Vehicle low-voltage load energy flow test system and test method

Abstract

The invention relates to a vehicle low-voltage load energy flow test system and test method. The vehicle low-voltage load energy flow test system comprises an acquisition controller; the diverter A, the diverter B and the switch A are connected in series and are connected to the vehicle-mounted fuse box; the switch B is connected with the shunt B in parallel; the analog-to-digital converters A and B are respectively connected with the diverters A and B in parallel and are respectively used for acquiring voltage values of the diverters A and B and sending the voltage values to the acquisition controller; the analog-to-digital converter C is used for acquiring the voltage value of the vehicle-mounted storage battery and sending the voltage value to the acquisition controller; the temperature sensors A, B and C are respectively used for acquiring the temperature values of the diverters A and B and the wiring terminals A and B; the analog-to-digital converters D, E and F are respectively connected to the temperature sensors A, B and C; wherein the acquisition controller calculates the energy flow of the vehicle-mounted low-voltage load according to the received voltage value. According to the invention, the energy flow of the vehicle low-voltage load can be effectively obtained, and the test efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle testing, and in particular to a vehicle low-voltage load energy flow testing system and a testing method. Background Art

[0002] As cars enter thousands of households, traditional fuel vehicles have caused many problems, while new energy vehicles have attracted attention but have range anxiety. As a result, reducing energy consumption has become a consensus in the automotive industry, and low-voltage load energy consumption has become a research focus, with energy flow testing technology gaining favor.

[0003] There are many methods for testing the energy flow of low-voltage loads in vehicles: one is to use vehicle sensors and the CAN communication network to read messages, but the on-board CAN messages are incomplete, confidential DBC files need to be parsed, and the vehicle needs to be unlocked, which makes implementation difficult; the second is to disassemble the vehicle analysis architecture and then connect the sensor measurement, which has high manpower, material and time costs, is easy to damage the vehicle, and is difficult to operate; the third is to use the fuse box for indirect measurement. Although it is easy to operate and takes a short preparation time, the shunt will divide the voltage, affecting the accuracy and energy consumption calculation, and it is difficult to deal with complex loads. Summary of the invention

[0004] In view of the above problems in the prior art, the present invention proposes a vehicle low-voltage load energy flow testing system and testing method, which can effectively obtain the energy flow of the vehicle low-voltage load and improve the testing efficiency.

[0005] Specifically, the present invention proposes a vehicle low-voltage load energy flow test system, wherein the vehicle includes a vehicle-mounted battery, a vehicle-mounted fuse box and a vehicle-mounted low-voltage load connected in series, and the vehicle low-voltage load energy flow test system includes:

[0006] Acquisition controller;

[0007] Shunt A, shunt B and switch A are connected in series and connected to terminals A and B of the vehicle fuse box;

[0008] A switch B is connected in parallel with the shunt B;

[0009] Analog-to-digital converter A and analog-to-digital converter B are respectively connected in parallel with the shunt A and the shunt B, and the analog-to-digital converter A and the analog-to-digital converter B are used to obtain the voltage values ​​of the shunt A and the shunt B and send them to the acquisition controller;

[0010] An analog-to-digital converter C is used to obtain the voltage value of the vehicle-mounted battery and send it to the acquisition controller;

[0011] The temperature sensor A, the temperature sensor B and the temperature sensor C are used to obtain the temperature values ​​of the shunt A, the shunt B and the connection terminals A and B respectively;

[0012] Analog-to-digital converter D, analog-to-digital converter E and analog-to-digital converter F are respectively connected to the temperature sensor A, temperature sensor B and temperature sensor C, and the temperature values ​​obtained by the temperature sensor A, temperature sensor B and temperature sensor C are sent to the acquisition controller;

[0013] The acquisition controller calculates the energy flow of the vehicle-mounted low-voltage load according to the received voltage value.

[0014] According to an embodiment of the present invention, the shunt A is a precision resistor at the milliohm level, and the shunt B is a precision resistor at the ohm level.

[0015] According to one embodiment of the present invention, the vehicle low-voltage load energy flow test system also includes a resistance measurement module A and a resistance measurement module B, which are respectively connected in parallel with the shunt A and the shunt B, and the resistance measurement module A and the resistance measurement module B are used to obtain the resistance values ​​of the shunt A and the shunt B and send them to the acquisition controller.

[0016] According to one embodiment of the present invention, the vehicle low-voltage load energy flow test system further includes a timer connected to the acquisition controller.

[0017] According to one embodiment of the present invention, the vehicle low-voltage load energy flow test system also includes a memory, a display device and an output interface, the memory is used to store the calculation results of the acquisition controller and the received original acquisition data, the measurement personnel interact with the acquisition controller through the display device, and the acquisition controller is connected to external devices through the output interface and outputs the calculation results and original acquisition data.

[0018] According to one embodiment of the present invention, the acquisition controller includes a receiving unit, a computing unit and a control unit, the receiving unit is used to receive voltage values ​​and temperature values, the computing unit is used to calculate the energy flow of the vehicle-mounted low-voltage load based on the received voltage value, and the control unit is used to control the opening and closing of the switch A and the switch B.

[0019] The present invention also provides a vehicle low-voltage load energy flow test method, which is applicable to the above-mentioned vehicle low-voltage load energy flow test system, and the vehicle low-voltage load energy flow test method comprises:

[0020] S1, unloading the original fuse in the vehicle fuse box;

[0021] S2, connect the shunt A, shunt B and switch A of the test system in series, and connect them to terminals A and B of the vehicle fuse box; connect the analog-to-digital converter C to the vehicle battery;

[0022] S3, close the switch A and switch B, if the real-time current I is greater than or equal to the threshold current I θ , then it is determined that the real-time current I measurement is valid;

[0023] If the real-time current I is less than the threshold current I θ , then disconnect the switch B, if the updated real-time current I is less than the threshold current I θ , then it is determined that the real-time current I measurement is valid;

[0024] S4, calculating the energy flow of the low-voltage load of the vehicle.

[0025] According to one embodiment of the present invention, in step S4, if the switch A and the switch B are closed and the real-time current I measurement is valid, the difference between the real-time voltage U3 of the vehicle-mounted battery obtained by the analog-to-digital converter C and the real-time voltage value U1 obtained by the analog-to-digital converter A is used as the real-time voltage U of the vehicle-mounted low-voltage load; the real-time power P of the vehicle-mounted low-voltage load is calculated based on the real-time voltage U and the real-time current I, and the energy consumption E of the vehicle-mounted low-voltage load is obtained by integration;

[0026] If the switch A is closed, the switch B is open, and the real-time current I measurement is valid, the real-time voltage U3 of the vehicle battery obtained by the analog-to-digital converter C, the real-time voltage value U1 obtained by the analog-to-digital converter A and the real-time voltage value U2 obtained by the analog-to-digital converter B are used to calculate the real-time voltage U of the vehicle low-voltage load; the real-time power P of the vehicle low-voltage load is calculated based on the real-time voltage U and the real-time current I, and the energy consumption E of the vehicle low-voltage load is obtained by integration.

[0027] According to one embodiment of the present invention, in step S3, if the real-time current I exceeds the fuse current Imax, the switch A is disconnected; if any one of the real-time temperature T1 of the shunt A, the real-time temperature T2 of the shunt B and the temperature T3 of the terminals A and B obtained by the temperature sensor A, the temperature sensor B and the temperature sensor C is less than the temperature threshold Tmin or greater than the temperature threshold Tmax, the switch A is disconnected.

[0028] According to an embodiment of the present invention, after step S2 and before executing step S3, the resistance R1 of the shunt A is obtained by the resistance measurement module A, and the resistance R2 of the shunt B is obtained by the resistance measurement module B.

[0029] The present invention provides a vehicle low-voltage load energy flow test system and test method. A shunt A, a shunt B and a switch A are connected in series and connected to terminals A and B of the vehicle-mounted fuse box. The energy flow of the vehicle-mounted low-voltage load can be detected. The overall operation is convenient, the energy flow of the vehicle low-voltage load can be effectively obtained, and the test efficiency is improved.

[0030] It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this application. The accompanying drawings illustrate embodiments of the present invention and together with the description serve to explain the principle of the present invention.

[0032] In the attached figure:

[0033] Figure 1 A schematic structural diagram of a vehicle low-voltage load energy flow test system according to an embodiment of the present invention is shown.

[0034] Figure 2 A flowchart of a vehicle low-voltage load energy flow testing method according to an embodiment of the present invention is shown.

[0035] The above drawings include the following reference numerals:

[0036] Test system 100

[0037] Acquisition Controller 101

[0038] Shunt A 102

[0039] Shunt B 103

[0040] Switch A 104

[0041] Switch B 105

[0042] Analog to Digital Converter A 106

[0043] Analog-to-digital converter B 107

[0044] Analog to Digital Converter C 108

[0045] Temperature sensor A 109

[0046] Temperature sensor B 110

[0047] Temperature sensor C 111

[0048] Analog to digital converter D 112

[0049] Analog-to-digital converter E 113

[0050] Analog-to-digital converter F 114

[0051] Resistance measurement module A 115

[0052] Resistance measurement module B 116

[0053] Timer 117

[0054] Memory 118

[0055] Display device 119

[0056] Output interface 120

[0057] Buzzer 121

[0058] Car battery 201

[0059] Car fuse box 202

[0060] On-board low voltage load 203 DETAILED DESCRIPTION

[0061] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0062] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0063] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0064] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0065] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0066] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0067] In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and cannot be understood as limiting the scope of protection of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.

[0068] Figure 1 The structural schematic diagram of a vehicle low-voltage load energy flow test system according to an embodiment of the present invention is shown. As shown in the figure, the present invention provides a vehicle low-voltage load energy flow test system 100. The vehicle using the test system 100 includes a vehicle-mounted battery 201, a vehicle-mounted fuse box 202 and a vehicle-mounted low-voltage load 203 connected in series. Among them, the vehicle-mounted battery 201 is a ternary battery, a lithium iron phosphate battery, etc., and the working voltage is generally 12V, which is used to power various low-voltage electrical appliances on the vehicle. The vehicle-mounted fuse box 202 is a collection of fuse plug ports of various types and styles, which are used to plug fuses to protect the safety of the low-voltage load circuit. The vehicle-mounted low-voltage load 203 is various low-voltage electrical appliances on the vehicle, such as electronic fans, blowers, motor water pumps and battery water pumps, etc., which are used to realize certain functions of the car. The test system 100 includes:

[0069] The acquisition controller 101 is mainly responsible for data processing and control tasks;

[0070] The shunt A 102, the shunt B 103 and the switch A 104 are connected in series in sequence and connected to the terminals A and B of the vehicle fuse box 202;

[0071] The switch B 105 is connected in parallel with the shunt B 103, and the switch B 105 is used to selectively connect to the shunt B 103; the switch A 104 and the switch B 105 can be electromagnetic relays, MOS tubes, etc., connected to the acquisition controller 101, and the switch A 104 and the switch B 105 are controlled by the acquisition controller 101;

[0072] Analog-to-digital converter A 106 and analog-to-digital converter B 107 are connected in parallel with shunt A 102 and shunt B 103, respectively. Analog-to-digital converter A 106 and analog-to-digital converter B 107 integrate voltage detection and analog-to-digital conversion functions, and are used to obtain voltage values ​​of shunt A 102 and shunt B 103 and send them to acquisition controller 101;

[0073] The analog-to-digital converter C 108 is used to obtain the voltage value of the vehicle battery 201 and send it to the acquisition controller 101. The analog-to-digital converter C 108 is connected to the terminals C and D of the vehicle battery 201, that is, the positive and negative terminals;

[0074] The temperature sensor A 109, the temperature sensor B 110 and the temperature sensor C 111 are used to obtain the temperature values ​​of the shunt A 102, the shunt B 103 and the connection terminals A and B respectively;

[0075] The analog-to-digital converter D 112, the analog-to-digital converter E 113 and the analog-to-digital converter F 114 are respectively connected to the temperature sensor A 109, the temperature sensor B 110 and the temperature sensor C 111, and the temperature values ​​acquired by the temperature sensor A 109, the temperature sensor B 110 and the temperature sensor C 111 are sent to the acquisition controller 101 after analog-to-digital conversion;

[0076] The acquisition controller 101 calculates the energy flow of the vehicle-mounted low-voltage load 203 according to the received voltage value.

[0077] In some examples, shunt A is a precision resistor at the milliohm level, such as 1mΩ. Shunt A is connected in series in the measurement loop to form a voltage divider circuit, and cooperates with analog-to-digital converter A 106 to achieve current measurement of the vehicle-mounted low-voltage loop. Due to its extremely small resistance value, it can have extremely high sensitivity to tiny current changes, thereby achieving high-precision current measurement. Shunt B is a precision resistor at the ohm level, such as 1Ω. Shunt B is connected in series in the measurement loop to form a voltage divider circuit, and cooperates with analog-to-digital converter B 107 to achieve current measurement of the vehicle-mounted low-voltage loop. This setting of a larger resistance value is suitable for measurement of a relatively larger current range. Since the loop current of the vehicle-mounted low-voltage load 203 under different working conditions has obvious differences, including micro-leakage current in sleep mode, surge and impact current at startup, and working current at different gears during operation. Through the mutual cooperation of shunt A and shunt B, the effective range and dynamics are improved, which can meet the high-precision measurement of the loop current of the vehicle-mounted low-voltage load 203 under all working conditions.

[0078] In some examples, the vehicle low-voltage load energy flow test system 100 further includes a resistance measurement module A 115 and a resistance measurement module B 116. The resistance measurement module A 115 and the resistance measurement module B 116 are connected in parallel to the shunt A 102 and the shunt B 103, respectively, and the resistance measurement module A 115 and the resistance measurement module B 116 are used to obtain the resistance values ​​of the shunt A 102 and the shunt B 103 and send them to the acquisition controller 101. Although the resistance value of the shunt resistor is usually considered to be fixed during the test process, in actual use, if the vehicle is in an extreme environment, the shunt resistor is used for a long time and at a high frequency, and in other cases, the resistance value of the shunt will inevitably change, and real-time calibration cannot be achieved, resulting in a significant reduction in the accuracy and credibility of the measurement data. By using the resistance measurement module A 115 and the resistance measurement module B 116, the resistance values ​​of the shunt A 102 and the shunt B 103 can be obtained in real time before the test, and the acquisition controller 101 can more accurately calculate the energy flow of the vehicle-mounted low-voltage load 203 based on the resistance value, and comprehensively improve the monitoring and control capabilities of the vehicle low-voltage load energy consumption. Preferably, the resistance measurement module A 115 and the resistance measurement module B 116 can be circuit modules designed based on RC oscillation electrical method, bridge method, constant current source method, etc., and the acquisition controller 101 controls the start and stop.

[0079] In some examples, the vehicle low-voltage load energy flow test system 100 also includes a timer 117, which is connected to the acquisition controller 101. The timer 117 is equivalent to setting the clock of the entire system, and the timer 117 will transmit the time to the acquisition controller 101 and the analog-to-digital converter. The analog-to-digital converter A 106, the analog-to-digital converter B 107 and the analog-to-digital converter C 108 will convert the analog voltage value into a digital value based on the set sampling frequency and the time of the timer 117, and transmit it to the acquisition controller 101. Preferably, the timer 117 is a high-precision crystal oscillator, which is used to generate information such as seconds, minutes, hours, and days.

[0080] In some examples, the vehicle low-voltage load energy flow test system 100 also includes a memory 118, a display device 119 and an output interface 120. The memory 118 can be a U disk, a mobile hard disk, an SD card, a read-only memory 118 (ROM, Read-Only Memory), a random access memory 118 (RAM, Random Access Memory), a disk or an optical disk, etc., which can store data. The memory 118 is used to store the calculation results of the acquisition controller 101 and the received original acquisition data. The display device 119 can be an LCD display screen, an HMI touch screen, a PC computer or a PAD, etc. The measurement personnel interact with the acquisition controller 101 through the display device 119, receive and display the measurement results, or receive the measurement personnel's instructions and transmit them to the acquisition controller 101. For example, the measurement personnel can input the sampling frequency f to the acquisition controller 101 through the display device 119, and the sampling interval is 1 / f. If it is not input, the system default value can be used. The output interface 120 can be a CAN interface, etc. The acquisition controller 101 connects to external devices and outputs the calculation results and original acquisition data through the output interface 120.

[0081] In some examples, the acquisition controller 101 includes a receiving unit, a computing unit, and a control unit. The receiving unit is used to receive the voltage values ​​obtained by the analog-to-digital converter A 106, the analog-to-digital converter B 107, and the analog-to-digital converter C 108, and the temperature values ​​obtained by the analog-to-digital converter D 112, the analog-to-digital converter E 113, and the analog-to-digital converter F 114. The computing unit is used to calculate the energy flow of the vehicle-mounted low-voltage load 203 according to the received voltage value. The control unit is used to control the opening and closing of the switch A 104 and the switch B 105, realize the current measurement mode switching, overload protection startup and other scenes, ensure that the system can maintain the best operating performance under different working conditions, and ensure the smooth progress of the entire test process. As an example and not a limitation, the acquisition controller 101 can be a single-chip microcomputer, an STM board, etc., can be connected to various expansion chips or modules, write control scripts, and collect, analyze, process, transmit, store and output measurement results and alarm information and control the work of each expansion chip and module.

[0082] In some examples, the vehicle low-voltage load energy flow test system 100 further includes a buzzer 121. The buzzer 121 may be an external expansion device in this example, or may be built into the acquisition controller 101. The buzzer 121 may be an active buzzer 121 or a passive buzzer 121. When the acquisition controller 101 determines that the system is abnormal, it controls the buzzer 121 to start.

[0083] Preferably, switch A 104 and switch B 105 can be electromagnetic relays, MOS tubes, etc.

[0084] Figure 2 The flowchart of a vehicle low-voltage load energy flow test method according to an embodiment of the present invention is shown. As shown in the figure, the present invention also provides a vehicle low-voltage load energy flow test method, which is applicable to the vehicle low-voltage load energy flow test system 100 described above. The vehicle low-voltage load energy flow test method includes:

[0085] S1, unload the original fuse in the vehicle fuse box 202. The original fuse is plugged into the corresponding fuse plug port on the existing vehicle fuse box 202. When the circuit is in a closed state, the vehicle low-voltage load 203 is powered by the vehicle battery 201. Therefore, before testing, the original fuse needs to be unloaded to avoid interference with the test caused by the original fuse.

[0086] S2, connect the shunt A 102, shunt B 103 and switch A 104 of the test system 100 in series, and connect them to the terminals A and B of the vehicle-mounted fuse box 202, and connect the analog-to-digital converter C 108 to the vehicle-mounted battery 201. When the shunt A 102, shunt B 103 and switch A 104 are connected in series to the vehicle-mounted low-voltage load 203 circuit, the function of the original fuse is replaced by switch A 104 and / or switch B 105, so that there is no need to consider the problem of the original fuse during the entire measurement process. The purpose of protecting the vehicle-mounted low-voltage load 203 circuit can be achieved by simply controlling the disconnection of switch A 104. It should be noted that all devices except shunt A 102 and shunt B 103 are powered by an external power supply to ensure stable operation of the system.

[0087] S3, close switch A 104 and switch B 105. If the real-time current I is greater than or equal to the threshold current I θ , then it is determined that the real-time current I measurement is valid, because the shunt A is a milliohm-level precision resistor, which can achieve high-precision current measurement;

[0088] If the real-time current I is less than the threshold current I θ , then the switch B 105 is turned off. If the updated real-time current I is less than the threshold current I θ , then it is determined that the real-time current I measurement is valid. The shunt B is an ohm-level precision resistor and is suitable for measuring a relatively larger current range.

[0089] S4, calculate the energy flow of the vehicle's low-voltage load.

[0090] In some examples, in step S4, if switch A 104 and switch B 105 are closed and the real-time current I measurement is valid, the acquisition controller 101 calculates the difference between the real-time voltage U3 of the vehicle battery 201 obtained by the analog-to-digital converter C 108 and the real-time voltage value U1 obtained by the analog-to-digital converter A 106 as the real-time voltage U of the vehicle low-voltage load 203. The real-time current I is obtained by dividing the real-time voltage U1 of the shunt A 102 read by the analog-to-digital converter A 106 by the resistance value R1 of the shunt A 102. The real-time power P of the vehicle low-voltage load 203 is calculated based on the real-time voltage U and the real-time current I, and the energy consumption E of the vehicle low-voltage load 203 is obtained by integration.

[0091] If switch A 104 is closed, switch B 105 is open, and the real-time current I measurement is valid, the acquisition controller 101 calculates the real-time voltage U of the vehicle-mounted low-voltage load 203 by using the real-time voltage U3 of the vehicle-mounted battery 201 obtained by the analog-to-digital converter C 108, the real-time voltage value U1 obtained by the analog-to-digital converter A 106, and the real-time voltage value U2 obtained by the analog-to-digital converter B 107. The real-time current I is obtained by dividing the real-time voltage U2 of the shunt B 103 read by the analog-to-digital converter B 107 by the resistance value R2 of the shunt B 103. The real-time power P of the vehicle-mounted low-voltage load 203 is calculated based on the real-time voltage U and the real-time current I, and the energy consumption E of the vehicle-mounted low-voltage load 203 is obtained by integration.

[0092] Subsequently, the acquisition controller 101 transmits the real-time current I, real-time voltage U, real-time power P, energy consumption E and time t to the display device 119 for real-time monitoring by the measurement personnel. At the same time, the measurement results are recorded in the memory 118 in the format of .cvs, .mf4, etc. In addition, the acquisition controller 101 also transmits the data to the external device through the output interface 120.

[0093] In some examples, in step S3, if the real-time current I exceeds the fuse current Imax, the acquisition controller 101 disconnects the switch A 104 and controls the buzzer 121 to alarm. At the same time, the acquisition controller 101 outputs an alarm message through the display device 119, and automatically saves all data information at this time in the device log, and the measurement stops automatically, thereby protecting the safety of the vehicle-mounted low-voltage load 203 circuit. If any of the real-time temperature T1 of the shunt A 102, the real-time temperature T2 of the shunt B 103, and the temperature T3 of the connection terminals A and B obtained by the temperature sensor A 109, the temperature sensor B 110, and the temperature sensor C 111 is less than the temperature threshold Tmin (the lowest temperature set by the system) or greater than the temperature threshold Tmax (the highest temperature set by the system), the switch A 104 is disconnected and the buzzer 121 is controlled to alarm. At the same time, the acquisition controller 101 outputs an alarm message through the display device 119, and automatically saves all data information at this time in the device log, and the measurement stops automatically, thereby protecting the safety of the vehicle-mounted low-voltage load 203 circuit.

[0094] In some examples, after step S2 and before executing step S3, the resistance R1 of shunt A 102 is obtained by resistance measurement module A 115, and the resistance R2 of shunt B 103 is obtained by resistance measurement module B 116. When the measurement personnel believe that the default resistance value or input resistance value of shunt A 102 and / or shunt B 103 has deviated from the actual value, in order to ensure the accuracy and reliability of the measurement, the resistance values ​​of shunt A 102 and shunt B 103 can be measured and calibrated. The measurement personnel can issue a calibration instruction to the acquisition controller 101 through the interactive interface of the display device 119, and then the acquisition controller 101 puts the switch A 104 in the disconnected state, and the resistance measurement module A 115 and the resistance measurement module B 116 corresponding to the shunt A 102 and the shunt B 103 respectively measure the actual resistance value and refresh the input resistance value of the corresponding shunt in the acquisition controller 101.

[0095] The vehicle low-voltage load energy flow test system and test method provided by the present invention have the following advantages:

[0096] 1. Abandon the traditional blown fuse during the measurement process, and protect the load circuit by controlling the closing and opening of the switch through the acquisition controller. There is no need to prepare different fuse connectors or replacement fuses during the test, which significantly reduces the test preparation cost.

[0097] 2. In the measurement process, both ohm-level shunt and milliohm-level shunt are used. In the measurement process, the set threshold current is used to determine whether the ohm-level shunt is connected in series with the measured circuit. The milliohm-level shunt is used to measure larger currents. When the current is smaller, it is automatically switched to the ohm-level shunt for measurement. The realization of the dynamic range automatic switching function can effectively ensure the test accuracy and improve the effective measurement range.

[0098] 3. During the measurement process, the voltage division phenomenon caused by the shunt in the original circuit of the on-board low-voltage load is fully considered. The real-time voltage of the on-board battery is subtracted from the real-time voltage at both ends of the shunt connected in series to correct the voltage of the on-board low-voltage load circuit, so that the calculated energy consumption result is closer to the actual situation, which is of great significance for accurately grasping the energy distribution and consumption of the vehicle in the subsequent energy flow analysis process.

[0099] 4. Set up an automatic alarm and recording system during the measurement process. When a fault occurs, the loop switch can be automatically disconnected, the buzzer alarm can be sounded, and the alarm information can be sent and all current data can be saved, which is convenient for measurement personnel to troubleshoot problems and effectively protect measurement equipment, significantly reducing the cost of troubleshooting and maintenance.

[0100] 5. Introduce the resistance measurement module during the measurement process to realize the measurement and calibration of the real-time resistance value of the shunt. By correcting the resistance value of the shunt, the influence of environmental factors such as temperature, humidity and other conditions on the measurement results can be avoided, which significantly increases the accuracy and reliability of the measurement data and also improves the service life of the measurement equipment.

[0101] It will be apparent to those skilled in the art that various modifications and variations may be made to the above exemplary embodiments of the present invention without departing from the spirit and scope of the present invention. Therefore, it is intended that the present invention covers modifications and variations of the present invention that fall within the scope of the appended claims and their equivalent technical solutions.

Claims

1. A vehicle low-voltage load energy flow test system, the vehicle comprising a vehicle-mounted battery, a vehicle-mounted fuse box and a vehicle-mounted low-voltage load connected in series, the vehicle low-voltage load energy flow test system comprising: Acquisition controller; Shunt A, shunt B and switch A are connected in series and connected to terminals A and B of the vehicle fuse box; A switch B is connected in parallel with the shunt B; Analog-to-digital converter A and analog-to-digital converter B are connected in parallel with the shunt A and shunt B respectively, and the analog-to-digital converter A and analog-to-digital converter B are used to obtain the voltage values ​​of the shunt A and shunt B and send them to the acquisition controller; An analog-to-digital converter C is used to obtain the voltage value of the vehicle-mounted battery and send it to the acquisition controller; The temperature sensor A, the temperature sensor B and the temperature sensor C are used to obtain the temperature values ​​of the shunt A, the shunt B and the connection terminals A and B respectively; Analog-to-digital converter D, analog-to-digital converter E and analog-to-digital converter F are respectively connected to the temperature sensor A, temperature sensor B and temperature sensor C, and the temperature values ​​obtained by the temperature sensor A, temperature sensor B and temperature sensor C are sent to the acquisition controller; The acquisition controller calculates the energy flow of the vehicle-mounted low-voltage load according to the received voltage value.

2. The vehicle low-voltage load energy flow test system according to claim 1, characterized in that: The shunt A is a precision resistor at the milliohm level, and the shunt B is a precision resistor at the ohm level.

3. The vehicle low-voltage load energy flow test system according to claim 2, characterized in that: It also includes a resistance measurement module A and a resistance measurement module B, which are respectively connected in parallel with the shunt A and the shunt B. The resistance measurement module A and the resistance measurement module B are used to obtain the resistance values ​​of the shunt A and the shunt B and send them to the acquisition controller.

4. The vehicle low-voltage load energy flow test system according to claim 1, characterized in that: It also includes a timer connected to the acquisition controller.

5. The vehicle low-voltage load energy flow test system according to claim 1, characterized in that: It also includes a memory, a display device and an output interface. The memory is used to store the calculation results of the acquisition controller and the received original acquisition data. The measurement personnel interact with the acquisition controller through the display device. The acquisition controller is connected to external equipment through the output interface and outputs the calculation results and the original acquisition data.

6. The vehicle low-voltage load energy flow test system according to claim 1, characterized in that: The acquisition controller includes a receiving unit, a calculating unit and a control unit. The receiving unit is used to receive voltage values ​​and temperature values. The calculating unit is used to calculate the energy flow of the vehicle-mounted low-voltage load according to the received voltage value. The control unit is used to control the opening and closing of the switch A and the switch B.

7. A vehicle low-voltage load energy flow test method, applicable to the vehicle low-voltage load energy flow test system according to claim 3, characterized in that: The vehicle low-voltage load energy flow test method comprises: S1, unloading the original fuse in the vehicle fuse box; S2, connect the shunt A, shunt B and switch A of the test system in series, and connect them to terminals A and B of the vehicle fuse box; connect the analog-to-digital converter C to the vehicle battery; S3, close the switch A and switch B, if the real-time current I is greater than or equal to the threshold current I θ , then it is determined that the real-time current I measurement is valid; If the real-time current I is less than the threshold current I θ , then disconnect the switch B, if the updated real-time current I is less than the threshold current I θ , then it is determined that the real-time current I measurement is valid; S4, calculating the energy flow of the low-voltage load of the vehicle.

8. The vehicle low-voltage load energy flow test method according to claim 7, characterized in that: In step S4, if the switch A and the switch B are closed and the real-time current I measurement is valid, the difference between the real-time voltage U3 of the vehicle battery obtained by the analog-to-digital converter C and the real-time voltage value U1 obtained by the analog-to-digital converter A is used as the real-time voltage U of the vehicle low-voltage load; the real-time power P of the vehicle low-voltage load is calculated based on the real-time voltage U and the real-time current I, and the energy consumption E of the vehicle low-voltage load is obtained by integration; If the switch A is closed, the switch B is open, and the real-time current I measurement is valid, the real-time voltage U3 of the vehicle battery obtained by the analog-to-digital converter C, the real-time voltage value U1 obtained by the analog-to-digital converter A and the real-time voltage value U2 obtained by the analog-to-digital converter B are used to calculate the real-time voltage U of the vehicle low-voltage load; the real-time power P of the vehicle low-voltage load is calculated based on the real-time voltage U and the real-time current I, and the energy consumption E of the vehicle low-voltage load is obtained by integration.

9. The vehicle low-voltage load energy flow test method according to claim 7, characterized in that: In step S3, if the real-time current I exceeds the fuse current Imax, the switch A is disconnected; if any one of the real-time temperature T1 of the shunt A, the real-time temperature T2 of the shunt B, and the temperature T3 of the terminals A and B obtained by the temperature sensor A, the temperature sensor B, and the temperature sensor C is less than the temperature threshold Tmin or greater than the temperature threshold Tmax, the switch A is disconnected.

10. The vehicle low-voltage load energy flow test method according to claim 7, characterized in that: After step S2 and before executing step S3, the resistance R1 of the shunt A is obtained by the resistance measurement module A, and the resistance R2 of the shunt B is obtained by the resistance measurement module B.

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