A method, system, medium and equipment for evaluating energy efficiency of new energy vehicle components

Abstract

The present invention discloses a method and system, medium and equipment for evaluating the energy efficiency of new energy vehicle components. The method comprises the following steps: collecting power calculation parameters of the components to be tested and marking the cycle working conditions; dividing the measured power of the components to be tested by the rated power according to the collected power calculation parameters to obtain the load rate at equal time intervals; calculating the probability density distribution value of the working condition section based on the load rate; calculating the weight coefficient of each working condition section according to the probability density distribution value; calculating the average efficiency of the components to be tested according to the working condition section; multiplying the average efficiency of each working condition section by the corresponding weight coefficient to obtain the first i The scheme of the present invention comprehensively considers the influence of the number of cycles and the operating conditions on the measured components, analyzes and evaluates the energy consumption of the measured components from the perspective of load rate, and has a smaller granularity and more dimensional evaluation angles than the existing evaluation methods.

Description

Technical Field

[0001] The present invention relates to the technical field of energy efficiency evaluation of new energy vehicle components, and in particular to a method, system, medium and equipment for energy efficiency evaluation of new energy vehicle components. Background Art

[0002] As the penetration rate of new energy vehicles in the passenger car and commercial vehicle markets continues to rise, drivers and passengers have higher expectations for the intelligence and electrification of new energy vehicles, and there are more and more on-board electrical equipment, which leads to higher requirements for the energy efficiency of various components on the vehicle. From the perspective of car companies, while meeting the driving comfort, they must also ensure a high driving range, which requires low energy consumption and high efficiency of on-board electrical components. In the cycle test, the energy efficiency of components is an important indicator for evaluating the economy of the vehicle. How to improve and optimize energy efficiency is also an important means to promote energy conservation and consumption reduction of new energy vehicles. However, there is currently a lack of a scientific and reasonable evaluation method for the energy consumption test results of components in the cycle conditions of new energy vehicles. Especially for components that work continuously in multiple cycle conditions, the current evaluation method lacks consideration of the operating condition section, component temperature, etc. The efficiency obtained is mostly for one or more complete conditions, and the rated power of different models is different. The horizontal comparison results between different components are not accurate enough and the reference value is low. Summary of the invention

[0003] The purpose of the present invention is to provide a method and system, medium and equipment for evaluating the energy efficiency of new energy vehicle components, which avoids the problems of the generality of existing evaluation methods and the large gap between the actual energy efficiency of components through comprehensive consideration of components, vehicles and working conditions.

[0004] To achieve the purpose of the present invention, a first aspect of an embodiment of the present invention provides a method for evaluating energy efficiency of new energy vehicle components, comprising the following steps:

[0005] Step 1: During the cycle test, collect the power calculation parameters of the component to be tested and mark the cycle. At the end of each cycle, mark it as the first cycle. i The end of each cycle is marked as i The first cycle of the j Working condition section;

[0006] Step 2: According to the collected power calculation parameters, the measured power of the component to be tested in the working condition section is calculated at intervals of a preset time period, and the measured power of the component to be tested is divided by the rated power to obtain the load rate at equal time intervals;

[0007] Step 3: Based on the load rate, calculate the probability density distribution value of the operating condition section;

[0008] Step 4: Calculate the weight coefficient of each operating condition section according to the probability density distribution value;

[0009] Step 5: Calculate the average efficiency of the component under test in different operating conditions;

[0010] Step 6: Multiply the average efficiency of each operating section by the corresponding weight coefficient to obtain the i The comprehensive weighted efficiency of the cycle conditions.

[0011] Corresponding to the first aspect, the second aspect of this embodiment provides a new energy vehicle component energy efficiency evaluation system, comprising the following units: a parameter collection and marking unit, a load rate calculation unit, a probability density distribution value calculation unit, a weight coefficient calculation unit, an average efficiency calculation unit, and a comprehensive weighted efficiency calculation unit;

[0012] The parameter collection and marking unit is used to collect the power calculation parameters of the component to be tested during the cycle condition test and mark the cycle condition. At the end of each cycle condition, it is marked as the first i The end of each cycle is marked as i The first cycle of the j Working condition section;

[0013] The load rate calculation unit is used to calculate the measured power of the component to be tested in the working condition section according to the collected power calculation parameters at intervals of preset time periods, and divide the measured power of the component to be tested by the rated power to obtain the load rate at equal time intervals;

[0014] The probability density distribution value calculation unit is used to calculate the probability density distribution value of the operating condition section based on the load rate;

[0015] The weight coefficient calculation unit is used to calculate the weight coefficient of each operating condition section according to the probability density distribution value;

[0016] The average efficiency calculation unit is used to calculate the average efficiency of the component to be tested in different operating conditions;

[0017] The comprehensive weighted efficiency calculation unit is used to multiply the average efficiency of each operating section by the corresponding weight coefficient to obtain the first i The comprehensive weighted efficiency of the cycle conditions.

[0018] A third aspect of this embodiment provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the above-mentioned vehicle actual road test route planning method are implemented.

[0019] A fourth aspect of this embodiment provides a device including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned vehicle actual road test route planning method when executing the computer program.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The solution of the present invention comprehensively considers the impact of the number of cycles and operating conditions on the measured components, analyzes and evaluates the energy consumption of the measured components from the perspective of load rate (the percentage of average power relative to rated power), and has a smaller granularity and more dimensional evaluation angles than existing evaluation methods.

[0022] In addition, the built-in test condition characteristics can identify the operating condition section, which is conducive to more detailed research on the components under test. Moreover, more scientific and accurate analysis and evaluation results can be obtained through the study of the energy efficiency of components in different operating conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a method flow chart provided by an embodiment of the present invention;

[0024] Figure 2 The figure is a schematic diagram showing the principle of the present invention using a DC / DC converter as an application example. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Example 1

[0026] like Figure 1 As shown, this embodiment provides a method for evaluating energy efficiency of new energy vehicle components, including the following steps:

[0027] Step 1: During the cycle test, collect the power calculation parameters of the component to be tested and mark the cycle. At the end of each cycle, mark it as the first cycle. i The end of each cycle is marked as i The first cycle of the j Working condition section;

[0028] It should be noted that before step 1, the following steps are also included:

[0029] Find the energy inflow and output ends of the component to be tested, connect the wiring harness and sensor, and complete the test preparation. The wiring harness and sensor are used to collect the power calculation parameters of the component to be tested. The wiring harness and sensor are connected to the host computer through the data acquisition device.

[0030] In addition, the time, speed, characteristic parameters of the test conditions and key parameters such as the model and rated power of the component to be tested are input into the host computer. Preferably, the time, speed and characteristic parameters of the test conditions input refer to the test items taken from the corresponding national standards.

[0031] In a specific implementation, in order to improve the consistency between the actual test vehicle speed and the built-in operating condition vehicle speed, the time interval is reduced to 0.1 s by interpolation, thereby improving the accuracy of the operating condition segment determination.

[0032] In a specific embodiment, the power calculation parameters are mechanical energy parameters and / or electrical energy parameters, thermal energy parameters. Taking electrical energy parameters as an example, they include current and voltage. If voltage signals are collected, direct collection is generally selected. When collecting current, first ensure that the current clamp meter has been calibrated and is in working condition, the wiring harness is not damaged, and the power supply is normal. In the power-off state, the voltage and current channels of the component to be measured are set to zero in the data acquisition software, and the sensitivity, range, etc. are set.

[0033] Step 2: According to the collected power calculation parameters, the measured power of the component to be tested in the working condition section is calculated at intervals of a preset time period, and the measured power of the component to be tested is divided by the rated power to obtain the load rate at equal time intervals;

[0034] It should be noted that the preset time period may be 0.1s, or may be a time interval of 0.2s, 0.3s, etc.

[0035] Step 3: Based on the load rate, calculate the probability density distribution value of the operating condition segment. k The probability density distribution value of the working condition segment at the time , calculated using the following formula:

[0036]

[0037] Where: is the load factor at the kth moment, is the average load rate of the working condition section, is the standard deviation of load rate in the operating condition.

[0038] by For example, It is a set of load rates of the tested components with a time interval of 0.1s in a certain working condition.

[0039] The average load rate of the working condition section The calculation method is as follows:

[0040]

[0041] The standard deviation of load factor in the operating condition is The calculation method is as follows:

[0042]

[0043] Step 4: Calculate the weight coefficient at each moment according to the probability density distribution value , the specific method is as follows:

[0044]

[0045] Where: It is i Working condition j The sampling points included in each operating period.

[0046] It should be noted that the normal distribution function NORMDIST is used to calculate the probability density distribution value.

[0047] Step 5: Calculate the average efficiency of the component under test in different operating conditions;

[0048] Step 6: Multiply the average efficiency of each operating section by the corresponding weight coefficient to obtain the i The comprehensive weighted efficiency of a cycle condition.

[0049] Specifically, in step 6, i The comprehensive weighted efficiency of a cycle condition is calculated using the following formula:

[0050]

[0051] Where: For the i Cycle Condition j Comprehensive weighted efficiency of each operating section; For the i Cycle Condition j Weight coefficient of each operating condition section; For the i Cycle Condition j The average efficiency of the operating sections, m is the number of operating sections.

[0052] It should be noted that during the test, the system compares the time tolerance and speed tolerance of the actual vehicle based on the built-in test condition parameters. When the speed tolerance is greater than ±3km / h or the time tolerance is greater than ±1s, it is marked as a driving error and the duration of the error is recorded. When the cumulative duration of the error in a single cycle reaches 15s, the test is marked as terminated. Under the premise of the built-in test condition characteristic value, the number and frequency of cycle conditions determined by tolerance can ensure the accuracy of the test, especially for the end time point of the mileage test and the driver's operation during the test, which provides a better standardization method.

[0053] The following is an application example of DC / DC converter. Figure 2 As shown, the specific steps are:

[0054] Step 21: Collect the voltage and current at the energy input and output ends of the DC / DC converter, connect the sensor to the data acquisition device, and connect the data acquisition device to the host computer;

[0055] Step 22: Configure channel parameters in the host computer and set the acquisition channel to zero fifteen minutes after the vehicle is powered off. Select a reasonable filter order and select the bandwidth according to the signal frequency;

[0056] Step 23: Load the test condition information in csv file format in the host computer and load the rated power of the component to be tested.

[0057] Step 24: Determine the speed tolerance and time tolerance according to national standards, which are generally ±3km / h and ±1s respectively. Use the rule-based working condition segment recognition function to divide the number of cycles into n The test conditions are divided into m Each cycle uses i Indicates that each operating section is j express;

[0058] Step 25: Divide the measured power of the component to be tested by the rated power to obtain the load rate at equal time intervals. Use the maximum and minimum values ​​of the load rate of the component to be tested in the target operating section as the boundaries for weight coefficient allocation, and determine the weight based on different load rates. Calculate the mean and standard deviation, use the normal distribution function NORMDIST to calculate the return probability density distribution value corresponding to each data, and sum them up. Divide the return probability density distribution value corresponding to each data by the total to obtain the weight of each data. The load rate and weight of each operating section are shown in Table 1.

[0059] Table 1

[0060]

[0061] In step 25, the input power of the DC / DC converter is calculated by multiplying the measured values ​​of the voltage and current of the DC source, and the output power is calculated by multiplying the measured values ​​of the voltage and current at the load end.

[0062] Step 26: Calculate the average power of the component under test in each operating condition, as shown in the following formula.

[0063]

[0064] Where:

[0065] ——No. i Cycle No. jThe average efficiency of each operating section;

[0066] ——No. i Cycle No. j The output voltage of the DC / DC converter in each operating condition, in volts (V);

[0067] ——No. i Cycle No. j The output current of the DC / DC converter in each operating condition, in ampere (A);

[0068] ——No. i Cycle No. j The input voltage of the DC / DC converter in each operating condition, in volts (V);

[0069] ——No. i Cycle No. j The input current of the DC / DC converter in each operating period, in ampere (A).

[0070] Taking the CLTC-C operating condition as an example, the operating condition section is divided into three parts: low-speed section, medium-speed section and high-speed section, with a total duration of 1800s.

[0071] The average efficiency of the DC / DC converter in the three operating conditions is calculated to be 91.8%, 93.4% and 94.4% respectively.

[0072] Step 27: Multiply the average power of each operating section obtained in step 26 by the weighting coefficient obtained in step 25 to obtain the i The comprehensive weighted efficiency of each cycle condition is shown in the following formula.

[0073]

[0074] Where:

[0075] ——No. i Cycle No. j Comprehensive weighted efficiency of each operating section;

[0076] ——No. i Cycle No. j Weighting coefficient of each operating condition section.

[0077] ——No. i Cycle No. j Average efficiency of each operating section;

[0078] The calculation formula in step 7 obtains that the comprehensive weighted efficiency of the DC / DC converter in the first cycle is 93.6%. Example 2

[0079] Corresponding to the above method, the present embodiment provides a new energy vehicle component energy efficiency evaluation system, comprising the following units: a parameter collection and marking unit, a load rate calculation unit, a probability density distribution value calculation unit, a weight coefficient calculation unit, an average efficiency calculation unit, and a comprehensive weighted efficiency calculation unit;

[0080] The parameter collection and marking unit is used to collect the power calculation parameters of the component to be tested during the cycle condition test and mark the cycle condition. At the end of each cycle condition, it is marked as the first i The end of each cycle is marked as i The first cycle of the j Working condition section;

[0081] The load rate calculation unit is used to calculate the measured power of the component to be tested in the working condition section according to the collected power calculation parameters at intervals of preset time periods, and divide the measured power of the component to be tested by the rated power to obtain the load rate at equal time intervals;

[0082] The probability density distribution value calculation unit is used to calculate the probability density distribution value of the operating condition section based on the load rate;

[0083] The weight coefficient calculation unit is used to calculate the weight coefficient of each operating condition section according to the probability density distribution value;

[0084] The average efficiency calculation unit is used to calculate the average efficiency of the component to be tested in different operating conditions;

[0085] The comprehensive weighted efficiency calculation unit is used to multiply the average efficiency of each operating section by the corresponding weight coefficient to obtain the first i The comprehensive weighted efficiency of a cycle condition.

[0086] Among them, k The probability density distribution value of the working condition segment at the time , calculated using the following formula:

[0087]

[0088] Where: It is k The load factor at the moment, is the average load rate of the working condition section, is the standard deviation of load rate in the operating condition.

[0089] Among them, iThe comprehensive weighted efficiency of a cycle condition is calculated using the following formula:

[0090]

[0091] Where: For the i Cycle Condition j Comprehensive weighted efficiency of each operating section; For the i Cycle Condition j Weight coefficient of each operating condition section; For the i Cycle Condition j The average efficiency of each operating section, m is the number of operating sections.

[0092] Wherein, in step 1, the power calculation parameters are mechanical energy parameters and / or electrical energy parameters, thermal energy parameters.

[0093] It should be noted that other related solutions in this embodiment refer to the description of Embodiment 1 and will not be repeated here. Example 3

[0094] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned new energy vehicle component energy efficiency evaluation method are implemented.

[0095] For other contents of this embodiment, please refer to the contents of Embodiment 1 in detail, which will not be repeated here. Example 4

[0096] This embodiment provides a device including a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above-mentioned new energy vehicle component energy efficiency evaluation method when executing the computer program.

[0097] For other contents of this embodiment, please refer to the contents of Embodiment 1 in detail, which will not be repeated here.

[0098] The optional implementation modes of the embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation modes. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical scheme of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.

Claims

1. A method for evaluating energy efficiency of new energy vehicle components, characterized in that: The steps include: Step 1: During the cycle test, collect the power calculation parameters of the component to be tested and mark the cycle. At the end of each cycle, mark it as the first cycle. i The end of each cycle is marked as i The first cycle of the j Working condition section; Step 2: According to the collected power calculation parameters, the measured power of the component to be tested in the working condition section is calculated at intervals of a preset time period, and the measured power of the component to be tested is divided by the rated power to obtain the load rate at equal time intervals; Step 3: Based on the load rate, calculate the probability density distribution value of the operating condition section; Among them, in step 3, k The probability density distribution value of the working condition segment at the time , calculated using the following formula: ； Where: It is k The load factor at the moment, is the average load rate of the working condition section, is the standard deviation of load factor in the operating condition; Step 4: Calculate the weight coefficient of each operating condition section according to the probability density distribution value; The specific method is as follows: ； ； Where: It is i Working condition j The sampling points included in each operating section; For the i Cycle Condition j Weight coefficient of each operating condition section; is the weight coefficient for each moment; Step 5: Calculate the average efficiency of the component under test in different operating conditions; Step 6: Multiply the average efficiency of each operating section by the corresponding weight coefficient to obtain the i The comprehensive weighted efficiency of a cycle condition.

2. A method for evaluating energy efficiency of new energy vehicle components according to claim 1, characterized in that: In step 6, i The comprehensive weighted efficiency of a cycle condition is calculated using the following formula: ； Where: For the i Cycle Condition j Comprehensive weighted efficiency of each operating section; For the i Cycle Condition j Weight coefficient of each operating condition section; For the i Cycle Condition j The average efficiency of the operating sections, m is the number of operating sections.

3. A method for evaluating energy efficiency of new energy vehicle components according to claim 1, characterized in that: In step 1, the power calculation parameters are mechanical energy parameters and / or electrical energy parameters, thermal energy parameters.

4. A new energy vehicle component energy efficiency evaluation system, characterized in that: It includes the following units: parameter collection and marking unit, load rate calculation unit, probability density distribution value calculation unit, weight coefficient calculation unit, average efficiency calculation unit and comprehensive weighted efficiency calculation unit; The parameter collection and marking unit is used to collect the power calculation parameters of the component to be tested during the cycle condition test and mark the cycle condition. At the end of each cycle condition, it is marked as the first i The end of each cycle is marked as i The first cycle of the j Working condition section; The load rate calculation unit is used to calculate the measured power of the component to be tested in the working condition section according to the collected power calculation parameters at intervals of preset time periods, and divide the measured power of the component to be tested by the rated power to obtain the load rate at equal time intervals; The probability density distribution value calculation unit is used to calculate the probability density distribution value of the operating condition section based on the load rate; wherein k The probability density distribution value of the working condition segment at the time , calculated using the following formula: ； Where: It is k The load factor at the moment, is the average load rate of the working condition section, is the standard deviation of load factor in the operating condition; The weight coefficient calculation unit is used to calculate the weight coefficient of each operating condition section according to the probability density distribution value; The specific method is as follows: ； ； Where: It is i Working condition j The sampling points included in each operating section; For the i Cycle Condition j Weight coefficient of each operating condition section; is the weight coefficient for each moment; The average efficiency calculation unit is used to calculate the average efficiency of the component to be tested in different operating conditions; The comprehensive weighted efficiency calculation unit is used to multiply the average efficiency of each operating section by the corresponding weight coefficient to obtain the first i The comprehensive weighted efficiency of the cycle conditions.

5. A new energy vehicle component energy efficiency evaluation system according to claim 4, characterized in that: No. i The comprehensive weighted efficiency of a cycle condition is calculated using the following formula: ； Where: For the i Cycle Condition j Comprehensive weighted efficiency of each operating section; For the i Cycle Condition j Weight coefficient of each operating condition section; For the i Cycle Condition j The average efficiency of each operating section, m is the number of operating sections.

6. A new energy vehicle component energy efficiency evaluation system according to claim 4, characterized in that: The power calculation parameters are mechanical energy parameters and / or electrical energy parameters, thermal energy parameters.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the new energy vehicle component energy efficiency evaluation method as described in any one of claims 1 to 3 are implemented.

8. A device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, the steps of the new energy vehicle component energy efficiency evaluation method as described in any one of claims 1 to 3 are implemented.

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