Electromagnetic emission quantity test system and test method

Abstract

The invention discloses an electromagnetic emission quantity test system and test method, belongs to the technical field of electric automobiles, and solves the problem of how to improve the electromagnetic emission quantity test accuracy of an automobile power battery pack assembly. The low-voltage electromagnetic emission quantity testing unit is connected with an automobile power battery pack assembly through a low-voltage wire harness, the high-voltage electromagnetic emission quantity testing unit is connected with the automobile power battery pack assembly through a high-voltage wire harness, and the testing units are used for testing the electromagnetic emission quantity of the low-voltage electromagnetic emission quantity testing unit and the high-voltage electromagnetic emission quantity testing unit and sending a testing result to the control unit; through reasonable layout of the control unit, the low-voltage electromagnetic emission quantity test unit, the high-voltage electromagnetic emission quantity test unit and the test unit, electromagnetic emission quantity tests on low-voltage wiring harnesses and high-voltage wiring harnesses of various test conditions of an automobile power battery pack assembly can be completed only by building the test system for one time, and the accuracy of test results is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric vehicles and relates to an electromagnetic emission measurement system and a measurement method. Background Art

[0002] With the rapid development and change of new energy vehicle technology, the types of in-vehicle electronic products tend to be more integrated and intelligent. As the main types of current-stage battery cells, lithium iron phosphate and NCM ternary batteries, combined with battery management systems designed according to different requirements, form the electric vehicle power battery pack assembly. With the electric vehicle entering a new stage of development, there are also higher requirements for the electromagnetic compatibility of the vehicle power battery pack assembly.

[0003] The conducted emission test measures the electromagnetic emissions of power lines and signal lines under different working conditions of components, so as to evaluate whether it will cause damage to the performance degradation of other electronic devices in the vehicle or interfere with their normal functions. As the power source of current pure electric vehicle models, range-extended vehicle models and other new energy vehicle models, the electric vehicle power battery pack assembly has different working conditions. Whether other electrical appliances on the vehicle will be affected by its working conditions, such as drive motors, DC / DC converters, etc., is directly related to driving safety. Therefore, the conducted emission test is also an indispensable measurement test in the development stage of the electric vehicle power battery pack assembly.

[0004] The conducted emission test system and test method of the prior art are mainly implemented in accordance with the standard CISPR 25:2021; the main components of the test system in Figures 13 on page 56 and Figure H.5 on page 113 of the standard CISPR 25:2021 are: a shielded control room, an anechoic chamber test room, and a power distribution room. Generally, the measuring equipment is placed in the shielded control room. The shielded control room and the anechoic chamber test room are adjacent. Copper, brass, bronze, or galvanized steel with a thickness of at least 0.5 mm is laid on the test bench inside the anechoic chamber. The total length of the test bench needs to be ≥ 2500 mm, and its width needs to ensure a distance of ≥ 100 mm from the lower edge of the device under test, a distance of ≥ 500 mm from the upper edge of the device under test, and the wire harness and the device under test are placed on an insulating support material with a low dielectric constant and a thickness of 50 mm. The total length of the wire harness is greater than or equal to 1700 mm and does not exceed 2000 mm. The low-voltage load and external equipment are connected through an optical fiber feedthrough system. The low-voltage power supply line is connected to a low-voltage artificial network, and the high-voltage power supply line is connected to a high-voltage artificial network (the high-voltage network is connected to the power supply). The current probe is connected to the measuring equipment through a waveguide connector; the specific steps for testing the low-voltage wire harness of the vehicle-mounted parts under test are: clamp the wire harness to be tested with the current probe. There are 2 measurement positions, which are 50 mm from the wire harness interface and 750 mm from the wire harness interface respectively. Then connect the current probe and the measuring equipment with a coaxial cable. When the sample is in the working state, turn on the measuring equipment to measure the conducted emission electromagnetic wave and compare it with the standard value to evaluate whether it will affect other electronic devices. The specific steps for testing the high-voltage wire harness of the vehicle-mounted parts under test are: similarly, clamp the wire harness to be tested with the current probe. The test position is the same as that of the low-voltage wire harness, and the subsequent steps are also the same as those of the low-voltage wire harness.

[0005] The conducted emission test system and test method of the prior art mainly have the following disadvantages:

[0006] 1) In the prior art, for the test system in CISPR 25:2021, generally, after the test environment is set up, if the working mode of the sample is changed, the test environment needs to be set up again, and it is impossible to directly switch multiple modes for testing in the control room. In the same test project, if the test environment changes multiple times, it is easy to increase the uncertainty in the operation of the test personnel and affect the accuracy of the test results.

[0007] 2) During the automotive verification and development stage, it has been found through practice that in the standard CISPR 25:2021, the measurement position 50 mm from the wire harness interface cannot be satisfied on the automotive power battery pack assembly. Because considering the internal layout, the distance between the positive and negative wires of the high-voltage wire harness will increase, resulting in the current probe being unable to clamp at this distance; and if the test positions are not unified, it will affect the consistency of the measurement results of the conducted emission test of the automotive power battery pack assembly.

[0008] 3) The dimensions of the test bench and the thickness of the copper plate in the standard CISPR 25:2021 only give the lower limits, and there is no practical case for actual use. Especially for the application of automotive power battery pack assemblies, a relatively small test bench size may lead to the inability to conduct tests, while designing an overly large test bench size will result in a sharp increase in the cost of building a shielding room. The same is true for the copper plate thickness. Since the volume and weight of automotive power battery pack assemblies are much larger than those of other in-vehicle devices, evaluations and actual tests need to be carried out in this regard.

[0009] 4) The power line filter in the standard CISPR 25:2021 only requires that the ambient test noise be lower than 6 dB before testing, without considering the insulation resistance detection and protection strategy of automotive power battery pack assemblies. Due to the characteristics of general filters, when the high-voltage power line of the automotive power battery pack assembly is powered on, the insulation resistance value between the high-voltage line and the ground will be lower than 0.8 MΩ. In this case, the insulation resistance detection and protection strategy of the automotive power battery pack assembly will immediately disconnect the high-voltage relay. In practice, it is found that many laboratories shield the software insulation resistance detection and protection strategy to continue the test, which brings many potential hazards to the safety of test personnel and equipment.

[0010] 5) The terminal connected to the high-voltage power line in the test system of the standard CISPR 25:2021 is the high-voltage power supply, without considering the working mode of the automotive power battery pack assembly. According to the requirements of this system, the high-voltage power line is connected to the high-voltage power supply. After configuring the system, only the automotive power battery pack assembly can be charged. If the discharge mode is to be carried out, the high-voltage line on the power supply needs to be disconnected and reconnected to the high-voltage load. In the verification and development tests, it is often necessary to compare the conducted emission electromagnetic wave emission amounts in multiple modes, and the frequent switching brings safety risks and an increase in manual time consumption.

[0011] 6) When the automotive power battery pack assembly needs temperature control in the test system of the standard CISPR 25:2021, there are no supporting facilities that can be used. Moreover, if the structure of the shielding room is changed later, it will have a greater impact on the overall shielding efficiency of the shielding room.

[0012] 7) In the test system of the standard CISPR 25:2021, the control terminal of the high-voltage power supply is not clear. According to this standard, the high-voltage power supply is still controlled by the power supply panel. Personnel operate inside the shielding room, which is inconvenient and it is not easy to observe the status of the high-voltage power supply. Moreover, when personnel operate inside the shielding room, there is a great safety hazard that the high-voltage power supply may be accidentally turned on. Summary of the Invention

[0013] The technical solution of the present invention is used to solve the problem of how to improve the test accuracy of the electromagnetic emission amount of automotive power battery pack assemblies.

[0014] The present invention solves the above technical problems through the following technical solutions:

[0015] The present invention provides an electromagnetic emission measurement system, including: a control unit, a low-voltage electromagnetic emission measurement unit, a high-voltage electromagnetic emission measurement unit, and a measurement unit; the control unit is respectively connected to the low-voltage electromagnetic emission measurement unit, the high-voltage electromagnetic emission measurement unit, and the measurement unit. The low-voltage electromagnetic emission measurement unit is connected to the automotive power battery pack assembly through a low-voltage wire harness, and the high-voltage electromagnetic emission measurement unit is connected to the automotive power battery pack assembly through a high-voltage wire harness. The measurement unit is used to measure the electromagnetic emissions of the low-voltage electromagnetic emission measurement unit and the high-voltage electromagnetic emission measurement unit, and send the test results to the control unit; the tester only needs to operate the control unit to complete the switching of the test conditions of the automotive power battery pack assembly.

[0016] Further, the electromagnetic emission measurement system of the present invention further includes: a cooling unit, the cooling unit is connected to the automotive power battery pack assembly through a pipeline, and the control network cable of the cooling unit is connected to the control unit.

[0017] Further, the electromagnetic emission measurement system of the present invention further includes: a low-voltage power supply unit, the low-voltage power supply unit is connected to the low-voltage electromagnetic emission measurement unit.

[0018] Further, the control unit of the electromagnetic emission measurement system of the present invention includes: a control computer, a USBCAN transceiver device, a radio frequency signal source, a first module of a CANFD optical-electric converter, and a first module of a PWM waveform optical-electric converter; the low-voltage electromagnetic emission measurement unit includes: a power supply, an artificial power network, a second module of a CANFD optical-electric converter, and a second module of a PWM waveform optical-electric converter; the high-voltage electromagnetic emission measurement unit includes: a power battery pack test system and a high-voltage system dedicated artificial power network; the power supply, the artificial power network, and the low-voltage wire interface of the automotive power battery pack assembly are connected in sequence; the power supply wire of the power battery pack test system, the high-voltage system dedicated artificial power network, and the high-voltage wire interface of the automotive power battery pack assembly are connected in sequence, and the control network cable of the power battery pack test system is connected to the control computer; the CAN signal line of the low-voltage wire interface, the second module of the CANFD optical-electric converter, the first module of the CANFD optical-electric converter, the USBCAN transceiver device, and the control computer are connected in sequence; the collision signal line of the low-voltage wire interface, the second module of the PWM waveform optical-electric converter, the first module of the PWM waveform optical-electric converter, and the radio frequency signal source are connected in sequence.

[0019] Further, the measurement unit of the electromagnetic emission measurement system of the present invention includes: a measurement receiver and a current probe; the current probe is connected to the measurement receiver by a coaxial cable, and the control network cable of the measurement receiver is connected to the control unit; when measuring the electromagnetic emission, the current probe is clamped at 300 mm and 750 mm away from the automotive power battery pack assembly respectively.

[0020] Further, the cooling unit of the electromagnetic emission measurement system of the present invention includes: a cooling device and a cooling pipe interface; the cooling device is connected to the cooling pipe interface through a pipeline, the cooling pipe interface is connected to the automotive power battery pack assembly through a pipeline, and the control network cable of the cooling device is connected to the control unit.

[0021] Further, the low-voltage power supply unit of the electromagnetic emission measurement system of the present invention includes: a linear DC voltage stabilizer and a DC filter, the linear DC voltage stabilizer is connected to the DC filter, and the DC filter is connected to the low-voltage electromagnetic emission measurement unit.

[0022] Further, the electromagnetic emission measurement system of the present invention further includes a test bench, on which a grounding copper plate is laid, and the power supply, artificial power network, special artificial power network for high-voltage system, the second module of the CANFD optical-electric converter, and the second module of the PWM waveform optical-electric converter are all arranged on the grounding copper plate; an insulating material support plate is laid on the grounding copper plate, and the automotive power battery pack assembly and its high- and low-voltage wire harnesses are all placed on the insulating material support plate.

[0023] Preferably, the power supply is a lead-acid battery, a lithium battery, a nickel-metal hydride battery or an alkaline battery.

[0024] The present invention also provides an electromagnetic emission measurement method based on the above electromagnetic emission measurement system, including the following steps:

[0025] Set the sweep frequency parameters, collision signal parameters, operating conditions parameters of the automotive power battery pack assembly and the parameters for controlling the automotive power battery pack assembly in the control unit;

[0026] The control unit switches different test conditions of the automotive power battery pack assembly;

[0027] The measurement unit first measures the electromagnetic emission of the low-voltage wire harness of the low-voltage electromagnetic emission measurement unit, and then measures the electromagnetic emission of the high-voltage wire harness of the high-voltage electromagnetic emission measurement unit;

[0028] Compare the data obtained from each test condition with the standard data respectively.

[0029] Advantages of the technical solution of the present invention:

[0030] 1) The test system of the present invention is applicable to various test conditions of automotive power battery pack assemblies. Only one test operator needs to set up the test system once, and then can conveniently and quickly switch test conditions by operating the control computer in the control room, complete the electromagnetic emission measurement on the low-voltage harness and high-voltage harness of the automotive power battery pack assembly under various test conditions. The test process of the test items is more smooth, ensuring the accuracy of the test results. At the same time, it reduces manual time consumption, increases convenience, and greatly improves the test efficiency.

[0031] 2) The technical solution of the present invention does not specifically limit the sample specifications of the test, and can be applied to the electromagnetic emission measurement test of automotive power battery pack assemblies of various sizes for passenger cars, with good versatility.

[0032] 3) The technical solution of the present invention can be linked with water-cooling / air-cooling equipment as needed.

[0033] 4) The technical solution of the present invention centralizes the sample operation state, equipment control state, and test curve test state on a single control computer that is convenient for a single person to monitor. It can directly and timely observe the safety state of the automotive power battery pack assembly, and the control parameters of the test equipment can also be centrally controlled, making it more intuitive for the supervisor to supervise the test process, and ensuring no missed measurements and no wrong measurements. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is the structural diagram of the electromagnetic emission measurement system according to Embodiment 1 of the present invention;

[0035] The reference numerals are as follows:

[0036] 30 - Control room, 31 - Control computer, 32 - Measuring receiver, 33 - USBCAN transceiver device, 34 - RF signal source, 35 - Waveguide window, 36 - Waveguide interface board;

[0037] 40 - Test room, 41 - Ground copper plate, 42 - Insulating material support plate, 43 - Power supply interface board, 44 - Power supply, 45 - Artificial power network, 46 - Special artificial power network for high-voltage system, 47 - CANFD optical-electric converter, 48 - PWM waveform optical-electric converter, 49 - Cooling pipe interface;

[0038] 50 - Automotive power battery pack assembly, 51 - Low-voltage wire interface, 52 - High-voltage wire interface, 53 - Current probe;

[0039] 60 - Power battery pack test system, 61 - Linear DC regulated power supply, 62 - DC filter, 63 - Special DC filter for high-voltage system, 64 - Air-cooling equipment, 65 - Water-cooling equipment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0041] The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings of the specification and specific embodiments:

[0042] Embodiment 1

[0043] As Figure 1 shown, the structure of the conduction emission current method electromagnetic emission measurement system for the power battery pack assembly in the embodiment of the present invention includes: a control room 30 and a test room 40.

[0044] A control computer 31, a measurement receiver 32, a USBCAN transceiver device 33, a radio frequency signal source 34, the first module of the CANFD optical-electric converter 47, and the first module of the PWM waveform optical-electric converter 48 are arranged in the control room 30; two waveguide windows 35 and two waveguide interface boards 36 are arranged on the wall of the control room 30.

[0045] A test bench is arranged in the test room 40. A grounding copper plate 41 is laid on the test bench, and an insulating material support plate 42 is laid on the grounding copper plate 41. The automotive power battery pack assembly 50 and its high- and low-voltage wiring harnesses are all placed on the insulating material support plate 42; a power supply 44, an artificial power network 45, a special artificial power network 46 for the high-voltage system, the second module of the CANFD optical-electric converter 47, and the second module of the PWM waveform optical-electric converter 48 are all arranged on the grounding copper plate 41; a power interface board 43 and a cooling pipe interface 49 are respectively arranged inside the test room 40 and beside the test bench.

[0046] The test room 40 can be selected as a shielded room or a semi-anechoic chamber.

[0047] A power battery pack test system 60, a linear DC regulated power supply 61, a DC filter 62, a special DC filter 63 for the high-voltage system, an air-cooling device 64, and a water-cooling device 65 are all arranged outside the test room 40.

[0048] The air-cooling pipe of the air-cooled type automotive power battery pack assembly 50 is connected to the air-cooling device 64 through the cooling pipe interface 49; the water-cooling pipe of the water-cooled type automotive power battery pack assembly 50 is connected to the water-cooling device 65 through the cooling pipe interface 49.

[0049] A cooling pipe interface is set at the lower right of the test bench, with an air-cooling pipe and a water-cooling pipe reserved. The air flow rate through the air-cooling pipe can be at least 30 m 3 / min, and the liquid flow rate through the water-cooling pipe can be at least 30 L / min. The air-cooling pipe, the water-cooling pipe and their joints all adopt a double-layer shielding design. At the same time, an optical fiber waveguide interface board is reserved beside the pipeline, and a CANFD photoelectric converter can be used to transmit the CAN message information of the automotive power battery pack assembly to the air-cooling device or the water-cooling device, which can be used in matching when the automotive power battery pack assembly needs temperature control.

[0050] The control network cable of the power battery pack test system 60 is connected to the control computer 31 through a waveguide window 35 on the control room 30. The power supply line of the power battery pack test system 60 is connected to the special DC filter 63 for the high-voltage system. The special DC filter 63 for the high-voltage system is connected to the special artificial power network 46 for the high-voltage system through the power interface board 43, and the special artificial power network 46 for the high-voltage system is connected to the high-voltage wire interface 52 of the automotive power battery pack assembly 50. Considering the working mode of the automotive power battery pack assembly 50, the terminal connected by the high-voltage power supply line is the power battery pack test system 60. After connecting the high-voltage wire harness, the test working conditions of the power battery pack test system 60 can be quickly and conveniently switched and the warning value can be set through the control computer 31. The power battery pack test system 60 can be used as a charging power supply or a discharge load. After setting the warning value in the control computer 31, the SOC / mono-cell voltage of the automotive power battery pack assembly 50 received through the CANFD fiber converter 47 is fed back to the control computer 31 for real-time warning to prevent overcharging and over-discharging.

[0051] The linear DC regulated power supply 61 is connected to the DC filter 62. The DC filter 62 is connected to the power supply 44 through the power interface board 43. The power supply 44 is connected to the artificial power network 45, and the artificial power network 45 is connected to the low-voltage wire interface 51 of the automotive power battery pack assembly 50.

[0052] The control network cables of the air-cooling device 64 and the water-cooling device 65 are connected to the control computer 31 through another waveguide window 35 on the control room 30. The control network cable of the measuring receiver 32 is connected to the control computer 31.

[0053] When measuring the electromagnetic emission amount, current probes 53 are respectively clamped at 300 mm and 750 mm away from the low-voltage wire interface 51 or the high-voltage wire interface 52 of the automotive power battery pack assembly 50. The output ends of the current probes 53 are respectively connected to the measuring receiver 32 through coaxial cables via the waveguide interface board 36; the two current probes 53 are first clamped on the low-voltage wire harness to measure the electromagnetic emission amount on the low-voltage wire harness, and then clamped on the high-voltage wire harness to measure the electromagnetic emission amount on the high-voltage wire harness.

[0054] The CAN signal line of the low-voltage line interface 51 is connected to one end of the second module of the CANFD optoelectronic converter 47 provided on the grounding copper plate 41. The other end of the second module of the CANFD optoelectronic converter 47 is connected to one end of the first module of the CANFD optoelectronic converter 47 through the waveguide interface board 36. The other end of the first module of the CANFD optoelectronic converter 47 is connected to the USBCAN transceiver device 33. The collision signal line of the low-voltage line interface 51 is connected to one end of the second module of the PWM waveform optoelectronic converter 48 provided on the grounding copper plate 41. The other end of the second module of the PWM waveform optoelectronic converter 48 is connected to one end of the first module of the PWM waveform optoelectronic converter 48 through the waveguide interface board 36. The other end of the first module of the PWM waveform optoelectronic converter 48 is connected to the radio frequency signal source 34. The collision signal is emitted by the radio frequency signal source 34 and sent to the automotive power battery pack assembly 50 through the collision signal line by the PWM waveform optoelectronic converter 48. Using the PWM waveform optoelectronic converter 48 to transmit the collision signal avoids the influence of the radio frequency signal source 34 on the test results of the automotive power battery pack assembly 50.

[0055] Preferably, the length of the high-voltage harness between the special artificial power network 46 for the high-voltage system and the automotive power battery pack assembly 50 is 1700 - 2000 mm. The high-voltage harness includes: a high-voltage positive power line and a high-voltage negative power line.

[0056] In the test system of the embodiment of the present invention, considering the insulation resistance detection and protection strategy of the automotive power battery pack assembly in the configuration, due to the characteristics of the general filter, the insulation resistance value of the high-voltage line to the ground will be lower than 0.8 MΩ at the moment when the automotive power battery pack assembly is just powered on with high voltage, and the insulation resistance detection and protection strategy of the automotive power battery pack assembly will immediately disconnect the high-voltage relay in this case. In practice, it is found that many laboratories shield the software insulation resistance detection and protection strategy and continue the test. In the test system of the embodiment of the present invention, when the high-voltage relay of the automotive power battery pack assembly 50 is closed, it is required that the insulation detection values of the high-voltage positive power line to the ground and the high-voltage negative power line to the ground are both greater than or equal to 0.8 MΩ. Therefore, a high-voltage power line shielding interface path is set, and the insulation performance of the power battery pack can be detected by connecting to the high-voltage power supply through this path before the test. After the function detection is completed, the path can be isolated from the external electromagnetic environment using a shielding plug.

[0057] Preferably, the length of the low-voltage harness between the artificial power network 45 and the automotive power battery pack assembly 50 is 1700 - 2000 mm. The low-voltage harness includes: a low-voltage power line, a CAN signal line, and a collision signal line.

[0058] The dimensions of the test bench and the thickness of the grounding copper plate 41 in the standard CISPR 25:2021 only give the lower limits, and there is no practical case for actual use. Especially for the automotive power battery pack assembly, preferably, the dimensions of the test bench are set as follows: the length is 4.0 m to 5.0 m, the width is 2.0 m to 3 m, and the height is 0.85 m to 0.95 m, which can meet the test requirements of automotive power battery packs for different specifications of passenger cars.

[0059] Preferably, the thickness of the grounding copper plate 41 is 2 mm to 4 mm; further, defining the thickness of the grounding copper plate 41 as 4 mm can meet the requirement of no deformation under load, and can isolate the risk of burning of the test bench by high temperature when there is a risk of out-of-control of the automotive power battery pack assembly, and gain time for fire fighting.

[0060] Preferably, the thickness of the insulating material support plate 42 is 50 ± 2 mm; in the standard CISPR 25:2021, the thickness range of the insulating material support plate 42 is 50 ± 5 mm. However, in actual applications, in order to prevent the thickness dimension from becoming thinner due to durability after a long service life and resulting in out-of-tolerance, the thickness range of the insulating material support plate 42 is reduced.

[0061] Preferably, the power supply 44 is a lead-acid battery, a lithium battery, a nickel-metal hydride battery or an alkaline battery.

[0062] The conduction emission current method test system for the power battery pack assembly in the embodiment of the present invention can be applied to various different test conditions of the automotive power battery pack assembly 50. The control computer 31 sends CAN signals to the automotive power battery pack assembly 50 through the USBCAN transceiver device 33 and the CANFD optical-electric converter 47, and controls the switching state of the high-voltage relay of the automotive power battery pack assembly 50 according to the CAN signals, so as to control the high-voltage power-on and power-off or enter the sleep state of the automotive power battery pack assembly 50. The control computer 31 controls the power battery pack test system 60 to match the charging or discharging conditions of the automotive power battery pack assembly 50, and monitors the charging or discharging current at the same time. The control computer 31 controls the air-cooling device 64 to perform air cooling on the air-cooled automotive power battery pack assembly 50 when the air-cooling condition is reached, or the control computer 31 controls the water-cooling device 65 to perform water cooling on the water-cooled automotive power battery pack assembly 50 when the water-cooling condition is reached. A single test operator only needs to build the test system once, and can operate the control computer 31 in the control room 30 to conveniently and quickly switch the test conditions, and complete the tests of slow charging, fast charging, slow discharging, fast discharging, water cooling, air cooling and other test conditions of the automotive power battery pack assembly 50; for example, the conduction emission current method measurement is carried out on the automotive power battery pack assembly under the water-cooling pipeline condition of the anechoic chamber when the automotive power battery pack assembly is in the sleep state or the charging state or the driving mode of 200 A discharging.

[0063] Embodiment 2

[0064] The method for measuring the electromagnetic emission amount using the electromagnetic emission amount test system in Embodiment 1 is as follows:

[0065] 1) Turn on the measurement receiver 32, turn on the control computer 31. After setting the frequency sweep parameters in the control computer 31, the control computer 31 controls the measurement receiver 32 at this time;

[0066] 2) Turn on the power battery pack test system 60. After setting the working condition parameters of the automotive power battery pack assembly 50 (such as: charging current value, discharging current value, current limit, current parameter, water-cooling or air-cooling linkage signal parameter) in the control computer 31, the control computer 31 controls the power battery pack test system 60 at this time;

[0067] 3) Turn on the air-cooling device 64 or the water-cooling device 65. After setting the trigger parameters in the control computer 31, the control computer 31 controls the air-cooling device 64 or the water-cooling device 65 at this time;

[0068] 4) Turn on the radio frequency signal source 34 and set the collision signal parameters, then turn on the PWM waveform optoelectronic converter 48;

[0069] 5) Turn on the power supply 44 switch, then turn on the CANFD optoelectronic converter 47, and at the same time turn on the CAN signal tool software on the control computer 31, and set the parameters for controlling the automotive power battery pack assembly 50;

[0070] 6) After all the test equipment and the equipment under test are warmed up for 10 minutes, adjust the test working condition of the automotive power battery pack assembly 50 through the control computer 31;

[0071] 7) Clamp the current probe 53 on the low-voltage wire harness, measure the electromagnetic emission amount on the low-voltage wire harness, and compare the collected data with the standard data;

[0072] 8) Clamp the current probe 53 on the high-voltage wire harness, measure the electromagnetic emission amount on the high-voltage wire harness, and compare the collected data with the standard data.

[0073] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electromagnetic emission quantity testing system, characterized in that Including: A control unit, a low-voltage electromagnetic emission measurement unit, a high-voltage electromagnetic emission measurement unit, and a measurement unit; the control unit is respectively connected to the low-voltage electromagnetic emission measurement unit, the high-voltage electromagnetic emission measurement unit, and the measurement unit. The low-voltage electromagnetic emission measurement unit is connected to the automotive power battery pack assembly through a low-voltage harness, and the high-voltage electromagnetic emission measurement unit is connected to the automotive power battery pack assembly through a high-voltage harness. The measurement unit is used to measure the electromagnetic emissions of the low-voltage electromagnetic emission measurement unit and the high-voltage electromagnetic emission measurement unit, and send the test results to the control unit; the test personnel only need to operate the control unit to complete the switching of the test conditions of the automotive power battery pack assembly.

2. The electromagnetic emission measurement system according to claim 1, wherein Also including: A cooling unit, the cooling unit is connected to the automotive power battery pack assembly through a pipeline, and the control network cable of the cooling unit is connected to the control unit.

3. The electromagnetic emission measurement system according to claim 1, wherein Also including: A low-voltage power supply unit, the low-voltage power supply unit is connected to the low-voltage electromagnetic emission measurement unit.

4. The electromagnetic emission measurement system according to claim 1, characterized in that The control unit includes: a control computer, a USBCAN transceiver device, a radio frequency signal source, a first module of a CANFD optical-electric converter, and a first module of a PWM waveform optical-electric converter; the low-voltage electromagnetic emission measurement unit includes: a power supply, an artificial power network, a second module of a CANFD optical-electric converter, and a second module of a PWM waveform optical-electric converter; the high-voltage electromagnetic emission measurement unit includes: a power battery pack test system and a high-voltage system dedicated artificial power network; the power supply, the artificial power network, and the low-voltage line interface of the automotive power battery pack assembly are connected in sequence; the power supply line of the power battery pack test system, the high-voltage system dedicated artificial power network, and the high-voltage line interface of the automotive power battery pack assembly are connected in sequence, and the control network cable of the power battery pack test system is connected to the control computer; the CAN signal line of the low-voltage line interface, the second module of the CANFD optical-electric converter, the first module of the CANFD optical-electric converter, the USBCAN transceiver device, and the control computer are connected in sequence; the collision signal line of the low-voltage line interface, the second module of the PWM waveform optical-electric converter, the first module of the PWM waveform optical-electric converter, and the radio frequency signal source are connected in sequence.

5. The electromagnetic emission measurement system according to claim 1, characterized in that, The measurement unit includes: a measurement receiver and a current probe; the current probe is connected to the measurement receiver by a coaxial cable, and the control network cable of the measurement receiver is connected to the control unit; when measuring the electromagnetic emission, the current probe is clamped at 300mm and 750mm away from the automotive power battery pack assembly respectively.

6. The electromagnetic emission measurement system according to claim 2, characterized in that, The cooling unit includes: a cooling device and a cooling pipe interface; the cooling device is connected to the cooling pipe interface through a pipeline, the cooling pipe interface is connected to the automotive power battery pack assembly through a pipeline, and the control network cable of the cooling device is connected to the control unit.

7. The electromagnetic emission measurement system according to claim 2, wherein The low-voltage power supply unit includes: a linear DC regulated power supply and a DC filter, the linear DC regulated power supply is connected to the DC filter, and the DC filter is connected to the low-voltage electromagnetic emission measurement unit.

8. The electromagnetic emission measurement system according to claim 4, characterized in that It further includes a test bench on which a grounding copper plate is laid. The power supply, the artificial power network, the special artificial power network for the high-voltage system, the second module of the CANFD optical-electric converter, and the second module of the PWM waveform optical-electric converter are all arranged on the grounding copper plate. An insulating material support plate is laid on the grounding copper plate, and the automotive power battery pack assembly and its high- and low-voltage wiring harnesses are all placed on the insulating material support plate.

9. The electromagnetic emission measurement system according to claim 8, wherein The power supply is a lead-acid battery, a lithium battery, a nickel-metal hydride battery, or an alkaline battery.

10. A method for measuring electromagnetic emission amount based on the electromagnetic emission amount measurement system according to any one of claims 1-9, characterized in that, It includes the following steps: Set the sweep frequency parameters, collision signal parameters, operating conditions parameters of the automotive power battery pack assembly, and parameters for controlling the automotive power battery pack assembly in the control unit; The control unit switches different test conditions of the automotive power battery pack assembly; The measurement unit first tests the electromagnetic emission of the low-voltage wiring harness of the low-voltage electromagnetic emission measurement unit, and then tests the electromagnetic emission of the high-voltage wiring harness of the high-voltage electromagnetic emission measurement unit; Compare the data obtained for each test condition with the standard data respectively.

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