" in the green wave and affecting traffic flow. Summary of the Invention

[0004] To overcome the above-mentioned defects, the present invention is proposed to provide a solution or at least a partial solution to the above-mentioned problems.

[0005] In a first aspect, the present invention provides a bus signal priority compensation control method based on green wave protection, comprising the following steps: acquiring trunk green wave coordination parameters; collecting road traffic information, traffic signal status information, and vehicle operating status information; determining whether bus priority triggering conditions are met based on the collected information; when the triggering conditions are met, executing a bus priority strategy, and determining the additional phase time added by the strategy within the current signal cycle. The additional phase time refers to the extended green light time or early red light time generated when implementing the bus priority strategy; the phase compensation mechanism includes: determining whether the non-coordinated phases in the current cycle have sufficient compensation capacity; if sufficient compensation capacity is available, then completing the adjustment of the additional phase time in the current cycle. If there is insufficient compensation capacity, partial compensation will be performed using the available compensation time of the non-coordinated phase in the current cycle, and the remaining disturbance time will be allocated to one or more subsequent cycles to gradually complete the compensation.

[0006] Preferably, determining whether the bus priority triggering condition is met specifically includes: determining whether the bus's off-duty time exceeds a first preset value; determining whether the remaining time of the downstream green wave window exceeds a second preset value; and determining to execute the bus priority strategy when the off-duty time exceeds the first preset value and the remaining time of the downstream green wave window exceeds the second preset value.

[0007] Preferably, the execution of the bus priority strategy and the determination of the additional phase time added by the bus priority strategy within the current signal cycle specifically includes: predicting the estimated time when the bus will arrive at the stop line at the intersection; determining the green light extension time or the red light early termination time based on the signal phase state corresponding to the predicted time: if the predicted green light running time is sufficient for the bus to pass, the green light extension time is zero, i.e., no additional phase time is generated; if the predicted green light running time is insufficient for the bus to pass, the green light extension time is determined, and this green light extension time is used as the additional phase time; if the predicted red light running time is the first part of the red light, the green light time of the previous phase is extended, and this extended time is used as the additional phase time; if the predicted red light running time is the second part of the red light, the red light early termination time is determined, and this red light early termination time is used as the additional phase time.

[0008] Preferably, determining whether the non-coordinated phases in the current cycle have sufficient compensation capability specifically includes: calculating the sum of the green light redundancy times of all non-coordinated phases in the current cycle. ;like If so, it is determined that the company has sufficient compensation capacity; if If so, it is determined that the company does not have sufficient compensation capacity.

[0009] Preferably, the sum of green light redundancy times for all non-coordinated phases within the current cycle is calculated. Specifically, this includes: for any non-coordinated phase The green light redundancy time for the current cycle is defined as: ,in, This is the original green light duration for the non-coordinated phase. The minimum green light duration required to meet traffic safety and minimum clearance requirements; the total compensation time available for all non-coordinated phases within the current cycle is: ,in, This represents the set of all non-coordinated phases involved in the compensation. The number indicating the non-coordinated phase; This indicates the current signal control cycle number.

[0010] Preferably, when sufficient compensation capability is available, indicating that the green light redundancy time of the non-coordinated phase within the same cycle is sufficient, compensation is completed within the current cycle by compressing the green light time of the non-coordinated phase. Therefore, the total compensation time is: .

[0011] Preferably, when there is insufficient compensation capacity, the remaining disturbance time is allocated to one or more subsequent cycles to gradually complete the compensation, specifically including: when When this occurs, it indicates that the green light redundancy time for the non-coordinated phase within the same cycle is insufficient, and the compensation time for the current cycle is... The remaining scrambling time is: A cross-cycle compensation strategy is adopted to distribute the remaining disturbance time to one or more subsequent cycles for gradual digestion, namely: until the remaining disturbance time satisfies ;in, Indicates the number of subsequent cycles used to complete the cross-cycle compensation; This indicates the subsequent compensation cycle number; The number indicating the non-coordinated phase; This indicates the current signal control cycle number.

[0012] Preferably, it further includes: setting an elastic threshold for the trunk green wave band. The elastic threshold The perturbation range of green wave coordination parameters used to characterize bus priority control is expressed as the proportion of allowed green wave bandwidth compression; when implementing the bus priority strategy, the elastic threshold is used. As a constraint, the degree to which bus priority compresses the green wave bandwidth is limited.

[0013] Preferably, it further includes: detecting the green wave throughput within the statistical period; if the decrease in the green wave throughput does not exceed a set range, keeping the green wave band elastic threshold unchanged; if the decrease in the green wave throughput exceeds a set range, reducing the elastic threshold α to tighten the compression restriction of the green wave bandwidth on subsequent bus priority.

[0014] Secondly, the present invention provides a bus signal priority compensation control system based on green wave protection, comprising: The vehicle-mounted layer includes onboard units for buses and onboard units for private vehicles, which are deployed in buses and private vehicles to collect and output vehicle operating status information. The roadside layer consists of roadside units and signal controllers, and is deployed at the intersection. The roadside units collect traffic flow, queue length, road saturation and downstream traffic status of the road segment, and communicate with the on-board unit via V2I. The signal controllers collect the signal status information of the intersection and execute the issued signal priority and compensation control commands. The cloud-based decision-making layer includes an edge computing unit, which communicates with the vehicle-mounted unit via V2N and connects to the roadside unit via a wired / wireless network to receive vehicle-mounted and roadside data. The cloud-based decision-making layer is configured to execute the bus signal priority compensation control method based on green wave protection as described in any one of claims 1 to 9. The execution and control layer, including the signal controller and downstream linkage interface, is deployed at the intersection and connected to the signal controller via a wired / wireless network. It is used to execute the bus priority signal adjustment commands issued by the edge computing unit, and at the same time, it links the downstream intersection to ensure the continuity of the green wave and the bus priority effect. The feedback and system optimization layer is integrated into the edge computing unit. It communicates with the vehicle unit, roadside unit and signal controller to collect operational performance data, dynamically optimize the green wave bandwidth and elastic threshold, and feed the optimization results back to the edge computing unit and signal controller.

[0015] The beneficial effects of this invention are as follows: 1. This invention constructs a two-layer compensation mechanism of "priority compensation during the current cycle + multi-cycle recursion across cycles." After bus priority is implemented, it first determines whether the green light redundancy time of the non-coordinated phase in the current cycle is sufficient to compensate for the additional phase time caused by priority. If sufficient, compensation is completed in the current cycle without affecting subsequent cycles; if insufficient, the remaining disturbance time is allocated to one or more subsequent cycles for gradual digestion. This mechanism avoids the new phase imbalance problem that may be caused by fixed one-time compensation in the next cycle in the prior art, realizes the smooth digestion of disturbance, and ensures the stable operation of the signal control system.

[0016] 2. This invention introduces a flexible threshold for the green wave band as a quantitative constraint on the permissible range of green wave coordination parameters for bus priority control. This flexible threshold can be preset according to the accuracy requirements of trunk line coordination control, the saturation level of road sections, and the reliability requirements of bus operation. When implementing the bus priority strategy, it serves as a constraint condition, limiting the maximum disturbance amplitude of bus priority to the green wave system and achieving a dynamic balance between bus priority demand and green wave coordination protection.

[0017] 3. This invention detects the green wave throughput rate within a statistical period. When the green wave throughput rate decreases beyond a set range, it automatically reduces the elastic threshold and tightens the triggering conditions for subsequent bus priority. This feedback adjustment mechanism enables the system to adaptively adjust the protection boundary based on actual operating results. While ensuring bus priority needs, it prevents the cumulative disturbance to the green wave system from exceeding acceptable limits, thus improving the long-term operational stability of the system.

[0018] 4. This invention forms a complete closed loop from priority triggering, priority execution, disturbance compensation, boundary protection to effect feedback by setting comprehensive triggering conditions (dual determination of bus off-duty time and remaining time of downstream green wave window), green wave friendly priority strategy (adaptive priority control based on phase state), dual-layer compensation mechanism (current cycle compensation + cross-cycle multi-cycle recursive compensation), elastic threshold protection boundary and feedback adjustment, and downstream linkage mild priority, etc., realizing the systematic collaborative optimization of bus priority and green wave coordination.

[0019] 5. This invention, while ensuring the priority needs of public transportation, minimizes the impact on trunk line green wave coordination through compensation mechanisms and flexible threshold protection. When bus delays are not effectively alleviated, a lighter priority is implemented at downstream intersections, expanding single-point priority into localized corridor-style continuous priority. This effectively improves the punctuality and operational reliability of public transportation while ensuring the overall stability of green wave coordination. Attached Figure Description

[0020] The disclosure of this invention will become more readily understood with reference to the accompanying drawings. It will be readily understood by those skilled in the art that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. Wherein: Figure 1 This is a flowchart illustrating a bus signal priority compensation control method based on green wave protection according to an embodiment of the present invention. Figure 2 This is a flowchart of a bus signal priority compensation control system based on green wave protection according to an embodiment of the present invention. Figure 3 This is a schematic diagram illustrating the applicable scenario of the bus signal priority compensation control method based on green wave protection according to an embodiment of the present invention. Detailed Implementation

[0021] Some embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0022] Example 1 like Figure 1-3 As shown, this invention provides a bus signal priority compensation control method based on green wave protection, comprising the following steps: Step S1: Obtain the trunk line green wave coordination parameters.

[0023] In this embodiment, the trunk green wave coordination parameters include: common period. Phase difference ,bandwidth ).

[0024] Set the initial elastic threshold for the trunk green wave band Green band elastic threshold This parameter characterizes the perturbation range of existing green wave coordination parameters for bus priority control. It can be preset based on the accuracy requirements of trunk line coordination control, road segment saturation levels, and bus operation reliability needs. Elastic threshold. This represents the percentage of green wave bandwidth compression allowed.

[0025] Step S2: Collect road traffic information, traffic signal status information, and vehicle operation status information.

[0026] In this embodiment, real-time data collection of road, traffic signal, and vehicle operating status is based on On-Board Unit (OBU) and Roadside Unit (RSU) devices. The collected road traffic information includes traffic density, saturation, and downstream road segment traffic status. Traffic signal status information includes the current signal phase, remaining green light time for the current phase, remaining red light time for the current phase, cycle start and end times, and phase switching times. Vehicle operating status information includes bus location, vehicle speed, direction of travel, travel plan information, bus off-duty time, and the operating status of other vehicles.

[0027] Step S3: Determine whether the bus priority triggering conditions are met based on the collected information; In this embodiment, the determination can be made according to the following logic: (1) If the off-duty time of the bus does not exceed the first set value, it is considered that there is no obvious priority at present, and the original green wave coordination control is maintained. (2) If the remaining time of the downstream green wave window is too short, i.e. it does not exceed the second set value, the bus after priority will still have difficulty entering the downstream effective green wave passage area and will not trigger priority.

[0028] If all the above conditions are met, the bus priority strategy will be implemented; otherwise, the original green wave coordination and control scheme will be maintained and the next testing cycle will begin.

[0029] Step S4: When the triggering condition is met, execute the bus priority strategy and determine the additional phase time added by the strategy within the current signal cycle. The additional phase time The extended green light time or earlier red light time resulting from the implementation of the public transport priority strategy.

[0030] Specifically, it includes: Step S41: Predict the estimated time when the bus will arrive at the stop line at the intersection; Step S42: Determine the green light extension time or the red light early termination time based on the signal phase state corresponding to the predicted time. Step S421: If it is predicted that when the bus arrives at the intersection, it is during the green light running time, and the remaining green light time is sufficient for the bus to pass through the intersection, then the bus will pass through the intersection directly. That is, the green light extension time is zero, and no additional phase time is generated.

[0031] In this embodiment, "satisfying the bus's passage through the intersection" means that the remaining time of the current green light is greater than or equal to the minimum passage time required for a bus to travel from its current position to the stop line and pass through the conflict point. This can be expressed as: in, Indicates the remaining green light time for the current signal phase; This indicates the minimum travel time required for a bus to reach the stop line from its current location and pass through the intersection conflict point. This indicates the distance from the current position of the bus to the stop line; This indicates the current operating speed or predicted average speed of the bus. This indicates the time required for a bus to pass the stop line and leave the intersection.

[0032] Step S422: If the predicted green light running time is not sufficient for the bus to pass, then determine the green light extension time and use the green light extension time as the additional phase time to allow the bus to pass through the intersection.

[0033] In this embodiment, when a bus arrives at the intersection, if the remaining green light time for the current phase is insufficient for the bus to pass the stop line, a green light extension time needs to be determined. The green light extension time is expressed as follows: Among them, when hour, ;when When green light extension is used, the smaller value between the compensation time required for public transportation and the maximum permissible green light extension time is taken. This indicates the time required for a bus to reach the stop line from the current moment. This indicates the time required for a bus to pass the stop line. This indicates the maximum permissible extension time for the green light.

[0034] Step S423: If it is predicted that the bus will arrive at the intersection during the red light phase, the green light time of the previous phase will be extended, and the extended time will be used as the additional phase time to allow it to pass through the intersection. In this embodiment, when a bus arrives at an intersection, if the current phase is the initial red light phase, and the green light time of the previous phase is extended before the red light phase is executed to allow the bus to pass the stop line, then the green light extension time needs to be determined. The green light extension time is expressed as follows: in, Indicates the remaining time for the current red light phase; This indicates the scheduled duration of the next green light phase after the current red light phase ends.

[0035] The aforementioned green light extension time should meet the following principles: not less than the compensation time required for buses to complete their passage; not exceeding the maximum extension time allowed by the current phase; and not exceeding the green wave protection constraints.

[0036] Step 424: If it is predicted that the bus will arrive at the intersection during the later part of the red light cycle, then determine the early red light end time and use this early red light end time as the additional phase time to allow it to pass through the intersection.

[0037] In this embodiment, when a bus arrives at an intersection, if the current phase is the latter part of a red light cycle, and a red light early termination strategy is adopted to allow the bus to pass the stop line before the red light phase is executed, then the red light early termination time needs to be determined. The red light early termination time is expressed as: in, This indicates the scheduled duration of the next green light phase after the current red light phase ends. This indicates the maximum allowable early red light termination time by the system.

[0038] The aforementioned early red light termination time must meet the following constraints: the minimum green light time of the truncated phase has been met; the yellow light and all-red light times meet safety requirements; the early red light termination amount does not exceed the adjustable range under the green wave protection constraint; and it does not cause irreversible disturbance to the coordination offset of downstream intersections.

[0039] In this embodiment, the cloud-based decision layer predicts the estimated time when the bus will arrive at the intersection stop line based on the bus's current location, operating speed, stop time at the bus stop, and distance to the intersection; then, by combining the current signal phase and phase switching sequence, it determines the phase state corresponding to the arrival of the bus.

[0040] Step S5: Execute the phase compensation mechanism, which specifically includes: Determine whether the non-coordinated phases within the current cycle have sufficient compensation capabilities; If sufficient compensation capacity is available, the additional phase time can be completed within the current cycle. Compensation; If there is insufficient compensation capacity, partial compensation will be performed using the available compensation time of the non-coordinated phase in the current cycle, and the remaining disturbance time will be allocated to one or more subsequent cycles to gradually complete the compensation.

[0041] In this embodiment, to reduce the impact of priority control on the green wave operation of trunk lines, a signal phase compensation mechanism is further implemented. Assume that bus priority is in the current cycle. The additional phase time caused by the internal For any non-coordinated phase The green light redundancy time for the current cycle is defined as: Therefore, the total compensation time available for all non-coordinated phases within the current period is: in, This is the original green light duration for the non-coordinated phase. The minimum green light duration is designed to meet both traffic safety and minimum clearance requirements. This represents the set of all non-coordinated phases involved in the compensation; The number indicating the non-coordinated phase; This indicates the current signal control cycle number.

[0042] Scenario 1: Sufficient green light redundancy time for non-coordinated phases within the same cycle.

[0043] If there is sufficient green light redundancy time for non-coordinated phases within the same cycle, the phase disturbances caused by bus priority will be compensated by compressing the green light time of non-coordinated phases within this cycle, thereby maintaining the public cycle as much as possible. Phase difference and bandwidth No significant changes occurred.

[0044] when When this indicates that the green light redundancy time for the non-coordinated phase is sufficient within the same cycle, compensation is completed within the current cycle by compressing the green light time for the non-coordinated phase. Therefore, the total compensation time is: Scenario 2: Insufficient green light redundancy time in the same cycle for non-coordinated phases.

[0045] If the green light redundancy time for non-coordinated phases is insufficient within the same cycle, a cross-cycle compensation strategy is adopted to distribute the remaining disturbances to one or more subsequent cycles for gradual digestion, so as to avoid causing new operational risks by drastically compressing the phase within a single cycle.

[0046] when When this occurs, it indicates that the green light redundancy time for the non-coordinated phase within the same cycle is insufficient, and the compensation time for the current cycle is... The remaining scrambling time is: A cross-cycle compensation strategy is adopted to distribute the remaining disturbance time across one or more subsequent cycles for gradual digestion, namely: Until the remaining disturbance time is satisfied ; in, Indicates the number of subsequent cycles used to complete the cross-cycle compensation; Indicates the subsequent compensation cycle number; The number indicating the non-coordinated phase; This indicates the current signal control cycle number.

[0047] Step S6: Detect whether the green wave pass rate has decreased, and determine whether to adjust the green wave band elastic threshold. In this embodiment, the green wave throughput rate can be expressed as the proportion of vehicles operating at the recommended green wave speed that successfully pass through multiple intersections consecutively within a statistical period. The green wave throughput rate can be expressed as: in, This is expressed as the green wave pass rate; This indicates the number of vehicles that successfully passed through multiple intersections consecutively while operating at the recommended green wave speed within the statistical period. This represents the total number of vehicles operating at the recommended green wave speed within the statistical period.

[0048] If the test results show that the green wave transmittance has not decreased significantly, or the decrease has not exceeded the set range, then the green wave band elastic threshold will be maintained. The threshold remains unchanged; if the detection results indicate that the green wave transmittance decreases beyond the set range, then the elastic threshold for the green wave band will be adjusted. Adjustments were made to tighten the triggering conditions for subsequent bus priority, thereby reducing the cumulative disturbance of subsequent priority control to the green wave system.

[0049] In addition, the green band elastic threshold The initial value can be 5%, and the allowable threshold for the green wave throughput can be 10%; however, this invention is not limited to the above values ​​and can be adjusted according to the road grade, public transport reliability requirements, and road saturation level.

[0050] Step S7: After completing the priority control and compensation at the current intersection, check whether the bus off-duty time has been alleviated, and determine whether the system should link with downstream intersections to implement light priority within their safety thresholds.

[0051] If the detection results indicate that the bus off-duty time has been alleviated, the current control mode is maintained and the control results for this round are output; if the detection results indicate that the bus off-duty time has not been effectively alleviated, it is further determined whether to link with downstream intersections and implement mild priority within their safety threshold.

[0052] In this embodiment, "light priority at downstream intersections" means that, without significantly disrupting the existing phase safety and coordination control requirements of downstream intersections, the green light extension and red light termination are implemented at the associated intersections through which the target bus subsequently passes.

[0053] By introducing a downstream linkage mechanism, this invention can extend single-point priority to local corridor-style continuous priority, which can further improve the punctuality and operational reliability of buses while ensuring the overall stability of green wave coordination.

[0054] Example 2 A bus signal priority compensation control system based on green wave protection includes: The vehicle layer includes on-board units (OBUs), specifically on-board units for buses and private vehicles. Deployed in buses and private vehicles, these units collect and output vehicle operation status information. This information includes vehicle location, speed, direction of travel, bus off-duty time, and driving plan. The information is exchanged bidirectionally with roadside units (RSUs) and edge computing units (MECs) via V2X to enable vehicle status uploading and signal command reception. The roadside layer consists of roadside units (RSUs) and signal controllers, which are deployed at the intersection. The RSUs collect traffic flow, queue length, road saturation, and downstream traffic status of the road segment, and communicate with the on-board units (OBUs) via V2I. The signal controllers collect the signal status information of the intersection and execute the signal priority and compensation control commands issued by the edge computing unit (MEC). The cloud-based decision-making layer includes an edge computing unit (MEC), which communicates with the on-board unit (OBU) via V2N and connects to the roadside unit (RSU) and signal controller via wired / wireless networks to receive on-board and roadside data. The cloud-based decision-making layer is configured as the bus signal priority compensation control method based on green wave protection. The execution and control layer, including the signal controller and downstream linkage interface, is deployed at the intersection to execute the bus priority signal adjustment commands issued by the edge computing unit (MEC). At the same time, it links with the downstream intersection to ensure the continuity of the green wave and the bus priority effect. The feedback and system optimization layer is integrated into the edge computing unit (MEC). It communicates with the on-board unit (OBU), roadside unit (RSU), and signal controller to collect operational data, dynamically optimize the green wave bandwidth and elastic threshold, and feed the optimization results back to the edge computing unit (MEC) and signal controller.

[0055] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the original technical features, and the technical solutions resulting from these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A bus signal priority compensation control method based on green wave protection, characterized in that, Includes the following steps: Obtain the trunk line green wave coordination parameters; Collect road traffic information, traffic signal status information, and vehicle operation status information; Determine whether the bus priority triggering conditions are met based on the collected information; When the triggering condition is met, the bus priority strategy is executed, and the additional phase time added by the bus priority strategy within the current signal cycle is determined. The additional phase time The extended green light time or early red light time resulting from the implementation of the bus priority strategy; The phase compensation mechanism is implemented, specifically including: Determine whether the non-coordinated phases within the current cycle have sufficient compensation capabilities; If sufficient compensation capacity is available, the additional phase time can be completed within the current cycle. Compensation; If there is insufficient compensation capacity, partial compensation will be performed using the available compensation time of the non-coordinated phase in the current cycle, and the remaining disturbance time will be allocated to one or more subsequent cycles to gradually complete the compensation.

2. The method according to claim 1, characterized in that, The determination of whether the bus priority triggering condition is met specifically includes: Determine whether the bus's off-duty time exceeds a first set value; Determine whether the remaining time of the downstream green wave window exceeds the second preset value; When the off-duty time exceeds a first set value and the remaining time of the downstream green wave window exceeds a second set value, the bus priority strategy is determined to be implemented.

3. The method according to claim 1, characterized in that, The implementation of the bus priority strategy and the determination of the additional phase time added by the bus priority strategy within the current signal cycle specifically include: Predict the estimated time when buses will arrive at the stop line at the intersection; Based on the signal phase state corresponding to the predicted time, determine the green light extension time or the red light early termination time: If the predicted green light running time is sufficient for buses to pass, then the green light extension time is zero, meaning no additional phase time is generated. If the predicted green light running time is not sufficient for the bus to pass, then the green light extension time is determined and used as the additional phase time. If the prediction is that the red light is in the early stage, then the green light time of the previous phase is extended, and the extended time is used as the additional phase time. If the prediction indicates the period after the red light starts running, then the early red light termination time is determined, and this early red light termination time is used as the additional phase time.

4. The method according to claim 1, characterized in that, The determination of whether the non-coordinated phase in the current period has sufficient compensation capability specifically includes: Calculate the total green light redundancy time for all non-coordinated phases within the current cycle. ; like If so, it is determined that the company has sufficient compensation capacity; like If so, it is determined that the company does not have sufficient compensation capacity.

5. The method according to claim 4, characterized in that, Calculate the total green light redundancy time for all non-coordinated phases within the current cycle. Specifically, it includes: For any non-coordinated phase The green light redundancy time for the current cycle is defined as: in, This is the original green light duration for the non-coordinated phase. The minimum green light duration to meet traffic safety and minimum clearance requirements; The total compensation time available for all non-coordinated phases within the current period is: in, This represents the set of all non-coordinated phases involved in the compensation. The number indicating the non-coordinated phase. This indicates the current signal control cycle number.

6. The method according to claim 4, characterized in that, When sufficient compensation capacity is available, it indicates that the green light redundancy time for non-coordinated phases within the same cycle is sufficient. Therefore, compensation is completed within the current cycle by compressing the green light time for non-coordinated phases, resulting in a total compensation time of: 。 7. The method according to claim 4, characterized in that, When there is insufficient compensation capacity, the remaining disturbance time will be allocated to one or more subsequent cycles to gradually complete the compensation, specifically including: when When this occurs, it indicates that the green light redundancy time for the non-coordinated phase within the same cycle is insufficient, and the compensation time for the current cycle is... The remaining disturbance time is: A cross-cycle compensation strategy is adopted to distribute the remaining disturbance time across one or more subsequent cycles for gradual digestion, namely: Until the remaining disturbance time is satisfied ; in, This indicates the number of subsequent cycles used to complete the cross-cycle compensation. Indicates the subsequent compensation cycle number. The number indicating the non-coordinated phase. This indicates the current signal control cycle number.

8. The method according to claim 1, characterized in that, Also includes: Set the flexible threshold for the trunk green wave band The elastic threshold The parameter used to characterize the perturbable range of green wave coordination parameters for bus priority control is expressed as the proportion of green wave bandwidth compression allowed. When implementing the bus priority strategy, the elastic threshold is used. As a constraint, the degree to which bus priority compresses the green wave bandwidth is limited.

9. The method according to claim 8, characterized in that, Also includes: Detect the green wave pass rate within the statistical period; If the decrease in green wave pass rate does not exceed the set range, the green wave band elastic threshold remains unchanged; If the decrease in green wave pass rate exceeds a set range, then the elastic threshold is reduced. This is to tighten the compression restrictions on green wave bandwidth for subsequent bus priority.

10. A bus signal priority compensation control system based on green wave protection, characterized in that, include: The vehicle-mounted layer includes onboard units for buses and onboard units for private vehicles, which are deployed in buses and private vehicles to collect and output vehicle operating status information. The roadside layer consists of roadside units and signal controllers, and is deployed at the intersection. The roadside units collect traffic flow, queue length, road saturation and downstream traffic status of the road segment, and communicate with the on-board unit via V2I. The signal controllers collect the signal status information of the intersection and execute the issued signal priority and compensation control commands. The cloud-based decision-making layer includes an edge computing unit, which communicates with the vehicle-mounted unit via V2N and connects to the roadside unit via a wired / wireless network to receive vehicle-mounted and roadside data. The cloud-based decision-making layer is configured to execute the bus signal priority compensation control method based on green wave protection as described in any one of claims 1 to 9. The execution and control layer, including the signal controller and downstream linkage interface, is deployed at the intersection and connected to the signal controller via a wired / wireless network. It is used to execute the bus priority signal adjustment commands issued by the edge computing unit, and at the same time, it links the downstream intersection to ensure the continuity of the green wave and the bus priority effect. The feedback and system optimization layer is integrated into the edge computing unit. It communicates with the vehicle unit, roadside unit and signal controller to collect operational performance data, dynamically optimize the green wave bandwidth and elastic threshold, and feed the optimization results back to the edge computing unit and signal controller.

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