1. The voltage estimation method based on new energy automobile data interpolation is characterized by comprising the following steps: the method specifically comprises the following steps:

step 1, a new energy automobile cloud platform collects vehicle-mounted voltage, current, SoC data and instrument panel speed data, and performs cleaning and removing operations on the collected data to form a primary data set;

step 2, determining a starting point and an end point of the vehicle in a certain driving process, and determining a route and topographic data which are possibly passed in the driving process according to the electronic map;

and 3, judging which of the following three working conditions is specifically corresponding to different road sections of the vehicle on the way according to the speed data on the way and by combining the voltage data and the current data: a constant speed working condition, an acceleration working condition and a deceleration working condition;

step 4, respectively calculating voltage interpolation values in data acquisition intervals for different working conditions;

and 5, combining the collected voltage data and the calculated voltage interpolation to form a complete voltage curve of the vehicle in the process of the secondary form.

2. The method of claim 1, wherein: the uniform speed working condition, the acceleration working condition and the deceleration working condition are specifically based on the following criteria:

respectively defining the instrument panel speed v corresponding to each sampling time 1 … … n₁,v₂,...,v_nCurrent is I₁,I₂,...,I_nIs defined as U₁,U₂,...,U_nThe subscript denotes the sampling instant, and a constant c;

the working conditions are defined as:

1) and (3) under a uniform working condition: with no change in speed, i.e. v, in the interval 10s_i-v_i-1I is 0 and the voltage and current do not change significantly during this period_i-I_i-10 or U_i-U_i-1＝0；

2) Acceleration condition: the speed increasing within 10s of the front-to-back interval, i.e. v_i-v_i-1>0 and during which the voltage rises, i.e. U, with the current parameters unchanged_i-U_i-1Or, in the case of a constant voltage, the current rises during this time, i.e. I_i-I_i-1>0；

The acceleration condition is specifically subdivided into a variable acceleration condition and a uniform acceleration condition, and is specifically defined as:

a) changing an acceleration working condition: the judgment is carried out by utilizing the abrupt change of the voltage-current curve, namely, the information a of the acceleration of a plurality of frames before and after the acceleration is calculated_i＝(v_i-v_i-1) τ, where τ is the sampling interval between the ith and (i-1) th frames; if a_i≠a_i+1And a is_i+1>a_iDefining the condition as a variable acceleration condition;

b) uniform acceleration condition: if a_iIf the constant is greater than 0, the condition is defined as a uniform acceleration condition;

3) and (3) deceleration working condition: speed decrease i.e. v within 10s of front-to-back interval_i-v_i-1<0 and, with constant current, the voltage drops during this period, i.e. U_i-U_i-1<0, or, with constant voltage parameters, during which the current decreases, i.e. I_i-I_i-1<0；

The deceleration working condition is specifically subdivided into a variable deceleration working condition and a uniform deceleration working condition, and is specifically defined as:

a) and (3) changing the deceleration working condition: calculating the acceleration of a plurality of frames before and after the sudden change of the voltage and current curve, and if the acceleration before and after the sudden change is not equal, defining the situation as a variable acceleration working condition;

b) the uniform deceleration working condition is as follows: if a_iIf the value is constant and less than 0, the condition is defined as a uniform deceleration condition.

3. The method of claim 1, wherein: the step of respectively calculating the voltage interpolation in the data acquisition interval for different working conditions specifically comprises the following steps:

1) interpolation under constant working condition:

constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) A voltage value of 2;

2) interpolation of acceleration conditions:

changing acceleration condition interpolation: the following interpolation is performed taking into account the variation of the voltage curve:

a) if the period voltage curve is concave, i.e.Taking 99% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

b) if the period voltage curve is convex, i.e.Taking 101% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

interpolation under uniform acceleration conditions: and constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) A voltage value of 2;

3) interpolation under a deceleration working condition:

changing deceleration working condition interpolation: the following interpolation is performed taking into account the variation of the voltage curve:

a) if the period voltage curve is convex decreasing, i.e.Taking 99% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

b) if the period voltage curve is concave, i.e. decreasingTaking 101% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

interpolation under the condition of uniform deceleration: and constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) Voltage value of 2.

4. The method of claim 1, wherein: and (3) matching the working conditions corresponding to different road sections in the driving process determined in the step (3) with the route which is determined by the electronic map and is possibly passed in the driving process and the topographic data, and determining the actual driving route of the vehicle.

Background

With the increasing popularization of new energy automobiles, real-time fault diagnosis for a vehicle power system becomes more and more important. At present, indexes influencing the vehicle performance and the working state, such as the state of charge (SoC) of the power battery, the state of health (SoH) and the like, are lack of direct measurement means, so that at the present stage, obtaining accurate battery working parameters such as voltage and the like still has very important significance for accurately estimating the state of the power battery. The new source automobile has obvious advantages in the aspect of real automobile data acquisition and processing compared with the traditional fuel oil automobile, if the new source automobile can be effectively utilized, a plurality of functions which cannot be achieved before can be achieved, for example, along with the establishment of a new energy automobile cloud platform, the monitoring of the driving track of a single automobile is more convenient, and the working condition change corresponding to different tracks is also beneficial to improving the accuracy of voltage estimation. The method is limited by the limit of data acquisition and processing cost, and the voltage curve is estimated in a mode of combining interval acquisition and interpolation in the engineering, but the existing interpolation means are mainly based on the mathematical theory, so that various complex influence factors in the actual running of the vehicle are ignored. Therefore, how to estimate the voltage by combining the actual vehicle condition of the new energy vehicle is an urgent technical problem to be solved in the prior art.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention provides a voltage estimation method based on new energy automobile data interpolation, which specifically comprises the following steps:

step 1, a new energy automobile cloud platform collects vehicle-mounted voltage, current, SoC data and instrument panel speed data, and performs cleaning and removing operations on the collected data to form a primary data set;

step 2, determining a starting point and an end point of the vehicle in a certain driving process, and determining a route and topographic data which are possibly passed in the driving process according to the electronic map;

and 3, judging which of the following three working conditions is specifically corresponding to different road sections of the vehicle on the way according to the speed data on the way and by combining the voltage data and the current data: a constant speed working condition, an acceleration working condition and a deceleration working condition;

step 4, respectively calculating voltage interpolation values in data acquisition intervals for different working conditions;

and 5, combining the collected voltage data and the calculated voltage interpolation to form a complete voltage curve of the vehicle in the process of the secondary form.

Further, the constant speed working condition, the acceleration working condition and the deceleration working condition are specifically based on the following criteria:

respectively defining the instrument panel speed v corresponding to each sampling time 1 … … n₁,v₂,...,v_nCurrent is I₁,I₂,...,I_nIs defined as U₁,U₂,...,U_nThe subscript denotes the sampling instant, and a constant c;

the working conditions are defined as:

1) and (3) under a uniform working condition: with no change in speed, i.e. v, in the interval 10s_i-v_i-1I is 0 and the voltage and current do not change significantly during this period_i-I_i-10 or U_i-U_i-1＝0；

2) Acceleration condition: the speed increasing within 10s of the front-to-back interval, i.e. v_i-v_i-1>0 and during which the voltage rises, i.e. U, with the current parameters unchanged_i-U_i-1Or, in the case of a constant voltage, the current rises during this time, i.e. I_i-I_i-1>0；

The acceleration condition is specifically subdivided into a variable acceleration condition and a uniform acceleration condition, and is specifically defined as:

a) changing an acceleration working condition: using abrupt change of voltage-current curve to judge, i.e. calculating several frame accelerations before and afterDegree information a_i＝(v_i-v_i-1) τ, where τ is the sampling interval between the ith and (i-1) th frames; if a_i≠a_i+1And a is_i+1>a_iDefining the condition as a variable acceleration condition;

b) uniform acceleration condition: if a_iIf the constant is greater than 0, the condition is defined as a uniform acceleration condition;

3) and (3) deceleration working condition: speed decrease i.e. v within 10s of front-to-back interval_i-v_i-1<0 and, with constant current, the voltage drops during this period, i.e. U_i-U_i-1<0, or, with constant voltage parameters, during which the current decreases, i.e. I_i-I_i-1<0；

The deceleration working condition is specifically subdivided into a variable deceleration working condition and a uniform deceleration working condition, and is specifically defined as:

a) and (3) changing the deceleration working condition: calculating the acceleration of a plurality of frames before and after the sudden change of the voltage and current curve, and if the acceleration before and after the sudden change is not equal, defining the situation as a variable acceleration working condition;

b) the uniform deceleration working condition is as follows: if a_iIf the value is constant and less than 0, the condition is defined as a uniform deceleration condition.

Further, the step of calculating the voltage interpolation in the data acquisition interval respectively for different working conditions specifically includes:

1) interpolation under constant working condition:

constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) A voltage value of 2;

2) interpolation of acceleration conditions:

changing acceleration condition interpolation: the following interpolation is performed taking into account the variation of the voltage curve:

a) if the period voltage curve is concave, i.e.Get the centerTaking 99% of the voltage mean value in 30s before and after the intermediate time as a voltage value at the intermediate time;

b) if the period voltage curve is convex, i.e.Taking 101% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

interpolation under uniform acceleration conditions: and constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) A voltage value of 2;

3) interpolation under a deceleration working condition:

changing deceleration working condition interpolation: the following interpolation is performed taking into account the variation of the voltage curve:

a) if the period voltage curve is convex decreasing, i.e.Taking 99% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

b) if the period voltage curve is concave, i.e. decreasingTaking 101% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

interpolation under the condition of uniform deceleration: and constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) Voltage value of 2.

Furthermore, matching the working conditions corresponding to different road sections in the driving process determined in the step 3 with the route which is determined by the electronic map and the topographic data and is possible to pass through in the driving process, and determining the actual driving route of the vehicle.

The method provided by the invention improves the voltage data acquisition and prediction mode of the existing new energy automobile, considers various working conditions experienced by the automobile in the actual running route on the basis of the traditional interpolation means based on the mathematical theory, and effectively improves the prediction precision of the voltage curve. The driving route acquired by an electronic map or a satellite navigation platform can be calibrated through the calculation result of the voltage, and the accurate determination of the driving track of the vehicle is realized in a very convenient and fast mode on the premise of not acquiring and calculating complex navigation data, so that the invention has a plurality of beneficial effects which are not possessed by the prior art.

Drawings

FIG. 1 is a schematic flow chart of the method of the present invention.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a voltage estimation method based on new energy automobile data interpolation, which specifically comprises the following steps as shown in figure 1:

step 1, a new energy automobile cloud platform collects vehicle-mounted voltage, current, SoC data and instrument panel speed data, and performs cleaning and removing operations on the collected data to form a primary data set; the optional implementation manner is as follows: the battery management system transmits the acquired voltage, current, SoC data and speed information in the instrument panel to the vehicle-mounted terminal TBOX through a CAN bus measuring and transmitting mode, and the vehicle-mounted terminal TBOX is transmitted to the new energy automobile cloud platform through a network connection mode of a wireless network. And carrying out operations such as cleaning and removing on the obtained original data to form a primary data set.

Step 2, determining a starting point and an end point of the vehicle in a certain driving process, and determining a route and topographic data which are possibly passed by the vehicle in the driving process according to an electronic map such as a Gagde map APP;

and 3, judging which of the following three working conditions is specifically corresponding to different road sections of the vehicle on the way according to the speed data on the way and by combining the voltage data and the current data: a constant speed working condition, an acceleration working condition and a deceleration working condition;

step 4, respectively calculating voltage interpolation values in data acquisition intervals for different working conditions;

and 5, combining the collected voltage data and the calculated voltage interpolation to form a complete voltage curve of the vehicle in the process of the secondary form.

In a preferred embodiment of the present invention, the constant speed condition, the acceleration condition, and the deceleration condition are specifically based on the following criteria:

respectively defining the instrument panel speed v corresponding to each sampling time 1 … … n₁,v₂,...,v_nCurrent is I₁,I₂,...,I_nIs defined as U₁,U₂,...,U_nThe subscript denotes the sampling instant, and a constant c;

the working conditions are defined as:

1) and (3) under a uniform working condition: with no change in speed, i.e. v, in the interval 10s_i-v_i-1I is 0 and the voltage and current do not change significantly during this period_i-I_i-10 or U_i-U_i-1＝0；

2) Acceleration condition: the speed increasing within 10s of the front-to-back interval, i.e. v_i-v_i-1>0, and in the case of a constant current parameter, the voltage rises during this period, i.e. U_i-U_i-1Or, in the case of a constant voltage, the current rises during this time, i.e. I_i-I_i-1>0；

The acceleration condition is specifically subdivided into a variable acceleration condition and a uniform acceleration condition, and is specifically defined as:

a) changing an acceleration working condition: the judgment is carried out by utilizing the abrupt change of the voltage-current curve, namely, the information a of the acceleration of a plurality of frames before and after the acceleration is calculated_i＝(v_i-v_i-1) τ, where τ is the sampling interval between the ith and (i-1) th frames; if a_i≠a_i+1And a is_i+1>a_iDefining the condition as a variable acceleration condition;

b) uniform acceleration condition: if a_iIf the constant is greater than 0, the condition is defined as a uniform acceleration condition;

3) and (3) deceleration working condition: speed decrease i.e. v within 10s of front-to-back interval_i-v_i-1<0 and, with constant current, the voltage drops during this period, i.e. U_i-U_i-1<0, or, with constant voltage parameters, during which the current decreases, i.e. I_i-I_i-1<0；

The deceleration working condition is specifically subdivided into a variable deceleration working condition and a uniform deceleration working condition, and is specifically defined as:

a) and (3) changing the deceleration working condition: calculating the acceleration of a plurality of frames before and after the sudden change of the voltage and current curve, and if the acceleration before and after the sudden change is not equal, defining the situation as a variable acceleration working condition;

b) the uniform deceleration working condition is as follows: if a_iIf the value is constant and less than 0, the condition is defined as a uniform deceleration condition.

The step of respectively calculating the voltage interpolation in the data acquisition interval for different working conditions specifically comprises the following steps:

1) interpolation under constant working condition:

constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) A voltage value of 2;

2) interpolation of acceleration conditions:

changing acceleration condition interpolation: the following interpolation is performed taking into account the variation of the voltage curve:

a) if the period voltage curve is concave, i.e.The mean voltage value of 99% in 30s before and after the intermediate time is taken as the intermediate timeVoltage value of (d);

b) if the period voltage curve is convex, i.e.Taking 101% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

interpolation under uniform acceleration conditions: and constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) A voltage value of 2;

3) interpolation under a deceleration working condition:

changing deceleration working condition interpolation: the following interpolation is performed taking into account the variation of the voltage curve:

a) if the period voltage curve is convex decreasing, i.e.Taking 99% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

b) if the period voltage curve is concave, i.e. decreasingTaking 101% of the voltage mean value in 30s before and after the intermediate time as the voltage value of the intermediate time;

interpolation under the condition of uniform deceleration: and constructing a voltage-time linear relation based on linear interpolation:determining the value of k, and performing linear fitting to determine the intermediate time t ═ t (t)_i+t_i-1) Voltage value of 2.

For some real driving routes, a plurality of adjacent optional routes exist, but due to various differences of terrain, road surface conditions and the like, different working conditions can be caused, but the differences are limited by the precision differences of an electronic map or a navigation platform, a plurality of routes can be identified as the same route, and at the moment, if an accurate actual driving route is to be obtained, positioning data processing and calculation with higher precision are required, and the calculation power consumption is obviously improved. Therefore, in a preferred embodiment of the present invention, the actual driving route of the vehicle is determined by matching the behavior corresponding to the different sections during driving determined in step 3 with the route and the topographic data that may be passed during driving determined by the electronic map.

In a preferred embodiment of the present invention, 1500 frames of data are selected to perform the method provided by the present invention, and the present invention can achieve a higher accuracy level by comparing the voltage calculated by the new energy vehicle big data platform based on the collected data.

It should be understood that, the sequence numbers of the steps in the embodiments of the present invention do not mean the execution sequence, and the execution sequence of each process should be determined by the function and the inherent logic of the process, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.