Fuel economy and delay joint optimization method in vehicle starting stage

Abstract

The invention relates to the technical field of intelligent traffic vehicle control, in particular to a fuel economy and delay joint optimization method in a vehicle starting stage. According to the method, based on a current vehicle starting scene, a multi-objective optimization function of a vehicle starting stage of a fuel consumption and delay model is constructed, and the multi-objective optimization function of the vehicle starting stage is set and comprises a fuel consumption minimization objective function and a delay minimization objective function; carrying out normalization on the multi-objective optimization function; setting constraint conditions of target optimization according to the vehicle starting scene; and solving the fuel consumption and delay model based on the constraint condition of the fuel consumption and delay model of the current vehicle starting scene to obtain the optimal acceleration of the vehicle at different moments in the vehicle starting stage. The invention focuses on a starting stage which has obvious influence on the fuel economy and the delay of the vehicle, and researches a method for realizing dual improvement of the fuel economy and the starting delay in the process, so that the control effect of the vehicle starting is improved.

Description

Technical Field

[0001] The present invention relates to the field of intelligent traffic vehicle control technology, and in particular to a method for jointly optimizing fuel economy and delay during a vehicle startup phase. Background Art

[0002] With the acceleration of urbanization, residents' travel needs are growing, resulting in a sharp increase in the number of vehicles in cities. Fuel consumption and traffic delays have become the focus of social attention. Therefore, how to effectively manage the urban transportation system and reduce fuel consumption and traffic delays has become an important research topic.

[0003] In urban traffic, the vehicle startup phase is a key factor affecting fuel efficiency and traffic flow. The startup phase of a vehicle often leads to higher fuel consumption and traffic delays. When the vehicle starts, the engine needs additional fuel to overcome inertia and start the cooler, especially during cold starts. When the engine is at a low temperature, additional fuel is needed to increase the engine's operating temperature, thereby improving its efficiency. In addition, frequent short-distance starts and stops will disrupt the normal rhythm of traffic flow and cause the transmission of congestion waves. The cumulative effect of such traffic delays may lead to serious traffic jams and further extend driving time. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problems of high fuel consumption and long traffic delay time when starting a vehicle.

[0005] In order to solve the above technical problems, the present invention provides a method for jointly optimizing fuel economy and delay in the vehicle startup phase, comprising the following steps:

[0006] Step S1: Divide the vehicle start scenario into two scenarios, namely, a single vehicle start scenario and a vehicle queue start scenario;

[0007] Step S2: Determine the fuel consumption and delay model, and set the multi-objective optimization function of the vehicle startup phase, including: fuel consumption minimization and delay minimization objective functions;

[0008] Step S3: performing normalization processing to convert the multi-objective function of step S2 into a single objective function;

[0009] Step S4: setting the constraint conditions for target optimization according to the vehicle start scenario. The single vehicle start scenario includes: acceleration constraint and road speed limit constraint; the queue start scenario includes: acceleration constraint, road speed limit constraint and front vehicle safety distance constraint;

[0010] Step S5: Solve the model of step S2 according to the constraint conditions and draw a vehicle trajectory diagram.

[0011] Preferably, if the vehicle startup scenario is a single vehicle startup scenario, a single vehicle fuel consumption minimization objective function and a single vehicle delay minimization objective function are constructed according to the road speed limit value, vehicle startup time, fuel consumption during the startup phase, instantaneous speed and acceleration of the vehicle, and the initial position and end position of the startup phase;

[0012] If the vehicle startup scenario is queued, the multi-vehicle fuel consumption minimization objective function and the multi-vehicle delay minimization objective function are constructed based on the road speed limit, the current total number of vehicles, the startup time of each vehicle, the fuel consumption during the startup phase, the instantaneous speed and acceleration, the initial position and the end position of the startup phase.

[0013] Preferably, the objective function for minimizing the fuel consumption of a single vehicle is:

[0014]

[0015] Among them, F1 is the objective function for minimizing the fuel consumption of a single vehicle, MOE e is the fuel consumption of the vehicle within Δt time, MOE e It is calculated by the VT-micro vehicle fuel consumption model, where T is the vehicle startup time, Δt is the preset time interval, e is a natural constant, and v t is the speed of the vehicle at time t, a t is the acceleration of the vehicle at time t, v t The jth power, for a t kth power, L j,k for a t ≥0, the coefficient of the VT-micro vehicle fuel consumption model, M j,k for a t <0, the coefficient of the VT-micro vehicle fuel consumption model.

[0016] Preferably, the single-vehicle delay minimization objective function is:

[0017]

[0018] Among them, F2 is the single-vehicle delay minimization objective function, T is the vehicle start time, v max is the road speed limit, x T is the position at the end of the vehicle startup phase, and x0 is the initial position of the vehicle startup phase.

[0019] Preferably, the multi-vehicle fuel consumption minimization objective function is:

[0020]

[0021] Among them, F1′ is the objective function for minimizing the fuel consumption of multiple vehicles, n is the total number of vehicles in the queue, T is the vehicle start time, Δt is the preset time interval, and MOE e ′ is the fuel consumption of the vehicle during Δt, MOE e ′ is calculated by the VT-micro vehicle fuel consumption model, e is a natural constant, v i,t is the speed of the ith vehicle at time t, a i,t is the acceleration of the ith vehicle at time t, v i,t The jth power, for a i,t k-th power L j,k for a t ≥0, the coefficient of the VT-micro vehicle fuel consumption model, M j,k for a t <0, the coefficient of the VT-micro vehicle fuel consumption model.

[0022] Preferably, the multi-vehicle delay minimization objective function is:

[0023]

[0024] Among them, F2′ is the multi-vehicle delay minimization objective function, n is the total number of vehicles in the queue, T is the vehicle start time, v max is the road speed limit, v i,t is the speed of the ith vehicle at time t, a i,t is the acceleration of the ith vehicle at time t, x i,T is the position of the i-th vehicle at the end of the vehicle startup phase, x i,0 is the position of the i-th vehicle at the beginning of the vehicle startup phase.

[0025] Preferably, if the vehicle startup scenario is a single vehicle startup scenario, the fuel consumption and delay model of single vehicle startup is:

[0026]

[0027] If the vehicle start scenario is a queue start scenario, the fuel consumption and delay model of the queue start is:

[0028]

[0029] Among them, MinF is the objective function of the fuel consumption and delay model of a single vehicle start, MinF′ is the objective function of the fuel consumption and delay model of queue start, F1 is the objective function for minimizing the fuel consumption of a single vehicle, F2 is the objective function for minimizing the delay of a single vehicle, F1′ is the objective function for minimizing the fuel consumption of multiple vehicles, F2′ is the objective function for minimizing the delay of multiple vehicles, and F 1MAXis the maximum value of the objective function of minimizing the fuel consumption of a single vehicle, F1′ MAX is the maximum value of the objective function of minimizing fuel consumption of multiple vehicles, F 2MAX is the maximum value of the objective function of minimizing the delay of a single vehicle, F2′ MAX is the maximum value of the multi-vehicle delay minimization objective function, α and β are the weight coefficients of the fuel consumption minimization objective function and the delay minimization objective function, respectively, α≥0, β≥0.

[0030] Preferably, if the vehicle startup scenario is a single vehicle startup scenario, constraints are set for the fuel consumption and delay model of the single vehicle startup, including:

[0031] Acceleration constraints:

[0032] a min ≤a t ≤a max ,

[0033] Road speed limit constraints:

[0034] 0≤v t ≤v max , kinematic equation constraints:

[0035]

[0036] v t+1 -v t =a t ×Δt,

[0037] Minimum start distance constraint:

[0038] x T -x0≥s,

[0039] Among them, a min is the minimum acceleration of the vehicle, a t is the acceleration of the vehicle at time t, a max is the maximum acceleration of the vehicle, v t is the speed of the vehicle at time t, v max is the road speed limit, x t is the position of the vehicle at time t, Δt is the preset time interval, x T is the position of the vehicle at the end of the vehicle startup phase, x0 is the initial position of the vehicle during the vehicle startup phase, and s is the minimum startup distance.

[0040] Preferably, if the vehicle start scenario is queue start, constraints are set for the fuel consumption and delay model of the queue start, including:

[0041] Acceleration constraints:

[0042] a min ≤ai,t ≤a max ,

[0043] Road speed limit constraints:

[0044] 0≤v i,t ≤v max , kinematic equation constraints:

[0045]

[0046] v i,t+1 -v i,t =a i,t ×Δt,

[0047] Minimum start distance constraint:

[0048] x i,T -x i,0 ≥s,

[0049] Front vehicle safety distance constraint:

[0050] x i-1,t -x i,t ≥h min

[0051] x i-1,t -x i,t ≥g min ×v i,t ,

[0052] Among them, a min is the minimum acceleration of the vehicle, a i,t is the acceleration of the i-th vehicle at time t, a max is the maximum acceleration of the vehicle, v i,t is the speed of the ith vehicle at time t, v max is the road speed limit, a i,t is the acceleration of the i-th vehicle at time t, x i,t is the position of the i-th vehicle at time t, Δt is the preset time interval, x i,T is the position of the i-th vehicle at the end of the vehicle startup phase, x i,0 is the initial position of the i-th vehicle in the vehicle starting phase, s is the minimum starting distance, h min is the minimum headway, g min is the minimum headway, when g min ×v i,t Less than h min When g min ×v i,t Greater than h min When , the vehicle complies with the minimum headway constraint.

[0053] Preferably, based on the constraints of the fuel consumption and delay model of the current vehicle startup scenario, a sequential least squares quadratic programming algorithm is used to solve the fuel consumption and delay model of the current vehicle startup scenario to obtain the optimal acceleration of the vehicle at different times during the vehicle startup phase.

[0054] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0055] The present invention discloses a joint optimization method for fuel economy and delay in a vehicle startup phase, which considers two startup scenarios: single-vehicle startup and vehicle queuing. If the vehicle startup scenario is single-vehicle startup, a single-vehicle fuel consumption minimization objective function and a single-vehicle delay minimization objective function are constructed according to the road speed limit, vehicle startup time, fuel consumption in the startup phase, the vehicle's instantaneous speed and acceleration, and the initial and end positions of the startup phase; if the vehicle startup scenario is queuing startup, a multi-vehicle fuel consumption minimization objective function and a multi-vehicle delay minimization objective function are constructed according to the road speed limit, the current total number of vehicles and the startup time of each vehicle, fuel consumption in the startup phase, instantaneous speed and acceleration, and the initial and end positions of the startup phase; the two objective functions of the current vehicle startup scenario are normalized to construct a fuel consumption and delay model for the current vehicle startup scenario; and constraint conditions for target optimization are set according to the vehicle startup scenario. On the premise of satisfying constraint conditions such as acceleration, road speed limit, kinematic equation, and minimum startup distance constraint, the optimal acceleration of the vehicle at different times in the vehicle startup phase is solved. It achieves the joint optimization of vehicle fuel economy and start-up delay, which can reduce unnecessary fuel consumption, thereby improving fuel efficiency, reducing vehicle operating costs, enabling vehicles to integrate into traffic flow more smoothly, reducing queuing and waiting time, and improving overall traffic efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0057] Figure 1 It is a flow chart of the steps of the combined optimization method of fuel economy and delay in the vehicle startup phase of the present invention.

[0058] Figure 2 It is a trajectory diagram of different models when the vehicle starting scenario is a single vehicle starting scenario.

[0059] Figure 3 It is a schematic diagram of the optimal acceleration of different models at different times when the vehicle starting scenario is a single vehicle starting scenario.

[0060] Figure 4 It is a trajectory diagram when the vehicle starting scenario is a queue starting scenario.

[0061] Figure 5 It is a schematic diagram of the optimal acceleration of each vehicle at different times when the vehicle starting scenario is a queue starting scenario. DETAILED DESCRIPTION

[0062] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0063] Reference Figure 1 As shown, the first embodiment of the present invention provides a method for jointly optimizing fuel economy and delay during the vehicle startup phase, comprising the following steps:

[0064] Step S1: Divide the vehicle start scenario into two scenarios, namely, a single vehicle start scenario and a vehicle queue start scenario;

[0065] In this embodiment, the vehicle startup phase is defined as a period of time from when the vehicle speed increases from 0 m / s to 30 seconds.

[0066] Step S2: Determine the fuel consumption and delay model, and set the multi-objective optimization function of the vehicle startup phase, including: fuel consumption minimization and delay minimization objective functions;

[0067] In this embodiment, preferably, if the vehicle startup scenario is a single vehicle startup scenario, a single vehicle fuel consumption minimization objective function and a single vehicle delay minimization objective function are constructed according to the road speed limit value, vehicle startup time, fuel consumption during the startup phase, instantaneous speed and acceleration of the vehicle, and the initial position and end position of the startup phase;

[0068] In this embodiment, preferably, the objective function for minimizing the fuel consumption of a single vehicle is:

[0069]

[0070] Among them, F1 is the objective function for minimizing the fuel consumption of a single vehicle, MOE e is the fuel consumption of the vehicle within Δt time, MOE e It is calculated by the VT-micro vehicle fuel consumption model, where T is the vehicle startup time, Δt is the preset time interval, and e is a natural constant. Based on the preset time interval Δt, the vehicle speed v at multiple times t is obtained within the vehicle startup time T. t and acceleration a t , v t is the speed of the vehicle at time t, a t is the acceleration of the vehicle at time t, v t The jth power, for a tkth power, L j,k for a t ≥0, the coefficient of the VT-micro vehicle fuel consumption model, M j,k for a t <0, the coefficient of the VT-micro vehicle fuel consumption model.

[0071] In this embodiment, preferably, the single-vehicle delay minimization objective function is:

[0072]

[0073] Among them, F2 is the single-vehicle delay minimization objective function, T is the vehicle start time, v max is the road speed limit, x T is the position at the end of the vehicle startup phase, and x0 is the initial position of the vehicle startup phase.

[0074] In this embodiment, preferably, if the vehicle startup scenario is queued for startup, a multi-vehicle fuel consumption minimization objective function and a multi-vehicle delay minimization objective function are constructed based on the road speed limit value, the current total number of vehicles and the startup time of each vehicle, the fuel consumption during the startup phase, the instantaneous speed and acceleration, the initial position and the end position of the startup phase.

[0075] In this embodiment, preferably, the multi-vehicle fuel consumption minimization objective function is:

[0076]

[0077] Among them, F1′ is the objective function for minimizing the fuel consumption of multiple vehicles, n is the total number of vehicles in the queue, T is the vehicle start time, Δt is the preset time interval, and MOE e ′ is the fuel consumption of the vehicle during Δt, MOE e ′ is calculated by VT-micro vehicle fuel consumption model, L j,k and M j,k is the coefficient of the VT-micro vehicle fuel consumption model, e is a natural constant, v i,t is the speed of the ith vehicle at time t, a i,t is the acceleration of the ith vehicle at time t.

[0078] In this embodiment, preferably, the multi-vehicle delay minimization objective function is:

[0079]

[0080] Among them, F2′ is the multi-vehicle delay minimization objective function, n is the total number of vehicles in the queue, T is the vehicle start time, v max is the road speed limit, v i,tis the speed of the ith vehicle at time t, a i,t is the acceleration of the ith vehicle at time t, x i,T is the position of the i-th vehicle at the end of the vehicle startup phase, x i,0 is the position of the i-th vehicle at the beginning of the vehicle startup phase.

[0081] L j,k and M j,k is the coefficient of the VT-micro vehicle fuel consumption model. Its value is determined by the positive or negative acceleration and the values ​​of j and k. The specific values ​​are shown in Table 1:

[0082] Table 1

[0083]

[0084] Step S3: performing normalization processing to convert the multi-objective function of step S2 into a single objective function;

[0085] Step S4: setting the constraint conditions for target optimization according to the vehicle start scenario. The single vehicle start scenario includes: acceleration constraint and road speed limit constraint; the queue start scenario includes: acceleration constraint, road speed limit constraint and front vehicle safety distance constraint;

[0086] In this embodiment, preferably, if the vehicle startup scenario is a single vehicle startup scenario, the fuel consumption and delay model of the single vehicle startup is:

[0087]

[0088] Among them, MinF is the objective function of the fuel consumption and delay model of a single vehicle start, F1 is the objective function for minimizing fuel consumption of a single vehicle, F2 is the objective function for minimizing delay of a single vehicle, and F 1MAX is the maximum value of the objective function of minimizing the fuel consumption of a single vehicle, F 2MAX is the maximum value of the single vehicle delay minimization objective function, α and β are the weight coefficients of the fuel consumption minimization objective function and the delay minimization objective function, respectively, α≥0, β≥0.

[0089] The fuel consumption and delay model of a single vehicle start-up sets vehicle acceleration constraints, road speed limit constraints, kinematic equation constraints, and minimum start-up distance constraints, including:

[0090] Acceleration constraints:

[0091] a min ≤a t ≤a max ,

[0092] Road speed limit constraints:

[0093] 0≤v t ≤vmax , kinematic equation constraints:

[0094]

[0095] v t+1 -v t =a t ×Δt,

[0096] Minimum start distance constraint:

[0097] x T -x0≥s,

[0098] Among them, a min is the minimum acceleration of the vehicle, a t is the acceleration of the vehicle at time t, a max is the maximum acceleration of the vehicle, v t is the speed of the vehicle at time t, v max is the road speed limit, x t is the position of the vehicle at time t, Δt is the preset time interval, x T is the position of the vehicle at the end of the vehicle startup phase, x0 is the initial position of the vehicle during the vehicle startup phase, and s is the minimum startup distance.

[0099] In this embodiment, preferably, if the vehicle start scenario is a queue start scenario, the fuel consumption and delay model of the queue start is:

[0100]

[0101] Among them, MinF′ is the objective function of the fuel consumption and delay model of queue start, F1′ is the objective function of minimizing multi-vehicle fuel consumption, F2′ is the objective function of minimizing multi-vehicle delay, and F1′ is the objective function of minimizing multi-vehicle delay. MAX is the maximum value of the objective function of minimizing fuel consumption of multiple vehicles, F2′ MAX is the maximum value of the multi-vehicle delay minimization objective function, α and β are the weight coefficients of the fuel consumption minimization objective function and the delay minimization objective function, respectively, α≥0, β≥0.

[0102] For the fuel consumption and delay model of queue start, set the acceleration constraint, road speed limit constraint, kinematic equation constraint, minimum start distance constraint for each vehicle, and add the front vehicle safety distance constraint, including:

[0103] Acceleration constraints:

[0104] a min ≤a i,t ≤a max ,

[0105] Road speed limit constraints:

[0106] 0≤vi,t ≤v max , kinematic equation constraints:

[0107]

[0108] v i,t+1 -v i,t =a i,t ×Δt, minimum starting distance constraint:

[0109] x i,T -x i,0 ≥s, front vehicle safety distance constraint:

[0110] x i-1,t -x i,t ≥h min

[0111] x i-1,t -x i,t ≥g min ×v i,t ,

[0112] Among them, a min is the minimum acceleration of the vehicle, a i,t is the acceleration of the i-th vehicle at time t, a max is the maximum acceleration of the vehicle, v i,t is the speed of the ith vehicle at time t, v max is the road speed limit, a i,t is the acceleration of the i-th vehicle at time t, x i,t is the position of the i-th vehicle at time t, Δt is the preset time interval, x i,T is the position of the i-th vehicle at the end of the vehicle startup phase, x i,0 is the initial position of the i-th vehicle in the vehicle starting phase, s is the minimum starting distance, h min is the minimum headway, g min is the minimum headway, when g min ×v i,t Less than h min When g min ×v i,t Greater than h min When , the vehicle complies with the minimum headway constraint.

[0113] Step S5: Solve the model of step S2 according to the constraint conditions and draw a vehicle trajectory diagram.

[0114] In this embodiment, preferably, based on the constraints of the fuel consumption and delay model of the current vehicle startup scenario, the fuel consumption and delay model of the current vehicle startup scenario is solved using a sequential least squares quadratic programming algorithm to obtain the optimal acceleration of the vehicle at different times during the vehicle startup phase. Using a sequential least squares quadratic programming algorithm to solve the fuel consumption and delay model can make full use of its advantages in nonlinear and multi-constrained optimization, and can effectively converge to the optimal solution, thereby obtaining the optimal acceleration of the vehicle at different times during the vehicle startup phase.

[0115] In this embodiment, the vehicle startup scene is selected as a single vehicle startup scene, and the setting parameters are shown in Table 2:

[0116] Table 2

[0117]

[0118] The fuel consumption and delay model weight coefficients α=0, β=1 are used as a single fuel consumption optimization model, and the fuel consumption and delay model weight coefficients α=1, β=0 are used as a single delay optimization model. The results are compared and the vehicle trajectory curve is drawn according to the results, such as Figure 2 , 3 As shown, Figure 2 Trajectory diagrams of different models when the vehicle startup scenario is a single vehicle startup scenario. Figure 3 Schematic diagram of the optimal acceleration of different models at different times when the vehicle startup scenario is a single vehicle startup scenario.

[0119] The numerical comparison of different optimization models is shown in Table 3:

[0120] Table 3

[0121]

[0122] From the results, it can be analyzed that the fuel consumption and delay model proposed in the present invention achieves the best balance between total delay and fuel consumption, showing a lower total delay time and fuel consumption per 100 kilometers. Compared with the delay optimization model and the fuel consumption optimization model, this model has better comprehensive performance and is suitable for scenarios with high requirements on fuel economy and traffic delays, and has higher application value.

[0123] In this embodiment, the vehicle start scenario is selected as the queue start scenario, and the setting parameters are shown in Table 4:

[0124] Table 4

[0125]

[0126] Draw the vehicle trajectory curve as Figure 4 As shown, Figure 4 This is the trajectory diagram when the vehicle startup scenario is a queue startup scenario. Figure 5 As shown, Figure 5 It is a schematic diagram of the optimal acceleration of each vehicle at different times when the vehicle starting scenario is a queue starting scenario.

[0127] The present invention determines the optimal balance between vehicle fuel economy and delay under the premise of satisfying constraints such as acceleration, road speed limit, kinematic equation, minimum starting distance constraint, etc., and obtains the optimal acceleration of the vehicle at different times in the vehicle starting phase in the vehicle starting scenario, thereby achieving joint optimization of vehicle fuel economy and starting delay, which can reduce unnecessary fuel consumption, thereby improving fuel efficiency, reducing vehicle operating costs, enabling vehicles to integrate into traffic flow more smoothly, reducing queuing and waiting time, and improving overall traffic efficiency.

[0128] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0129] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0130] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0131] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0132] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A joint optimization method for fuel economy and delay in the vehicle startup phase, characterized in that: The following steps are involved: Step S1: Divide the vehicle starting scenario into two scenarios, namely, a single vehicle starting scenario and a vehicle queue starting scenario; Step S2: Determine the fuel consumption and delay model, and set the multi-objective optimization function of the vehicle startup phase, including: fuel consumption minimization and delay minimization objective functions; Step S3: Perform normalization processing to convert the multi-objective function of step S2 into a single objective function; Step S4: setting the constraint conditions for target optimization according to the vehicle start scenario. The single vehicle start scenario includes: acceleration constraint and road speed limit constraint; the queue start scenario includes: acceleration constraint, road speed limit constraint and front vehicle safety distance constraint; Step S5: Solve the model of step S2 according to the constraint conditions and draw a vehicle trajectory diagram.

2. The method for joint optimization of fuel economy and delay in the vehicle startup phase according to claim 1, characterized in that: If the vehicle startup scenario is a single vehicle startup scenario, the single vehicle fuel consumption minimization objective function and the single vehicle delay minimization objective function are constructed based on the road speed limit, vehicle startup time, fuel consumption during the startup phase, vehicle instantaneous speed and acceleration, and the initial and end positions of the startup phase; If the vehicle startup scenario is queued, the multi-vehicle fuel consumption minimization objective function and the multi-vehicle delay minimization objective function are constructed based on the road speed limit, the current total number of vehicles, the startup time of each vehicle, the fuel consumption during the startup phase, the instantaneous speed and acceleration, the initial position and the end position of the startup phase.

3. The method for joint optimization of fuel economy and delay in the vehicle startup phase according to claim 2, characterized in that: The objective function for minimizing the fuel consumption of a single vehicle is: Among them, F1 is the objective function for minimizing the fuel consumption of a single vehicle, MOE e is the fuel consumption of the vehicle within Δt time, MOE e It is calculated by the VT-micro vehicle fuel consumption model, where T is the vehicle startup time, Δt is the preset time interval, e is a natural constant, and v t is the speed of the vehicle at time t, a t is the acceleration of the vehicle at time t, v t The jth power, for a t kth power, L j,k for a t ≥0, the coefficient of the VT-micro vehicle fuel consumption model, M j,k for a t <0, the coefficient of the VT-micro vehicle fuel consumption model.

4. The method for joint optimization of fuel economy and delay in the vehicle startup phase according to claim 2, characterized in that: The objective function for minimizing the delay of a single vehicle is: Among them, F2 is the single-vehicle delay minimization objective function, T is the vehicle start time, v max is the road speed limit, x T is the position at the end of the vehicle startup phase, and x0 is the initial position of the vehicle startup phase.

5. The method for joint optimization of fuel economy and delay in the vehicle startup phase according to claim 2, characterized in that: The objective function for minimizing the fuel consumption of multiple vehicles is: Among them, F1′ is the objective function for minimizing the fuel consumption of multiple vehicles, n is the total number of vehicles in the queue, T is the vehicle start time, Δt is the preset time interval, and MOE e ′ is the fuel consumption of the vehicle during Δt, MOE e ′ is calculated by the VT-micro vehicle fuel consumption model, e is a natural constant, v i,t is the speed of the i-th vehicle at time t, a i,t is the acceleration of the ith vehicle at time t, v i,t The jth power, for a i,t k-th power L j,k for a t ≥0, the coefficient of the VT-micro vehicle fuel consumption model, M j,k for a t <0, the coefficient of the VT-micro vehicle fuel consumption model.

6. The method for joint optimization of fuel economy and delay in the vehicle startup phase according to claim 2, characterized in that: The multi-vehicle delay minimization objective function is: Among them, F2′ is the multi-vehicle delay minimization objective function, n is the total number of vehicles in the queue, T is the vehicle start time, v max is the road speed limit, v i,t is the speed of the ith vehicle at time t, a i,t is the acceleration of the ith vehicle at time t, x i,T is the position of the i-th vehicle at the end of the vehicle startup phase, x i,0 is the position of the i-th vehicle at the beginning of the vehicle startup phase.

7. The method for joint optimization of fuel economy and delay in vehicle startup phase according to claim 2, characterized in that: If the vehicle start scenario is a single vehicle start scenario, the fuel consumption and delay model of single vehicle start is: If the vehicle start scenario is a queue start scenario, the fuel consumption and delay model of the queue start is: Among them, MinF is the objective function of the fuel consumption and delay model of a single vehicle start, MinF′ is the objective function of the fuel consumption and delay model of queue start, F1 is the objective function for minimizing the fuel consumption of a single vehicle, F2 is the objective function for minimizing the delay of a single vehicle, F1′ is the objective function for minimizing the fuel consumption of multiple vehicles, F2′ is the objective function for minimizing the delay of multiple vehicles, and F 1MAX is the maximum value of the objective function of minimizing the fuel consumption of a single vehicle, F1′ MAX is the maximum value of the objective function of minimizing fuel consumption of multiple vehicles, F 2MAX is the maximum value of the objective function of minimizing the delay of a single vehicle, F2′ MAX is the maximum value of the multi-vehicle delay minimization objective function, α and β are the weight coefficients of the fuel consumption minimization objective function and the delay minimization objective function, respectively, α≥0, β≥0.

8. The method for joint optimization of fuel economy and delay in the vehicle startup phase according to claim 7, characterized in that: If the vehicle startup scenario is a single vehicle startup scenario, set constraints on the fuel consumption and delay model of single vehicle startup, including: Acceleration constraints: a min ≤a t ≤a max , Road speed limit constraints: 0≤v t ≤v max , Kinematic equation constraints: in t+1 -v t =a t ×Δt, Minimum start distance constraint: x T -x0≥s, Among them, a min is the minimum acceleration of the vehicle, a t is the acceleration of the vehicle at time t, a max is the maximum acceleration of the vehicle, v t is the speed of the vehicle at time t, v max is the road speed limit, x t is the position of the vehicle at time t, Δt is the preset time interval, x T is the position of the vehicle at the end of the vehicle startup phase, x0 is the initial position of the vehicle during the vehicle startup phase, and s is the minimum startup distance.

9. The method for joint optimization of fuel economy and delay in vehicle startup phase according to claim 1, characterized in that: If the vehicle start scenario is queue start, set constraints on the fuel consumption and delay model of the queue start, including: Acceleration constraints: a min ≤a i，t ≤a max , Road speed limit constraints: 0≤v i，t ≤v max , Kinematic equation constraints: in i，t+1 -v i，t =a i，t ×Δt, Minimum start distance constraint: x i,T -x i，0 ≥s, Front vehicle safety distance constraint: x i-1，t -x i,t ≥h min x i-1，t -x i,t ≥g min ×v i,t , Among them, a min is the minimum acceleration of the vehicle, a i，t is the acceleration of the i-th vehicle at time t, a max is the maximum acceleration of the vehicle, v i，t is the speed of the ith vehicle at time t, v max is the road speed limit, a i，t is the acceleration of the i-th vehicle at time t, x i，t is the position of the i-th vehicle at time t, Δt is the preset time interval, x i,T is the position of the i-th vehicle at the end of the vehicle startup phase, x i，0 is the initial position of the i-th vehicle in the vehicle starting phase, s is the minimum starting distance, h min is the minimum headway, g min is the minimum headway, when g min ×v i，t Less than h min When g min ×v i，t Greater than h min When , the vehicle complies with the minimum headway constraint.

10. The method for joint optimization of fuel economy and delay in vehicle startup phase according to claim 1, characterized in that: Based on the constraints of the fuel consumption and delay model of the current vehicle startup scenario, the sequential least squares quadratic programming algorithm is used to solve the fuel consumption and delay model of the current vehicle startup scenario, and the optimal acceleration of the vehicle at different times during the vehicle startup phase is obtained.

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