CN103234544A - Methods for building power consumption factor model and estimating following-up driving range of electric car - Google Patents

Abstract

The invention discloses methods for building a power consumption factor model and estimating following-up driving range of an electric car. The model building method comprises the following steps of: introducing aggregate variable, calculating a comprehensive variable value of per second based on the instantaneous speed and acceleration of the electric car obtained in advance; forming a basic database by combining corresponding power consumption rate of per second; dividing a driving segment according to a certain time interval; counting the mean speed of each segment; merging the comprehensive variable value of the driving segment at the same mean speed; counting a distribution law, and calculating the average power consumption rate of per kilometer, namely a power consumption factor; and determining the final electric car power consumption factor model based on the mean speed by applying a mathematical statistic method according to the counted mean speed and the power consumption factor. The invention simultaneously discloses a method for estimating following-up driving range of the electric car.

Description

Electric automobile electric quantity consumption factor model is set up and the continual mileage evaluation method

Technical field

The present invention relates to the electric vehicle engineering field, relate in particular to electric automobile electric quantity consumption factor model and set up and the continual mileage evaluation method.

Background technology

Along with the recoverable amount of fuel-engined vehicle increases sharply, the environmental pollution and the exhausted problem of global fuel oil that are caused by fuel-engined vehicle are also serious day by day.Electric automobile has been subjected to increasing attention because having low energy consumption, low noise, energy utilization rate height, simple in structure and for ease of maintenaince wait characteristics.At present, electric automobile is subjected to the restriction of battery capacity and distance travelled, needs repeatedly to charge in the trip process, and therefore reasonably path planning and navigation seem particularly necessary.And as the condition precedent of electric automobile path planning and navigation, continual mileage is estimated also more and more to receive publicity accurately.Existing method of estimation is not considered the relation between real traffic behavior and the electric automobile continual mileage, makes estimated result accurate inadequately.In view of microcosmic such as instantaneous velocity and the acceleration problem of difficult parameters to obtain of travelling, the present invention proposes the electric automobile continual mileage evaluation method based on road-section average speed, strengthened the practicality of method.

Summary of the invention

The technical matters that the present invention solves is how accurately to estimate the electric automobile continual mileage, for path planning and navigation algorithm provide foundation.

The embodiment of the invention discloses a kind of electric automobile electric quantity consumption factor model method for building up, may further comprise the steps:

1) introduces generalized variable, based on the electric automobile instantaneous velocity and the acceleration that obtain in advance, calculate the generalized variable value of per second, form basic database in conjunction with corresponding per second electric quantity consumption rate;

2) divide the fragment of travelling according to certain time interval, add up the average velocity of each fragment;

3) the generalized variable value under the fragment of travelling of identical average velocity is merged, add up its regularity of distribution, and calculate its electric quantity consumption rate of average every kilometer, i.e. electric quantity consumption factor;

4) average velocity and the electric quantity consumption factor that obtains according to statistics used mathematical statistic method, determines the final electric automobile electric quantity consumption factor model based on average velocity.

Further, as preferably, described generalized variable comprises: traffic behavior, road grade, electric motor car weight, windshield and resistance to rolling, A=f (V, a, grade, m, S, C), wherein, A is generalized variable; V is the electric automobile instantaneous velocity; A is the electric automobile instantaneous acceleration; Grade is the gradient; M is the electric automobile quality; S is the electric automobile area that keeps out the wind; C is resistance to rolling.

The invention also discloses a kind of electric automobile continual mileage evaluation method, may further comprise the steps:

1) according to the traffic behavior in the path planning that obtains in advance and road network future, extracts the average velocity that obtains the path planning respective stretch; Wherein, path planning is to be calculated by path planning algorithm under the situation of not considering midway to charge; The average velocity in highway section future can calculate by the prediction of short-term traffic volume method;

2) according to the method for claim 1 or 2, obtain electric automobile electric quantity consumption factor model;

3) the electric automobile electric quantity consumption factor model that the average velocity substitution in highway section is set up calculates the electric quantity consumption factor;

Obtain the dump energy of current battery, in conjunction with the electric quantity consumption factor, obtain remaining mileage through cycle calculations.

The present invention is directed to real road driving environment, both considering the microcosmic influence of parameter to the electric automobile continual mileage of travelling, consider again under the situation of practice, by introducing generalized variable, set up the electric automobile electric quantity consumption factor model based on average velocity, when guaranteeing model accuracy, simplify needed input variable, increased the practicality of model.Based on the electric quantity consumption factor model, a kind of electric automobile continual mileage method of estimation based on road-section average speed has been proposed, be implemented under the real roads running environment the accurate estimation to the electric automobile continual mileage, and then provide the data basis for the realization of user's trip, path planning and navigation algorithm.

Description of drawings

When considered in conjunction with the accompanying drawings, by the reference following detailed, can more completely understand the present invention better and learn wherein many attendant advantages easily, but accompanying drawing described herein is used to provide further understanding of the present invention, constitute a part of the present invention, illustrative examples of the present invention and explanation thereof are used for explaining the present invention, do not constitute to improper restriction of the present invention, wherein:

Fig. 1 is the process flow diagram of the electric automobile continual mileage evaluation method that provides of present embodiment.

Fig. 2 is the concrete process flow diagram that calculates of continual mileage that present embodiment provides.

Embodiment

Describe with reference to the embodiments of the invention of Fig. 1-2.

For above-mentioned purpose, feature and advantage can be become apparent more, the present invention is further detailed explanation below in conjunction with the drawings and specific embodiments.

As shown in Figure 1, the electric automobile continual mileage method of estimation that present embodiment provides may further comprise the steps:

S11, obtain the average velocity in each highway section;

S12, obtain path planning;

S13, according to the average velocity in the path planning that obtains in advance and highway section future, extract the average velocity that obtains the path planning respective stretch

, unit is km/h; Path planning is to be calculated by path planning algorithm under the situation of not considering midway to charge; The average velocity in highway section future can calculate by the traffic forecast method;

S14, with the electric automobile electric quantity consumption factor model that the average velocity substitution in highway section has been set up, calculate electric quantity consumption factor q, unit is C/km;

$q=12511.049/\stackrel{\‾}{V}-18.066\·\stackrel{\‾}{V}+0.159\·{\stackrel{\‾}{V}}^2+1846.27;$

S15, obtain the remaining capacity SOC of current battery _r

S16, according to SOC _rWith electric quantity consumption factor q, obtain remaining mileage S through cycle calculations, unit is km.

The concrete calculation process of remaining mileage S as shown in Figure 2.

S21, acquisition electric automobile remaining capacity SOC _r

S22, according to the direction of Origin And Destination, the highway section in the path planning is numbered k (k=1,2,3 ...), make initial k=1, S=0;

The length L in S23, extraction k bar highway section _kAnd following average velocity;

S24, substitution electric quantity consumption factor model calculate every kilometer electric quantity consumption;

Total electric weight Q that S25, calculating k bar highway section consume _k=q _kL _k

S26, judge whether SOC _rQ _kIf then carry out S27, SOC _r=SOC _r-Q _k, S=S+L _k, k=k+1 jumps to step S23 then; Otherwise carry out S28, continual mileage S=S+SOC _r/ q _kS29, calculating electric automobile continual mileage S.

Wherein, the electric quantity consumption factor model is set up by the following method among the S14:

1) by introducing generalized variable (being example with motor vehicle specific power (VSP) in this example), the factor that traffic behavior, road grade, electric motor car weight and windshield etc. is influenced power consumption combines.Based on the instantaneous electric automobile during traveling data that obtain in advance, the VSP(unit of calculating per second is kw/t simultaneously), form basic database in conjunction with corresponding per second electric quantity consumption rate.

$\begin{array}{c}\mathrm{VSP}=V\·[a+g\·\mathrm{grad}e+g\·C_R]+\frac{1}{2}{\mathrm{\ρ}}_{\mathrm{\σ}}\frac{C_D\·S}{m}{V}^3\\ =V\·(1.1\·a+0.132)+0.000302\·V^3\end{array}$

Wherein, V is the electric automobile instantaneous velocity, km/h; A is the electric automobile instantaneous acceleration, m/s ²G is acceleration of gravity, gets 9.81m/s ²Grade is road grade, dimensionless; C _R---coefficient of rolling resistance, dimensionless gets 0.0135; ρ _σBe atmospheric density, get 1.207kg/m in the time of 20 ℃ ³C _DBe air resistance coefficient, dimensionless; S is cross-sectional area before the vehicle, m ²M is car weight, kg, wherein (C _D* S)/m integral body is taken as 0.0005.

2) based on basic database, divide the VSP-Bin value with 1kw/t, calculate the corresponding VSP-Bin value of VSP: [n, n+1), so Dui Ying VSP-Bin value is n kw/t if VSP is ∈.And add up the electric quantity consumption rate { I of the average per second of each VSP-Bin correspondence ₁, I ₂, I ₃..., I _j, unit is C/s;

3) be to divide the fragment of travelling at interval with 30s, add up the average velocity of each fragment

4) with average velocity Be to be divided into different speed intervals at interval with 3.6km/h, the fragment of will respectively travelling is included in the corresponding speed interval, adds up the VSP-Bin regularity of distribution in each speed interval, and calculates the electric quantity consumption rate of average per second according to following formula.

${\stackrel{\‾}{I}}_i=\underset{j}{\mathrm{\Σ}}{I}_j\×D_{\mathrm{ij}}$

Wherein,

Be the electric quantity consumption rate of average per second under the interval i of average velocity, A; I _jBe the electric quantity consumption rate of average per second under j the VSP-Bin, A; D _IjBe j number percent that VSP-Bin is shared under the interval i of average velocity, %.

Simultaneously, utilize following formula that the electric quantity consumption rate of average per second is converted into average every kilometer electric quantity consumption rate, i.e. electric quantity consumption factor q.

$q_i=\frac{{\stackrel{\‾}{I}}_i\underset{k=1}{\overset{n}{\mathrm{\Σ}}}{T}_k/3600}{\underset{k=1}{\overset{n}{\mathrm{\Σ}}}{L}_k}$

Wherein, q _iBe the electric quantity consumption factor under the interval i of average velocity, C/km; T _kBe the running time of fragment k under the interval i of average velocity, s; L _kDistance travelled for fragment k under the interval i of average velocity.

5) average velocity and the electric quantity consumption factor that obtains according to statistics used regression model, determines the final electric automobile electric quantity consumption factor model based on average velocity, shown in the formula specific as follows.

$q=a/\stackrel{\‾}{V}+b\·\stackrel{\‾}{V}+c\·{\stackrel{\‾}{V}}^2+d=12511.049/\stackrel{\‾}{V}-18.066\·\stackrel{\‾}{V}+0.159\·{\stackrel{\‾}{V}}^2+1846.27.$

Though more than described the specific embodiment of the present invention, but those skilled in the art is to be understood that, these embodiments only illustrate, those skilled in the art can carry out various omissions, replacement and change to the details of said method and system under the situation that does not break away from principle of the present invention and essence.For example, merge the said method step, then belong to scope of the present invention thereby carry out the essence identical functions according to the identical method of essence to realize the identical result of essence.Therefore, scope of the present invention is only limited by appended claims.

Claims (3)

1. an electric automobile electric quantity consumption factor model method for building up is characterized in that, may further comprise the steps:

1) introduces generalized variable, based on the electric automobile instantaneous velocity and the acceleration that obtain in advance, calculate the generalized variable value of per second, form basic database in conjunction with corresponding per second electric quantity consumption rate;

2) divide the fragment of travelling according to certain time interval, add up the average velocity of each fragment;

3) the generalized variable value under the fragment of travelling of identical average velocity is merged, add up its regularity of distribution, and calculate its electric quantity consumption rate of average every kilometer, i.e. electric quantity consumption factor;

4) average velocity and the electric quantity consumption factor that obtains according to statistics used mathematical statistic method, determines the final electric automobile electric quantity consumption factor model based on average velocity.

2. according to the described electric automobile electric quantity consumption of claim 1 factor model method for building up, it is characterized in that described generalized variable also comprises: traffic behavior, road grade, electric motor car weight, windshield and resistance to rolling, A=f (V, a, grade, m, S, C), wherein, A is generalized variable; V is the electric automobile instantaneous velocity; A is the electric automobile instantaneous acceleration; Grade is the gradient; M is the electric automobile quality; S is the electric automobile area that keeps out the wind; C is resistance to rolling.

3. an electric automobile continual mileage evaluation method is characterized in that, may further comprise the steps:

1) according to the traffic behavior in the path planning that obtains in advance and road network future, extracts the average velocity that obtains the path planning respective stretch; Wherein, path planning is to be calculated by path planning algorithm under the situation of not considering midway to charge; The average velocity in highway section future can calculate by the prediction of short-term traffic volume method;

2) according to the method for claim 1 or 2, obtain electric automobile electric quantity consumption factor model;

3) the electric automobile electric quantity consumption factor model that the average velocity substitution in highway section is set up calculates the electric quantity consumption factor;

4) obtain the dump energy of current battery, in conjunction with the electric quantity consumption factor, obtain remaining mileage through cycle calculations.

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