CN104680788A - Ecological impedance calculating method for traffic path selection - Google Patents

Abstract

The invention discloses an ecological impedance calculating method for traffic path selection. The method comprises the following steps: constructing a road section ecological impedance model; constructing a node ecological impedance model; calculating an oil consumption discharging factor of road section ecological impedance and an oil consumption discharging factor of node ecological impedance according to the road section ecological impedance model and the node ecological impedance model, and selecting a traffic path with the minimum sum of the oil consumption discharging factor of the road section ecological impedance and the oil consumption discharging factor of the node ecological impedance. According to the ecological impedance calculating method, a method instruction can be provided for real-time quantitative evaluation of oil consumption discharging, so that a traffic strategy can be quickly evaluated, and a theoretical foundation can be provided for control and reduction of tail gas discharging of a locomotive.

Description

A kind of eco-resi stance computing method selected for traffic route

Technical field

The present invention relates to the eco-resi stance computing method in field of traffic.More specifically, a kind of eco-resi stance computing method selected for traffic route are related to.

Background technology

At present for the research of link proportion:

In many traffic impedance factors, time factor is topmost.For single transportation network, traveler, when carrying out routing, is all generally be target with shortest time.Some transportation network, the running time on section is directly proportional to distance, has nothing to do, as urban rail transit net with the flow on section.Some transportation network, as network of highways, urban road network, the running time on section is not necessarily directly proportional to distance, and relevant to the magnitude of traffic flow on section, now just selects the time as impedance.This kind of running time is comparatively complicated with the relation of distance, flow, and this relation can being expressed as of broad sense:

C _a＝f({V})

Namely the expense on section is not only the function of the flow in section own, and is the function of flow V on whole road network.This general formula is more common at urban road on the net, because the existence of crossing, the flow on different sections of highway can influence each other.For network of highways, because section is long, this relation can simplify further, because the most of the time spends on section instead of on crossing, at this moment formula can be written as:

C _a＝f({V _a})

Namely the expense in section is only relevant to the flow in this section and characteristic thereof, and this supposes the exploitation of foundation and demarcation and the traffic flow apportion model simplified section function.

For the research of the road running function of time, existingly carry out regretional analysis by measured data, also have and to carry out theoretical research.What be wherein widely used is the function developed by Bureau of Public Roads Bureau of Public Road, BPR, and be called as BPR function, form is:

$t_a=t_0[1+\mathrm{\α}{\left(\frac{q_a}{c_a}\right)}^{\mathrm{\β}}]$

In formula, t _afor the impedance on a of section; t ₀be zero flow impedance, namely on section flow for 0 time vehicle travel required for time; q _afor the volume of traffic on a of section; c _afor the practical tonnage capacity of section a, namely in the unit interval, section is actual in vehicle number; α, β are retardation factor, and in Bureau of Public Roads traffic flow allocator, the value of α, β parameter is respectively α=0.15, β=4, and the value of α, β parameter also can be tried to achieve by real data regretional analysis.

Prior art is for the research of node impedance:

Node impedance refers to that vehicle mainly refers to the impedance in crossing at transportation network Nodes.Crossing impedance is relevant with the factor such as form, the timing of whistle control system, the handling capacity of crossing of crossing.In the actual travel time of urban traffic network, except link travel time, intersection delay occupies larger proportion, and particularly in rush-hour, when the crowded blockage ratio of crossing is more serious, the delay of crossing may exceed link travel time.

In traffic engineering, have excessive quantifier elimination to the delay of signalized intersections, direct object is the timing for signalized crossing, and the design of some control, line traffic control and face Ore-controlling Role and crossing handling capacity calculate carries out.The impedance of Nodes can be divided into two classes:

(1) regardless of flowing to class: the impedance respectively flowed at certain node is substantially identical, or significantly difference is not flowed to dividing of regularity.To the relatively good process of this kind of problem, same unified value represents the delay of vehicle in node i.

(2) divide and flow to class: various flows to impedance different, and generally obey certain rule.Like this urban road network is exactly, and vehicle generally has three flow directions in the crossing of urban road: keep straight on, turn left, turn right, the time difference incured loss through delay is obvious, and generally obeys rule: right-hand rotation < craspedodrome < turns left.In fact, vehicle also also exists same delay rule at the Nodes of intercity network of highways.But the section of network of highways is long, vehicle is very little relative to the running time on section in the delay of Nodes, can be approximated to be 0, so just it can be belonged to above-mentioned " regardless of flowing to class " and treat.But urban road network crossing is intensive, the section between Adjacent Intersections often only has hundreds of rice, and the vehicle delay time at stop that some flows in crossing close to even exceeding the running time on section, therefore can not ignore, and the flow direction must be divided to calculate.

Point to flow to when calculating, general represent that vehicle from node i is in the delay of crossing j, it can be incured loss through delay formula with Webster and represent.

The people such as the F.V.Webster of TRRL research institute of Britain Transport and Road Research Laboratory in 1958 are theoretical according to waiting line theory, propose the model that calculates intersection delay.Mainly comprise two parts in this model, the normal phase place that a part is vehicle arriving rate to be produced when being fixing average is incured loss through delay and uniform delay, the additional delay produced when another part is vehicle arriving rate random fluctuation.Its concrete form is:

$t_p=\frac{T{(1-\mathrm{\&lambda;})}^2}{2(1-\mathrm{\&lambda;X})}+\frac{X^2}{2Q(1-X)}-0.65{\left(\frac{T}{Q^1}\right)}^{\frac{1}{3}}{X}^{(2+5\mathrm{\&lambda;})}$

In formula, T is signal period length; λ is entrance driveway effective green time and signal period length ratio, i.e. split; Q is the magnitude of traffic flow of entrance driveway; X is saturation degree, and X=Q/S, S are entrance driveway handling capacity.

Above-mentioned formula be Webster on the basis of Monter-Carlo analog result, correct the delay formula form that the traffic engineers that gone out by waiting line theory theory deduction are originally conventional.

Prior art is for the research of ecological route Eco-routing navigational system:

Nowadays, in order to allow the automobile driven accomplish more fuel-efficient, more energy saving standard, automobile production manufacturer resorts to every conceivable means, and the therefore design of automobile, fuel-saving technique develop rapidly also with rapid changepl. never-ending changes and improvementsly.But, for the imperfect driver of those senses of direction, if the road of destination cannot be found, economize petrol car even if drive, also in detouring, unnecessarily can only increase oil consumption.A kind of can for driver provide the vehicle mounted guidance instrument system of fuel-efficient drive route this be just can play a role.In minimizing traffic congestion, pressure and waste of fuel, though the energy-saving potential of said system is not yet fully expanded, possesses the advantage reaching win-win situation.For example, if automobile is avoided blocking section, select the route that fuel efficiency is the highest, driver can reach the destination sooner and reduce anxiety.Fuel-efficient route provides the minimum route of oil consumption.

Ecological route (Eco-routing), for multiple technologies are in conjunction with achievement, comprise utilization action honeycomb technology, geo-location and computer system in use for vehicle and jointly finds out alternative route.Especially, when driver utilizes Global Positioning System (GPS) (GPS) system programming route, traffic congestion must be avoided and find more short-circuit line or entirety to possess the modes such as the route of optimal fuel economy.Another similar approach and network cruise control technology (Connected Cruise Control Technology), drive from traffic control center receive the speed of a motor vehicle suggestion, vehicle also can sharing information with avoid accident section or coordinate the speed of a motor vehicle to reduce blocking.

This ecological route navigational system can calculate the acceleration and deceleration of each road according to the running data accumulated before this, utilize the burnup database that server admin makes according to each time period traffic congestion change, while combining the traffic congestion time of going to destination, calculate fuel-efficient route.In addition, for the object for calculating more high-precision fuel-efficient route accumulation basic data from now on, the work of the actual burnup data of automobile is used to start since then.At present, this intelligent guidance system assembles in a lot of vehicle.

Ecological drive target under, tradition incur loss through delay index and oil consumption discharge between relation there is very large uncertainty, so traditional delay index can not directly as the substitute variable of eco-resi stance.

For link proportion, traditional impedance function only establishes the relation between road section traffic volume load and link travel time, fail to reflect the impact of the driving behavior of vehicle on oil consumption exhaust emissions further, also just oil consumption exhaust emissions can not be set up with road section traffic volume feature and effectively be connected.

For node impedance, traditional impedance function only establishes the relation between crossing load and intersection delay, fail the further impact of reflection on oil consumption exhaust emissions, oil consumption exhaust emissions can not be set up with the traffic characteristic of crossing and effectively be connected.

For existing ecological route navigational system, the method being calculated fuel-efficient route by the running data accumulated before this cannot embody the driving behavior of section and crossing and the operational factor of vehicle, also reflection transport need that just can not be real-time, specifically also just can not set up the relational model between the real-time magnitude of traffic flow and actual burnup emissions data.

Therefore, need to provide a kind of eco-resi stance computing method selected for traffic route.

Summary of the invention

The object of the present invention is to provide a kind of eco-resi stance computing method selected for traffic route.

For achieving the above object, the present invention adopts following technical proposals:

For the eco-resi stance computing method that traffic route is selected, the method comprises the steps:

S1, set up section eco-resi stance model, model formation is:

$y={\mathrm{\&alpha;}}_1\&CenterDot;{v_a}^{{\mathrm{\&beta;}}_1}$

In formula, v _afor the average velocity on a of section, unit km/h; Y is oil consumption emission factor, and unit is ml/km or g/km; α ₁, β ₁be oil consumption emission factor velocity fitting coefficient;

S2, set up node eco-resi stance model, model formation is:

y'＝α ₂t _w+β ₂

In formula, t _wfor intersection delay, unit is s; Y ' is oil consumption emission factor delay correction factor; α ₂, β ₂be oil consumption emission factor and incur loss through delay fitting coefficient;

S3, according to section eco-resi stance model and node eco-resi stance model, calculate the oil consumption emission factor of section eco-resi stance and the oil consumption emission factor of node eco-resi stance, select the traffic route that the oil consumption emission factor sum of the oil consumption emission factor of section eco-resi stance and node eco-resi stance is minimum.

Preferably, step S1 comprises following sub-step further:

S1.1, the average velocity v calculated on a of section _a;

S1.2, set up section oil consumption emission factor speed correction model based on vehicle specific power VSP, as section eco-resi stance model.

Preferably, step S2 comprises following sub-step further:

S2.1, calculating intersection delay t _w;

The average stop frequency of S2.2, calculating signal period each car interior;

S2.3, set up crossing oil consumption emission factor incur loss through delay correction model, as node eco-resi stance model.

Preferably, the average velocity v on a of section is calculated in step S1.1 _aformula be:

$v_a=L_a/t_0[1+\mathrm{\&alpha;}{\left(\frac{q_a}{c_a}\right)}^{\mathrm{\&beta;}}]$

In formula, L _afor the length of section a; t _afor the impedance of section a; t ₀it is zero flow impedance; q _afor the volume of traffic of section a; c _afor the practical tonnage capacity of section a; α, β are retardation factor.

Preferably, step S1.2 comprises sub-step further:

S1.2.1, calculating Light-duty Vehicle are by the instantaneous VSP value of second, and formula is as follows:

VSP＝v·(1.1a`+0.132)+0.000302·v ³

In formula, v be Light-duty Vehicle by speed second, unit is m/s; A` be Light-duty Vehicle by acceleration second, unit is m/s ²;

S1.2.2, be that step-length carries out cluster to the instantaneous VSP value by second with 1kW/t, the instantaneous VSP value by second is divided into interval unit VSPBin according to interval division principle, and formula is as follows:

$\mathrm{VSPBin}=i,\&ForAll;:\mathrm{VSP}\&Element;[i,i+1)$

In formula, the span of i is the integer between [-20,20];

S1.2.3, be time granularity with 60s, divide short stroke, and calculate the average velocity of each short stroke by averaging to each travel speed of continuous 60s;

S1.2.4, be that step-length carries out interval division to average velocity with 2km/h, judge the speed interval at average velocity place, the data identical to the left end point value Int Speed of all speed intervals carry out cluster, add up total number of the respective number of each interval unit VSP Bin corresponding to the left end point value Int speed of each speed interval and the instantaneous VSP value by second, the distributive law of each VSP Bin under calculating each Int speed, formula is as follows:

$R_{i,k}=\frac{N_{i,k}}{N_k}$

In formula, k is the value of the left end point value Int speed of speed interval; I is the value of interval unit VSP Bin, and span is the integer between [-20,20]; R _{i, k}the distributive law of i-th interval unit VSP Bin when be the left end point value Int Speed of speed interval being k; N _{i, k}by the sum of the instantaneous VSP value of second when be Int Speed being k; N _kwhen be Int Speed being k, interval unit VSP Bin is the instantaneous VSP value number by second of i;

S1.2.5, calculate oil consumption emission factor corresponding to each speed interval, formula is as follows:

${\mathrm{EF}}_{j,k}=\frac{{\mathrm{\&Sigma;}}_i{\mathrm{er}}_{i,j}\&times;R_{i,k}}{k+1}$

In formula, EF _j,kthe emission factor of the jth kind oil consumption factor or pollutant when left end point value Int Speed for speed interval is k, pollutant comprises CO, NO _xand HC; Er _i,jit is the emission index of jth kind rate of fuel consumption or pollutant in i-th interval unit VSP Bin; R _i,kthe distributive law of i-th interval unit VSP Bin when be the left end point value Int Speed of speed interval being k;

S1.2.6, set up section oil consumption emission factor speed correction model based on VSP, as section eco-resi stance model, formula is as follows:

$y={\mathrm{\&alpha;}}_1\&CenterDot;{v_a}^{{\mathrm{\&beta;}}_1}$

In formula, v _athe average velocity on a of section, unit km/h; Y is oil consumption emission factor, and unit is ml/km or g/km; α ₁, β ₁be oil consumption emission factor velocity fitting coefficient, α ₁, β ₁according to each oil consumption factor of correspondence under each speed interval or the emission factor EF of pollutant _j,kwith the negative power function value of the graph of a relation matching of average velocity.

Preferably, intersection delay t is calculated in step S2.1 _pformula be:

$t_p=\frac{T{(1-\mathrm{\&lambda;})}^2}{2(1-\mathrm{\&lambda;X})}+\frac{X^2}{2Q(1-X)}-0.65{\left(\frac{T}{Q^1}\right)}^{\frac{1}{3}}{X}^{(2+5\mathrm{\&lambda;})}$

In formula, T is signal period length; λ is entrance driveway effective green time and signal period length ratio; Q is the magnitude of traffic flow of entrance driveway; X is saturation degree, and X=Q/S, S are entrance driveway handling capacity.

Preferably, step S2.2 comprises following sub-step further:

S2.2.1, calculate the average stop frequency h of w phase place vehicle _w, formula is as follows:

$h_w=\underset{r}{\mathrm{\&Sigma;}}0.9\frac{C-C_{\mathrm{ew}}}{1-y_{\mathrm{wr}}}$

In formula, C _ewfor the effective green time of w phase, y _wrfor the throughput ratio of r entrance driveway of w phase;

The average stop frequency of S2.2.2, calculating signal period each car interior, formula is as follows:

$H=\underset{w=1}{\mathrm{\&Sigma;}}{h}_w{q}_w/\underset{w=1}{\mathrm{\&Sigma;}}{q}_w$

In formula, q _wfor the flow of w phase.

Preferably, step S2.3 comprises following sub-step further:

S2.3.1, the calculating basic emission factor EF in crossing _b, formula is as follows:

${\mathrm{EF}}_b=({\mathrm{\&Sigma;}}_{-15}^{15}{\mathrm{ER}}_i\&times;D_i)\&times;\frac{T_b}{L_b}\&times;1000$

In formula, ER _ibe the oil consumption emission index in i-th interval unit VSPBin, unit is g/s; D _iit is the Annual distribution ratio in i-th VSP interval; L _bfor motor vehicle is in the total kilometres in this section, unit is m; T _bfor motor vehicle is at the overall travel time in this section, unit is s;

S2.3.2, calculate average fuel consumption emission factor EF corresponding to each intersection delay _m, formula is as follows:

${\mathrm{EF}}_m=({\mathrm{\&Sigma;}}_{-15}^{15}{\mathrm{ER}}_i\&times;D_i)\&times;\frac{T_m}{L_m}\&times;1000$

In formula, ER _ibe the rate of fuel consumption emission index of i-th interval unit VSPBin, unit is g/s; D _ifor incuring loss through delay the Annual distribution ratio for i-th interval unit VSPBin during m; L _mfor incuring loss through delay the crossing size for m, unit is m; T _mfor incuring loss through delay the overall travel time of the intersection vehicles for m, unit is s;

The delay correction factor SCF of S2.3.3, the oil consumption calculating each intersection delay and emission factor _m, formula is as follows:

SCF _m＝EF _m/EF _b；

S2.3.4, set up crossing oil consumption emission factor incur loss through delay correction model, as node eco-resi stance model, formula is as follows:

y'＝α ₂t _w+β ₂

In formula, t _wfor intersection delay, unit is s; Y ' is that oil consumption emission factor incurs loss through delay correction factor; α ₂, β ₂be oil consumption emission factor and incur loss through delay fitting coefficient, α ₂, β ₂oil consumption emission factor according to different stop frequencies corresponding to each intersection delay incurs loss through delay correction factor SCF _mthe linear function value of scatter diagram matching.

Beneficial effect of the present invention is as follows:

Technical scheme of the present invention is on the basis based on Conventional impedance function, under a large amount of collection analysis vehicle working condition data prerequisite, analyze the distribution character of VSP, establish the relation between VSP distribution and delay, recycle existing Delay Model and set up the delay correction model discharging measuring and calculating for vehicle in section and crossing's oil consumption.The parameter of the traffic behavior parameter and crossing that are easy to the real-time vehicle obtained is discharged with motor vehicle fuel consumption and associates, set up the model of the eco-resi stance of section and node, evaluate supplying method for the real-time quantization effectively realizing oil consumption discharge to instruct, and then evaluate Transportation Strategies fast and effectively, for farthest controlling and reducing motor vehicle fuel consumption and exhaust emissions provides theoretical foundation.

Accompanying drawing explanation

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in further detail.

Fig. 1 illustrates the eco-resi stance computing method process flow diagram selected for traffic route.

Fig. 2 illustrates section eco-resi stance model construction schematic diagram.

Fig. 3 illustrates the oil consumption emission factor speed correction model schematic diagram based on VSP.

Fig. 4 illustrates node eco-resi stance model construction schematic diagram.

Fig. 5 illustrates through street oil consumption factor speed correction model schematic diagram.

Fig. 6 illustrates through street CO emission factor speed correction model schematic diagram.

Fig. 7 illustrates through street NO _xemission factor speed correction model schematic diagram.

Fig. 8 illustrates through street HC emission factor speed correction model schematic diagram.

Embodiment

In order to be illustrated more clearly in the present invention, below in conjunction with preferred embodiments and drawings, the present invention is described further.Parts similar in accompanying drawing represent with identical Reference numeral.It will be appreciated by those skilled in the art that specifically described content is illustrative and nonrestrictive, should not limit the scope of the invention with this below.

The eco-resi stance computing method selected for traffic route that the present embodiment provides, comprise the steps:

Step1, set up section eco-resi stance model;

Model construction thinking is: apply the BPR function developed by Bureau of Public Roads and set up relation between link proportion and the volume of traffic, and calculate the impedance on a of section.Recycle based on the oil consumption emission factor speed correction model of VSP set up driving trace and average bicycle discharge between relation.Last according to the average velocity v on a of section _a, impedance t _awith the length L of section a _athe relational expression existed finally sets up the relational model between " the average bicycle discharge " of point road type and link flow.

Step Step1 specifically comprises following sub-step:

Step1.1, the average velocity v calculated on a of section _a;

First calculate link proportion, what computing method were applied is the function developed by Bureau of Public Roads Bureau of Public Road, BPR, and be called as BPR function, formula is:

$t_a=t_0[1+\mathrm{\&alpha;}{\left(\frac{q_a}{c_a}\right)}^{\mathrm{\&beta;}}]$

In formula, t _afor the impedance on a of section; t ₀be zero flow impedance, namely on section flow for 0 time vehicle travel required for time; q _afor the volume of traffic on a of section; c _afor the practical tonnage capacity of section a, namely in the unit interval, section is actual in vehicle number; α, β are retardation factor, and in Bureau of Public Roads traffic flow allocator, the value of α, β parameter is respectively α=0.15, β=4, and the value of α, β parameter also can be tried to achieve by real data regretional analysis.

Due to the average velocity v on a of section _a, impedance t _awith the length L of section a _ameet following relation:

v _a＝L _a/t _a

Then calculate the average velocity v on a of section _aformula as follows:

$v_a=L_a/t_0[1+\mathrm{\&alpha;}{\left(\frac{q_a}{c_a}\right)}^{\mathrm{\&beta;}}]$

Step1.2, set up based on vehicle specific power Vehicle Specific Power, be called for short the section oil consumption emission factor speed correction model of VSP, as section eco-resi stance model;

Set up and first need to collect a large amount of data based on driving trace emission factor speed correction model, the emission index data mainly comprising motor-driven vehicle going track data and distribute based on VSP Bin.Wherein the collection of motor-driven vehicle going track data is then specifically by installing the gps data that the equipment such as GPS collect Floating Car on testing vehicle.Due to the relational model between " the average bicycle discharge " of point road type and link flow will be set up, a car can be selected herein at the driving trace of each grade road of Beijing road network within some day, then carry out integration for the Floating Car raw data collected and process obtains floating car data storehouse.Based on the emission index of VSP Bin distribution, the technology of the selected testing vehicle self of rate of fuel consumption data needs combination and service condition, for Light-Duty Gasoline Vehicle, for respectively discharging pollutants under state III standard, comprise average emission rate and the mean-fuelconsumption rate of CO, NOx, HC.

Step Step1.2 specifically comprises following sub-step:

Step1.2.1, computing machine motor-car are by the instantaneous VSP value of second:

Finding that utilize vehicle specific power VSP to distribute portraying traffic behavior is Research Requirements up-to-date at present, is also the research and apply direction of following oil consumption discharge model.VSP refers to the engine often power that exports of mobile one ton of quality, and quality pack is wherein containing motor vehicle deadweight, and unit is kW/t or W/kg.As follows by the computing formula of the instantaneous VSP value of second for calculating Light-duty Vehicle:

VSP＝v·(1.1a'+0.132)+0.000302·v ³

In formula, v be Light-duty Vehicle by speed second, unit is m/s; A ' is Light-duty Vehicle by acceleration second, and unit is m/s ².

Step1.2.2, cluster is carried out to the instantaneous VSP value by second, the instantaneous VSP value by second is divided according to interval division principle:

The people such as Fery are in order to describe the correlativity of VSP variable and motor vehicle fuel consumption more clearly, the method of VSP cluster is proposed in 2002, different interval unit is divided into according to certain interval by VSP value, this interval unit is defined as Bin, and the mean-fuelconsumption rate calculated under each interval unit B in and emission index are as the basic data of model.Wherein, VSP value divides the accuracy of the direct impact analysis result of gap size.

By to more than 400,000, Beijing Floating Car by number of seconds according to the research of being correlated with, the present embodiment determines to take 1kW/t as the division methods at interval carries out cluster and oil consumption emission index polymerization to VSP.Find by analyzing, the VSP value of 98.9% concentrates in the VSP interval of-20kW/t ~ 20kW/t, and the ratio that the sample size that VSP absolute value is greater than 20kW/t then accounts for total sample size is no more than 2%.Therefore, between the interval study area as emphasis of VSP that have chosen-20kW/t to 20kW/t herein, namely n is the integer between [-20,20].

Be that step-length carries out clustering processing to VSP value with 1kW/t, VSP value divided according to interval division principle, formula is as follows:

$\mathrm{VSPBin}=i,\&ForAll;:\mathrm{VSP}\&Element;[i,i+1)$

In formula, i is the integer between [-20,20].

Step1.2.3, be time granularity with 60s, divide short stroke, and calculate the average velocity of each short stroke by averaging to each travel speed of continuous 60s.

Step1.2.4, interval division is carried out to average velocity.Under the prerequisite taking into account degree of accuracy and sample data amount, be that step-length carries out interval division ([0,2], [2,4] to average velocity with 2km/h ...).According to the method, judge the speed interval at average velocity place, and in floating car data storehouse data basis on increase to the left end point value Int Speed of each speed interval.

The data identical to the left end point value Int Speed of all speed intervals carry out cluster, add up 41 interval VSP Bin numbers separately by the instantaneous VSP value of second corresponding to each Int speed and total number of VSP value, thus the distributive law of each VSP Bin under calculating each Int speed, formula is as follows:

$R_{i,k}=\frac{N_{i,k}}{N_k}$

In formula, k is the value of Int speed, is the left end point value of each speed interval; I is the value of VSP Bin, and span is the integer between [-20,20]; R _{i, k}the distributive law of i-th VSP Bin when be Int Speed being k; N _{i, k}the sum of VSP value when be Int Speed being k; N _kwhen be Int Speed being k, VSP Bin is the VSP number of i.

According to the computing formula of VSP distributive law, the distributive law of VSP under different road type, friction speed interval can be calculated.

Step1.2.5, calculate oil consumption emission factor corresponding to each speed interval:

The VSP distributive law calculated is multiplied with the oil consumption emission index of each pollutant of selected vehicle and is sued for peace respectively, then removes the average velocity in corresponding speed interval, the oil consumption emission factor of each pollutant corresponding under can obtaining each speed interval, formula is as follows:

${\mathrm{EF}}_{j,k}=\frac{{\mathrm{\&Sigma;}}_i{\mathrm{er}}_{i,j}\&times;R_{i,k}}{k+1}$

In formula, k is the value of Int speed, is the left end point value of each speed interval, EF _j,kthe emission factor of the jth kind oil consumption factor or pollutant when be Int Speed being k, pollutant comprises CO, NO _xand HC; Er _i,jthe emission index of i-th VSP Bin jth kind rate of fuel consumption or pollutant, er _i,jbe the technology in conjunction with institute's testing vehicle self and service condition, what choose here is Light-Duty Gasoline Vehicle discharge model, at the substandard mean-fuelconsumption rate of state III and respectively discharge pollutants (CO, NO _x, HC) emission index; R _i,kthe distributive law of i-th VSP Bin when be Int Speed being k.

Step1.2.6, set up section oil consumption emission factor speed correction model based on VSP, as section eco-resi stance model:

According on each grade road of formulae discovery in different average velocity intervals emission factor, thus set up the oil consumption emission factor of each speed interval on each grade road.

Following Main Analysis through street oil consumption emission factor speed correction model.Graph of a relation between the oil consumption emission factor of each speed interval of through street is as shown in Fig. 5 to Fig. 8.

Can find out from graph of a relation Fig. 5 to Fig. 8 of the through street oil consumption factor set up and emission factor speed has the trend obviously reduced energy consumption and the increase of all types of emission factor along with speed on through street, maintains a certain numerical value afterwards and is in dynamic balance state.

Because its trend is typical negative power function variation tendency, therefore negative power function is selected to return herein, take speed as independent variable, energy consumption and all types of emission factor are that dependent variable sets up regression function, namely based on the model formation of the section oil consumption emission factor speed correction model of VSP, formula is as follows:

$y={\mathrm{\&alpha;}}_1\&CenterDot;{v_a}^{{\mathrm{\&beta;}}_1}$

In formula, v _athe average velocity on a of section, unit km/h; Y is oil consumption emission factor, and unit is ml/km or g/km; α ₁, β ₁for oil consumption emission factor velocity fitting coefficient, α ₁, β ₁according to each oil consumption factor of correspondence under each speed interval or the emission factor EF of pollutant _j,kwith the negative power function value of the graph of a relation matching of average velocity.

Average velocity v on the section a that step S1.1 is tried to achieve _asubstitute into the model formation based on the oil consumption emission factor speed correction model of VSP, thus the relation set up on a of section between flow and driving trace, this formula is connected with traffic energy consumption emission factor velocity model building, finally obtain the relational model between " the average bicycle discharge " of point road type and link flow, i.e. section eco-resi stance model.

Due to NO _xemission factor is relatively poor with the variation tendency of speed, and the degree of fitting of curve is not high, so here to NO _xthe speed correction model piecewise fitting function of emission factor, when speed is lower, still selects negative power function to return, and when speed is higher, then carries out recurrence with polynomial function and improves degree of fitting.

Table 1 is traffic energy consumption emission factor speed correction model, oil consumption emission factor velocity fitting factor alpha ₁, β ₁value according to the oil consumption emission factor EF of each pollutant corresponding under each speed interval _i,kwith the graph of a relation matching of average velocity negative power function out and determining, degree of fitting is that the curve simulated according to Excel obtains with actual Data Comparison.

Table 1 traffic energy consumption emission factor speed correction model

Step2, set up node eco-resi stance model;

Model construction thinking: incur loss through delay formula according to Webster and utilize the operation characteristic data of vehicle and the attribute data of crossing to try to achieve the delay of crossing, try to achieve the average stop frequency of vehicle further.Add up the VSP distribution of different delay value under the different stop frequency of different intersection type, afterwards in conjunction with the rate of fuel consumption of vehicle under each VSP Bin and emission index, calculate vehicle each average fuel consumption factor of incuring loss through delay and emission factor under the different stop frequency of different intersection type.On the basis of model construction, finally according to the basic oil consumption Summing Factor emission factor of different intersection type, and each average fuel consumption of incuring loss through delay and emission factor under different stop frequency, obtain the oil consumption of each delay and the delay correction factor of emission factor by following formulae discovery, also just establish the discharge of average bicycle and crossing flow (arrival rate), the relational model of a left side directly between right turn, signal period length, split.

Step Step2 specifically comprises following sub-step:

Step2.1, calculating intersection delay t _p:

The people such as the F.V.Webster of TRRL research institute of Britain in 1958 propose according to waiting line theory theory the model calculating intersection delay.Mainly comprise two parts in this model, the normal phase place that a part is vehicle arriving rate to be produced when being fixing average is incured loss through delay and uniform delay, the additional delay produced when another part is vehicle arriving rate random fluctuation.Its concrete form is:

$t_p=\frac{T{(1-\mathrm{\&lambda;})}^2}{2(1-\mathrm{\&lambda;X})}+\frac{X^2}{2Q(1-X)}-0.65{\left(\frac{T}{Q^1}\right)}^{\frac{1}{3}}{X}^{(2+5\mathrm{\&lambda;})}$

In formula, T is signal period length; λ is entrance driveway effective green time and signal period length ratio, i.e. split; Q is the magnitude of traffic flow of entrance driveway; X is saturation degree, and X=Q/S, S are entrance driveway handling capacity.

Above formula be Webster on the basis of Monter-Carlo analog result, correct the delay formula form that the traffic engineers that gone out by waiting line theory theory deduction are originally conventional.

The average stop frequency of Step2.2, calculating signal period each car interior;

The average stop frequency h of crossing w phase place vehicle _wfor

$h_w=\underset{r}{\mathrm{\&Sigma;}}0.9\frac{C-C_{\mathrm{ew}}}{1-y_{\mathrm{wr}}}$

In formula, C _ewfor the effective green time of crossing w phase, y _wrfor the throughput ratio of r entrance driveway of crossing w phase.

In the signal period of old friend's prong, the average stop frequency of each car is:

$H=\underset{w=1}{\mathrm{\&Sigma;}}{h}_w{q}_w/\underset{w=1}{\mathrm{\&Sigma;}}{q}_w$

In formula, q _wfor the flow of crossing w phase.

Step2.3, set up crossing oil consumption emission factor incur loss through delay correction model, as node eco-resi stance model:

Here propose to take VSP as intermediate variable, oil consumption discharge is associated with delay.First based on a large amount of oil consumption discharge measured data, statistics obtains the rate of fuel consumption of vehicle under each VSP Bin and emission index.Then the operation characteristic data based on actual measurement obtain the VSP distribution character of vehicle under the different stop frequency (being the average stop frequency of each car in the signal period) of different intersection type, take VSP as the oil consumption Summing Factor emission factor that bridge calculates vehicle each delay value under the different stop frequency of different intersection type.Select to incur loss through delay be oil consumption under 0 and emission factor as basic oil consumption and emission factor, analyze and incur loss through delay and vehicle oil consumption and the relation between discharge, thus set up the delay correction model under different intersection type difference stop frequency.

The ultimate principle incuring loss through delay correction model is: by calculating the basic emission factor of different intersection type, and the average emission factors under different delay, analyzes the impact of incuring loss through delay vehicular discharge, thus sets up the correction model incured loss through delay emission factor.

Step Step2.3 comprises following sub-step:

Step2.3.1, the basic emission factor in calculating crossing:

Determine the basic emission factor of vehicle in crossing, as the basis of incuring loss through delay correction model.The computing formula of the basic emission factor in crossing is as follows:

${\mathrm{EF}}_m=({\mathrm{\&Sigma;}}_{-15}^{15}{\mathrm{ER}}_i\&times;D_i)\&times;\frac{T_m}{L_m}\&times;1000$

In formula, EF _bfor basic oil consumption emission factor, unit is g/km; ER _ibe the oil consumption emission index in i-th interval unit VSP Bin, unit is g/s; D _iit is the Annual distribution ratio in i-th VSP interval; L _bfor vehicle is in the total kilometres in this section, unit is m; T _bfor vehicle is at the overall travel time in this section, unit is s.

Set up the delay correction model of vehicle in crossing, namely to the generation of incuring loss through delay, vehicle is revised in the extra increase of crossing's oil consumption and discharge, when therefore selecting D Bin to be 0s herein, the operational process of vehicle is as the basic operational process of vehicle in crossing.The Research Thinking of the computing method of basic oil consumption and emission factor is:

First, the determination of the basic driving cycle of the vehicle of different intersection type.Choose the cycle of operation of vehicle when D Bin is 0s, as the basic driving cycle of different intersection type vehicle.Utilize the delay and the VSP value that calculate vehicle by gps data second that gather, then utilize the VSP Bin division methods of foundation to divide VSP distributed area, calculate the distributive law of each VSP Bin.

Secondly, the calculating of emission index.A large amount of emissions datas of the vehicle namely collected for PEMS, utilize VSP class statistic method, carry out the arrangement of data, classification, process, analysis, finally obtain the emission index of each VSP Bin.

Finally, take VSP as bridge, on the basis of the emission index under the VSP Bin distributive law of basic driving cycle obtaining each intersection type and each VSP Bin, utilizing the basic emission factor that formulae discovery obtains at different intersection type vehicle, incuring loss through delay as carrying out emission factor the benchmark revised.

Step2.3.2, calculate average fuel consumption emission factor corresponding to each intersection delay:

The computing method of the average emission factors under different delay are:

${\mathrm{EF}}_m=({\mathrm{\&Sigma;}}_{-15}^{15}{\mathrm{ER}}_i\&times;D_i)\&times;\frac{T_m}{L_m}\&times;1000$

In formula, EF _mincur loss through delay for oil consumption emission factor during m, unit is g/km; ER _ibe rate of fuel consumption and the emission index of i-th interval unit VSPBin, unit is g/s; D _ifor incuring loss through delay the Annual distribution ratio for i-th interval unit VSPBin during m; L _mfor incuring loss through delay the crossing size for m, crossing length in other words, unit is m; T _mfor incuring loss through delay the overall travel time of the intersection vehicles for m, unit is s.

According to above computing formula and combine above about the elaboration of emitted smoke model, the calculating thinking of the average fuel consumption emission factor that different intersection delay is corresponding is:

First, basic data and process is collected.Utilize the actual operating mode data of GPS collection vehicle, then utilize MapInfo software, filter out the operating condition data in the analyzed area of crossing, a point different intersection type carries out data preparation and pre-service.

Then, delay and the stop frequency of vehicle is calculated.The delay of sing on web ster delay estimation formulae discovery vehicle, and carry out Classifying Sum according to the different stop frequency of different intersection type.

Then, the VSP distribution of incuring loss through delay under different stop frequency is set up.By the crossing analyzed area filtered out by gps data second, calculate by VSP value second, utilize the VSP Bin division methods proposed to divide VSP distribution that then VSP Bin adds up different delay value under the different stop frequency of different intersection type.

Finally, in conjunction with the rate of fuel consumption of vehicle under each VSP Bin and emission index, calculate vehicle each average fuel consumption factor of incuring loss through delay and emission factor under the different stop frequency of different intersection type.

The delay correction factor of Step2.3.3, the oil consumption calculating each intersection delay and emission factor:

On the basis of model construction, according to the basic oil consumption emission factor in the crossing of different intersection type, and the average fuel consumption emission factor of each intersection delay under different stop frequency (being the average stop frequency of each car in the signal period), calculate the oil consumption of each delay and the delay correction factor of emission factor, formula is as follows:

SCF _m＝EF _m/EF _b；

In formula, SCF _mfor oil consumption emission factor when intersection delay is m incurs loss through delay correction factor;

Step2.3.4, set up crossing oil consumption emission factor incur loss through delay correction model, as node eco-resi stance model:

The regretional analysis of loose point is carried out to the correction factor of each delay calculated, sets up the delay correction model of vehicle different stop frequency on different intersection type.

The delay correction model of the present embodiment Main Analysis Light-duty Vehicle different stop frequency on secondary-secondary type crossing.

Because the correction factor scatter diagram trend of each delay is typical linear function variation tendency, therefore select linear function to return, to incur loss through delay for independent variable, oil consumption emission factor correction factor is that dependent variable sets up regression function, and function expression is:

y'＝α ₂t _w+β ₂

In formula, t _wfor intersection delay, unit is s; Y ' is that oil consumption emission factor incurs loss through delay correction factor; α ₂, β ₂for oil consumption emission factor incurs loss through delay fitting coefficient, α ₂, β ₂oil consumption emission factor according to different stop frequencies corresponding to each intersection delay incurs loss through delay correction factor SCF _mthe linear function value of scatter diagram matching.

The intersection delay t that step Step2.1 is tried to achieve _wsubstitute into the model formation that oil consumption emission factor in crossing incurs loss through delay correction model, this formula is set up with traffic energy consumption emission factor Delay Model and is connected, finally obtain the relational model between " the average bicycle discharge " of point intersection type and crossing flow, i.e. node eco-resi stance model.

For Light-duty Vehicle in secondary-secondary type crossing, the functional form of model is as table 2:

Table 2 traffic oil consumption emission factor incurs loss through delay correction model

Step3, according to section eco-resi stance model and node eco-resi stance model, calculate the oil consumption emission factor of section eco-resi stance and the oil consumption emission factor of node eco-resi stance, select the traffic route that the oil consumption emission factor sum of the oil consumption emission factor of section eco-resi stance and node eco-resi stance is minimum:

Utilize the information that vehicle mounted guidance terminal and traffic information delivery system provide, provide alternative route, the oil consumption emission data of recycling actual measurement, in conjunction with the eco-resi stance computing method for routing that the present embodiment provides, try to achieve total energy consumption and discharge minimum route, and be finally presented at vehicle mounted guidance terminal, for driver provides best energy-conservation route.Thus the path optimization's algorithm realized towards oil consumption and discharge.

Obviously; the above embodiment of the present invention is only for example of the present invention is clearly described; and be not the restriction to embodiments of the present invention; for those of ordinary skill in the field; can also make other changes in different forms on the basis of the above description; here cannot give exhaustive to all embodiments, every belong to technical scheme of the present invention the apparent change of extending out or variation be still in the row of protection scope of the present invention.

Claims (8)

1., for the eco-resi stance computing method that traffic route is selected, it is characterized in that, the method comprises the steps:

S1, set up section eco-resi stance model, model formation is:

$y={\mathrm{\&alpha;}}_1\&CenterDot;{v_a}^{{\mathrm{\&beta;}}_1}$

In formula, v _afor the average velocity on a of section, unit km/h; Y is oil consumption emission factor, and unit is ml/km or g/km; α ₁, β ₁be oil consumption emission factor velocity fitting coefficient;

S2, set up node eco-resi stance model, model formation is:

y'＝α ₂t _w+β ₂

In formula, t _wfor intersection delay, unit is s; Y ' is oil consumption emission factor delay correction factor; α ₂, β ₂be oil consumption emission factor and incur loss through delay fitting coefficient;

S3, according to section eco-resi stance model and node eco-resi stance model, calculate the oil consumption emission factor of section eco-resi stance and the oil consumption emission factor of node eco-resi stance, select the traffic route that the oil consumption emission factor sum of the oil consumption emission factor of section eco-resi stance and node eco-resi stance is minimum.

2. the eco-resi stance computing method selected for traffic route according to claim 1, it is characterized in that, described step S1 comprises following sub-step further:

S1.1, the average velocity v calculated on a of section _a;

S1.2, set up section oil consumption emission factor speed correction model based on vehicle specific power VSP, as section eco-resi stance model.

3. the eco-resi stance computing method selected for traffic route according to claim 1, it is characterized in that, described step S2 comprises following sub-step further:

S2.1, calculating intersection delay t _w;

The average stop frequency of S2.2, calculating signal period each car interior;

S2.3, set up crossing oil consumption emission factor incur loss through delay correction model, as node eco-resi stance model.

4. the eco-resi stance computing method selected for traffic route according to claim 2, is characterized in that, calculate the average velocity v on a of section in described step S1.1 _aformula be:

$v_a=L_a/t_0[1+\mathrm{\&alpha;}{\left(\frac{q_a}{c_a}\right)}^{\mathrm{\&beta;}}]$

In formula, L _afor the length of section a; t _afor the impedance of section a; t ₀it is zero flow impedance; q _afor the volume of traffic of section a; c _afor the practical tonnage capacity of section a; α, β are retardation factor.

5. the eco-resi stance computing method selected for traffic route according to claim 4, it is characterized in that, step S1.2 comprises sub-step further:

S1.2.1, calculating Light-duty Vehicle are by the instantaneous VSP value of second, and formula is as follows:

VSP＝v·(1.1a`+0.132)+0.000302·v ³

In formula, v be Light-duty Vehicle by speed second, unit is m/s; A` be Light-duty Vehicle by acceleration second, unit is m/s ²;

S1.2.2, be that step-length carries out cluster to the instantaneous VSP value by second with 1kW/t, the instantaneous VSP value by second is divided into interval unit VSPBin according to interval division principle, and formula is as follows:

VSPBin＝i,

In formula, the span of i is the integer between [-20,20];

S1.2.3, be time granularity with 60s, divide short stroke, and calculate the average velocity of each short stroke by averaging to each travel speed of continuous 60s;

S1.2.4, be that step-length carries out interval division to average velocity with 2km/h, judge the speed interval at average velocity place, the data identical to the left end point value Int Speed of all speed intervals carry out cluster, add up total number of the respective number of each interval unit VSP Bin corresponding to the left end point value Int speed of each speed interval and the instantaneous VSP value by second, the distributive law of each VSP Bin under calculating each Int speed, formula is as follows:

$R_{i,k}=\frac{N_{i,k}}{N_k}$

In formula, k is the value of the left end point value Int speed of speed interval; I is the value of interval unit VSP Bin, and span is the integer between [-20,20]; R _{i, k}the distributive law of i-th interval unit VSP Bin when be the left end point value Int Speed of speed interval being k; N _{i, k}by the sum of the instantaneous VSP value of second when be Int Speed being k; N _kwhen be Int Speed being k, interval unit VSP Bin is the instantaneous VSP value number by second of i;

S1.2.5, calculate oil consumption emission factor corresponding to each speed interval, formula is as follows:

${\mathrm{EF}}_{j,k}=\frac{{\mathrm{\&Sigma;}}_i{\mathrm{er}}_{i,j}\&times;R_{i,k}}{k+1}$

In formula, EF _j,kthe emission factor of the jth kind oil consumption factor or pollutant when left end point value Int Speed for speed interval is k, pollutant comprises CO, NO _xand HC; Er _i,jit is the emission index of jth kind rate of fuel consumption or pollutant in i-th interval unit VSP Bin; R _i,kthe distributive law of i-th interval unit VSP Bin when be the left end point value Int Speed of speed interval being k;

S1.2.6, set up section oil consumption emission factor speed correction model based on VSP, as section eco-resi stance model, formula is as follows:

$y={\mathrm{\&alpha;}}_1\&CenterDot;{v_a}^{{\mathrm{\&beta;}}_1}$

In formula, v _athe average velocity on a of section, unit km/h; Y is oil consumption emission factor, and unit is ml/km or g/km; α ₁, β ₁be oil consumption emission factor velocity fitting coefficient, α ₁, β ₁according to each oil consumption factor of correspondence under each speed interval or the emission factor EF of pollutant _j,kwith the negative power function value of the graph of a relation matching of average velocity.

6. the eco-resi stance computing method selected for traffic route according to claim 3, is characterized in that, calculate intersection delay t in described step S2.1 _pformula be:

$t_p=\frac{T{(1-\mathrm{\&lambda;})}^2}{2(1-\mathrm{\&lambda;X})}+\frac{X^2}{2Q(1-X)}-0.65{\left(\frac{T}{Q^2}\right)}^{\frac{1}{3}}{X}^{(2+5\mathrm{\&lambda;})}$

In formula, T is signal period length; λ is entrance driveway effective green time and signal period length ratio; Q is the magnitude of traffic flow of entrance driveway; X is saturation degree, and X=Q/S, S are entrance driveway handling capacity.

7. the eco-resi stance computing method selected for traffic route according to claim 3, it is characterized in that, described step S2.2 comprises following sub-step further:

S2.2.1, calculate the average stop frequency h of w phase place vehicle _w, formula is as follows:

$h_w=\underset{r}{\mathrm{\&Sigma;}}0.9\frac{C-C_{\mathrm{ew}}}{1-y_{\mathrm{wr}}}$

In formula, C _ewfor the effective green time of w phase, y _wrfor the throughput ratio of r entrance driveway of w phase;

The average stop frequency of S2.2.2, calculating signal period each car interior, formula is as follows:

$H=\underset{w=1}{\mathrm{\&Sigma;}}{h}_w{q}_w/\underset{w=1}{\mathrm{\&Sigma;}}{q}_w$

In formula, q _wfor the flow of w phase.

8. the eco-resi stance computing method selected for traffic route according to claim 6, it is characterized in that, step S2.3 comprises following sub-step further:

S2.3.1, the calculating basic emission factor EF in crossing _b, formula is as follows:

${\mathrm{EF}}_b=({\mathrm{\&Sigma;}}_{-15}^{15}{\mathrm{ER}}_i\&times;D_i)\&times;\frac{T_b}{L_b}\&times;1000$

In formula, ER _ibe the oil consumption emission index in i-th interval unit VSPBin, unit is g/s; D _iit is the Annual distribution ratio in i-th VSP interval; L _bfor motor vehicle is in the total kilometres in this section, unit is m; T _bfor motor vehicle is at the overall travel time in this section, unit is s;

S2.3.2, calculate average fuel consumption emission factor EF corresponding to each intersection delay _m, formula is as follows:

${\mathrm{EF}}_m=({\mathrm{\&Sigma;}}_{-15}^{15}{\mathrm{ER}}_i\&times;D_i)\&times;\frac{T_m}{L_m}\&times;1000$

In formula, ER _ibe the rate of fuel consumption emission index of i-th interval unit VSPBin, unit is g/s; D _ifor incuring loss through delay the Annual distribution ratio for i-th interval unit VSPBin during m; L _mfor incuring loss through delay the crossing size for m, unit is m; T _mfor incuring loss through delay the overall travel time of the intersection vehicles for m, unit is s;

The delay correction factor SCF of S2.3.3, the oil consumption calculating each intersection delay and emission factor _m, formula is as follows:

SCF _m＝EF _m/EF _b；

S2.3.4, set up crossing oil consumption emission factor incur loss through delay correction model, as node eco-resi stance model, formula is as follows:

y'＝α ₂t _w+β ₂

In formula, t _wfor intersection delay, unit is s; Y ' is that oil consumption emission factor incurs loss through delay correction factor; α ₂, β ₂be oil consumption emission factor and incur loss through delay fitting coefficient, α ₂, β ₂oil consumption emission factor according to different stop frequencies corresponding to each intersection delay incurs loss through delay correction factor SCF _mthe linear function value of scatter diagram matching.