Automatic test method for rated power of DC / DC converter of new energy automobile

Abstract

The invention discloses an automatic test method for rated power of a DC / DC converter of a new energy automobile, which mainly aims at finding and adjusting the condition that the actual output power of the DC / DC converter is higher than a rated value in time and avoiding the risks of fuse fusing, line overheating, low-voltage electric equipment burning, even fire and the like caused by exceeding the bearing limit of a low-voltage system component. Specifically, the method comprises the steps of firstly deploying a power test system and performing line connection, setting test parameters after deployment is completed, starting a test and collecting test data within a preset test duration; in the test process, when the output power of the DC / DC converter exceeds the power control upper and lower limit values, the current of the DC electronic load is automatically adjusted, so that the output power of the DC / DC converter returns to the control range. According to the invention, the test value of the rated power of the DC / DC converter can be accurately obtained at one time, the test cost is greatly reduced, the safety is improved, and the consistency and reliability of the test result are effectively ensured.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle testing technology, and in particular to an automated test method for the rated power of a DC / DC converter in a new energy vehicle. Background Technology

[0002] The DC / DC converter in new energy vehicles is a key electronic component. It serves as a bridge between high-voltage and low-voltage systems, and its main function is to convert high voltage to low voltage, ultimately achieving voltage conversion and energy distribution.

[0003] According to industry regulations, the continuous operating time of a DC / DC converter at its rated power must not be less than 2 hours. In actual testing of the rated power of DC / DC converters in new energy vehicles, the power of electrical components such as fans and water pumps in the test vehicle may change at any time. Therefore, test personnel need to visually monitor the rated power of the DC / DC converter constantly. If the power exceeds the allowable deviation range, they must promptly control the DC electronic load to maintain it at the rated power output. However, in actual testing, test personnel not only need to monitor the rated power changes, but also need to constantly monitor the vehicle status, the input and output current and voltage of the DC / DC converter, the current and voltage of the battery, and the vehicle's CAN signals. Because test personnel inevitably experience inattention, equipment operation errors, and focusing on too many things at once, the rated power may sometimes exceed the allowable deviation range, leading to test failure or even safety accidents. The main reasons for this are as follows:

[0004] (1) If the actual output power of the DC / DC converter is not found to be higher than the rated value during the test, it may exceed the tolerance limit of the low-voltage system components, causing the fuse to blow, the line to overheat, or even burn out the low-voltage electrical equipment and cause a fire.

[0005] (2) If the actual output power of the DC / DC converter is not found to be lower than the rated value in time during the test, it may cause insufficient charging of the low-voltage battery, affecting the normal operation of the vehicle electrical appliances. In severe cases, it may cause the vehicle to lose high voltage, thus invalidating the test.

[0006] (3) If the DC electronic load is not adjusted in time after the output power of the DC / DC converter deviates from the rated value, the test results will not meet the requirements of GB / T 24347-2021 standard, resulting in the test being invalid;

[0007] (4) Manual operation speed is limited by physiological limits and cannot maintain high speed for a long time. Moreover, the operation accuracy is easily affected by fatigue, emotions and experience. There are unavoidable operation errors by manually adjusting the DC electronic load, resulting in large test errors and reduced test accuracy. Summary of the Invention

[0008] In view of the above, the present invention aims to provide an automated testing method for the rated power of DC / DC converters in new energy vehicles, so as to solve the aforementioned technical problems.

[0009] The technical solution adopted in this invention is as follows:

[0010] This invention provides an automated test method for the rated power of DC / DC converters in new energy vehicles, including:

[0011] Deploy a power test system and make line connections. The test system includes at least: a DC / DC converter, a battery, a DC electronic load with a built-in voltage sensor, a CAN network communication device, a current clamp power supply module, a current clamp, and a host computer.

[0012] After the deployment of the test system is completed, the test parameters are set; wherein, the test parameters include at least: upper limit value of power control and lower limit value of power control;

[0013] After the parameters are set, start the experiment and collect test data within the preset test duration;

[0014] During the test, when the output power of the DC / DC converter is higher than the upper limit of power control or lower than the lower limit of power control, the current of the DC electronic load is automatically adjusted so that the output power of the DC / DC converter returns to the control range.

[0015] In at least one possible implementation, the deployment of the power testing system and the line connection include:

[0016] The positive and negative terminals of the DC / DC converter are connected to the corresponding batteries, and the current output by the DC / DC converter is transmitted to the current clamp power supply module by the current clamp, and then input to the CAN network communication device as an analog voltage signal.

[0017] The positive and negative terminals of the DC electronic load are connected to the corresponding batteries. The voltage of the batteries is conducted to the DC electronic load and input to the CAN network communication device in the form of CAN signals.

[0018] CAN network communication devices exchange data with the host computer.

[0019] In at least one of the possible implementations, the output power of the DC / DC converter is obtained by multiplying the voltage across the battery terminals and the output current of the DC / DC converter.

[0020] In at least one of the possible implementations, setting the test parameters includes: setting an upper limit value for power control and a lower limit value for power control based on the preset rated power value of the DC / DC converter.

[0021] In at least one possible implementation, setting the test parameters further includes setting load parameters: initial load value, load reduction value, and load increase value.

[0022] In at least one possible implementation, the automated testing method includes triggering an audible and visual alarm via a host computer when the output power of the DC / DC converter is higher than the upper limit of power control or lower than the lower limit of power control.

[0023] Compared with existing technologies, the main design concept of this invention lies in timely detection and adjustment of situations where the actual output power of a DC / DC converter exceeds its rated value, thus avoiding risks such as fuse blowouts, overheating of circuits, burnout of low-voltage electrical equipment, or even fires caused by exceeding the limits of low-voltage system components. Specifically, a power testing system is first deployed and the wiring is connected. After the deployment of the testing system is completed, test parameters are set. After the parameters are set, the test is started, and test data is collected within the preset test duration. During the test, when the output power of the DC / DC converter exceeds the upper limit of power control or falls below the lower limit of power control, the current of the DC electronic load is automatically adjusted to bring the output power of the DC / DC converter back to the control range. This invention can accurately obtain the test value of the rated power of the DC / DC converter in one go, significantly reducing test costs and improving safety, effectively ensuring the consistency and reliability of test results.

[0024] In summary, the present invention offers at least the following advantages:

[0025] First, it ensures the continuity of testing: it can quickly detect and adjust the problem that the actual output power of the DC / DC converter is lower than the rated value, prevent the low-voltage battery from being insufficiently charged and affecting the operation of the vehicle's electrical appliances, avoid the test being interrupted and invalidated due to the vehicle being subjected to high voltage, and save test costs.

[0026] Second, ensure compliance with standards: When the output power of the DC / DC converter deviates from the rated value, adjust the DC electronic load in a timely manner to ensure that the test results meet industry standards, avoid invalidation of the test due to non-compliance, and reduce waste of test resources.

[0027] Third, improve test accuracy: It replaces the manual adjustment of DC electronic load, effectively avoids human operation error, reduces the overall test error, and improves the accuracy and reliability of DC / DC converter rated power test data.

[0028] Fourth, high versatility: This invention is applicable to rated power testing of DC / DC converters in most existing new energy vehicles. Attached Figure Description

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described below with reference to the accompanying drawings, wherein:

[0030] Figure 1 A schematic diagram of an automated test method for rated power of DC / DC converters in new energy vehicles provided in an embodiment of the present invention;

[0031] Figure 2 This is a schematic diagram of the architecture of a DC / DC converter rated power test system provided in an embodiment of the present invention. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0033] This invention proposes an embodiment of an automated test method for the rated power of DC / DC converters in new energy vehicles, such as... Figure 1 and Figure 2 As shown, the test method includes:

[0034] Step S1: Deploy the power test system and connect the lines;

[0035] The data that needs to be collected by the rated power test system for the DC / DC converter of new energy vehicles mainly includes the current signal output by the DC / DC converter and the voltage signal of the battery. Figure 2 As shown, the test system may specifically include: a DC / DC converter for a new energy vehicle, a battery, a DC electronic load with a built-in voltage sensor, a CAN network communication device, a current clamp power supply module, a current clamp, and a host computer; To elaborate on this system:

[0036] (1) The current output by the DC / DC converter is transmitted to the current clamp power supply module by the current clamp, and after internal circuit conversion and calculation, it is input to the CAN network communication device through an analog voltage signal. Specifically, the positive output current of the DC / DC converter is converted into a voltage signal by the current sensor and transmitted to the current clamp power supply module. The current clamp power supply module transmits the converted voltage signal to the VN1640A device through the DB9 wiring harness.

[0037] (2) The battery voltage is transmitted to the DC electronic load by a voltage sensor and input to the CAN network communication device in the form of a CAN signal. Specifically, the positive and negative wiring harnesses of the DC electronic load are connected in parallel with the positive and negative terminals of the battery, and the CAN signal is transmitted to the VN1640A device through the DB9 wiring harness. It should be noted that the above-mentioned battery voltage acquisition is based on the fact that the power consumption of the vehicle's low-voltage electrical appliances starts from the battery terminal, not the output terminal of the DC / DC converter (losses have been considered in the rated power test of the DC / DC converter).

[0038] (3) The VN1640A device interacts with the host computer via a USB cable. In some preferred embodiments of the present invention, the CAN network communication device mentioned above is preferably Vector's VN1640A. This CAN network communication device has an independent programming development platform. It can use the CAPL programming language to write automated testing software for the rated power of the DC / DC converter of new energy vehicles in the CANoe software of the host computer. The VN1640A device is used to read and modify the DC electronic load current, and finally realize the control of the output current of the DC / DC converter. In addition, the CAN network communication device can establish communication with Matlab's built-in CANoe communication toolkit to perform operations such as CAN signal baud rate, CAN channel opening and closing, and CAN signal reading and sending. The CAN network communication device is connected to the host computer via a USB port. The CAN signal output end is four DB9 physical ports. The 7th pin of the four DB9 interfaces is CAN_H, and the 2nd pin is CAN_L. All four physical ports can be used for testing, but the corresponding ports must be opened on the host computer.

[0039] (4) A DC electronic load is an electronic test instrument used to simulate real load conditions. It absorbs DC power and dissipates, stores, or feeds it back to the power grid to test the performance of devices such as power supplies and batteries. Its core function is to provide constant current (CC), constant voltage (CV), constant resistance (CR), or constant power (CP) modes through programmable control to simulate diverse load requirements.

[0040] (5) In this embodiment of the invention, a host computer and a VN1640A device are used to read and send CAN signals. Combined with a DC electronic load and a current clamp, the rated power output of the DC / DC converter is precisely controlled by controlling the upper and lower limits of the input power.

[0041] Continuing from the previous text, regarding the deployment of the power test system and the connection of the lines, in actual operation it can be manifested as follows:

[0042] Connect pins 7 and 2 of the DB9 interface of one of the CAN signal output terminals of the CAN network communication device to the CAN_H and CAN_L signal terminals of the DC electronic load, respectively; connect the positive and negative signal output terminals of the current clamp power supply module to the I / O analog input port of the CAN network communication device.

[0043] The CAN signal input terminal of the CAN network communication device is connected to the host computer via a USB port. After the CAN network communication device is connected to the host computer, the VN1600_Series_Driver driver will be started automatically. If the driver successfully interacts with the CAN network communication device, the Status indicator light on the CAN network communication device will be solid green. If the startup fails, the Status indicator light will be solid red. Try unplugging and plugging the USB port again or connecting it to another USB port until the Status indicator light is solid green.

[0044] Next, the CAN communication baud rate and CAN signal output port are configured using the CANoe 12.0 software on the host computer. The rated power automated test software interface programmed by CAPL is used to observe the values ​​of current, battery voltage and power output by the DC / DC converter.

[0045] Furthermore, the positive and negative terminals of the DC electronic load are connected one-to-one with the positive and negative terminals of the battery. The host computer automatically controls the DC electronic load to absorb current, thereby achieving the purpose of controlling the current at the output terminal of the DC / DC converter and ultimately realizing the automatic adjustment of the output power of the DC / DC converter.

[0046] Step S2: After completing the deployment of the test system, set the test parameters; wherein the test parameters include at least: power control upper limit value and power control lower limit value;

[0047] Specifically, the host computer can set the upper limit of power control to 98% × P based on the rated power design value (and knowing that the conversion efficiency of the DC / DC converter to the battery is 3% to 15%). 额定 And the power control lower limit is set to 96%×P 额定 ;

[0048] In addition, the test parameters also include: tensile load parameters, specifically, the initial tensile load value can be set to 90% × P. 额定 The load reduction value is set to the first gradient value of 0.2A (where the load rate is the set value per second × 10, and can be modified), and the load increase value is set to the second gradient value of 0.3A.

[0049] Step S3: After the parameters are set, start the experiment and collect the test data within the preset test duration (e.g., 2 hours);

[0050] In actual operation, you can first click the "Load" button in the host computer software interface, and after the power stabilizes to the target value, click the "Record" button to start data acquisition, which includes electrical signal data such as battery voltage, DC / DC converter output current, and DC electronic load current.

[0051] Step S4: During the test, when the output power of the vehicle's DC / DC converter exceeds the upper limit of power control or falls below the lower limit of power control, the current of the DC electronic load is automatically adjusted (lower if exceeding the upper limit, higher if below the lower limit) to bring the output power of the DC / DC converter back within the control range. Alternatively, an audible and visual alarm can be triggered via a host computer, for example, but not limited to, through the host computer's computer display interface. The output power value of the vehicle's DC / DC converter is obtained by multiplying the voltage across the battery terminals by the output current of the DC / DC converter.

[0052] In summary, the main design concept of this invention is to promptly detect and adjust situations where the actual output power of a DC / DC converter exceeds its rated value, thus avoiding risks such as fuse blowouts, overheating of circuits, burnout of low-voltage electrical equipment, or even fires caused by exceeding the limits of low-voltage system components. Specifically, a power testing system is first deployed and the wiring is connected. After the deployment of the testing system is completed, test parameters are set. After the parameters are set, the test is started, and test data is collected within the preset test duration. During the test, when the output power of the DC / DC converter exceeds the upper limit of power control or falls below the lower limit of power control, the current of the DC electronic load is automatically adjusted to bring the output power of the DC / DC converter back to the control range. This invention can accurately obtain the test value of the rated power of the DC / DC converter in one go, significantly reducing test costs and improving safety, effectively ensuring the consistency and reliability of test results.

[0053] In this invention, when directional terms are mentioned, they are relative concepts based on the embodiments. Furthermore, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, A and B simultaneously, or B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, and c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.

[0054] The above description of the structure, features, and effects of the present invention is based on the embodiments shown in the figures. However, the above are only preferred embodiments of the present invention. It should be noted that the technical features involved in the above embodiments and their preferred methods can be reasonably combined and matched by those skilled in the art to form a variety of equivalent solutions without departing from or changing the design concept and technical effects of the present invention. Therefore, the present invention is not limited to the scope of implementation shown in the figures. Any changes made in accordance with the concept of the present invention, or modifications to equivalent embodiments, that do not exceed the spirit covered by the specification and figures, should be within the protection scope of the present invention.

Claims

1. A new energy vehicle DC / DC converter rated power automatic test method, characterized in that, The application relates to an automatic test method for a DC / DC converter. The test system comprises a DC / DC converter, a battery, a direct-current electronic load with a built-in voltage sensor, CAN network communication equipment, a current clamp power supply module, a current clamp and a host computer. After the test system is deployed, test parameters are set, wherein the test parameters at least include a power control upper limit value and a power control lower limit value. After the parameters are set, the test is started, and test data are collected within a preset test duration. During the test, when the output power of the DC / DC converter is higher than the power control upper limit value or lower than the power control lower limit value, the current of the direct-current electronic load is automatically adjusted, so that the output power of the DC / DC converter returns to the control range.

2. The method according to claim 1, wherein, The DC / DC converter is connected to the battery, and the current output by the DC / DC converter is transmitted to the current clamp power supply module by the current clamp, and is input to the CAN network communication equipment in the form of an analog voltage signal. The positive and negative poles of the direct-current electronic load are connected to the battery, and the voltage of the battery is transmitted to the direct-current electronic load and input to the CAN network communication equipment in the form of a CAN signal. The CAN network communication equipment and the host computer exchange data. The output power value of the DC / DC converter is obtained by multiplying the voltage between the battery and the output current of the DC / DC converter.

3. The method according to claim 1, wherein, The test parameters are set according to the preset rated power value of the DC / DC converter.

4. The method of claim 1, wherein the method further comprises: The test parameters also include setting pull load parameters, such as a pull load initial value, a pull load reduction value and a pull load increase value.

5. The method according to claim 4, wherein, When the output power of the DC / DC converter is higher than the power control upper limit value or lower than the power control lower limit value, the host computer triggers an audible and light alarm.

6. The method according to any one of claims 1-5, wherein, ​

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