Charging pile background noise test method and system, and ac power line conducted emission test system

Abstract

Since whether the background noise of the charging pile exceeds the standard is not detected before the AC power line conducted emission test of the vehicle-mounted charger, the AC power line conducted emission index is out of standard due to electromagnetic interference caused by the charging pile noise, and the application provides a charging pile background noise test method, system and AC power line conducted emission test system. The charging pile background noise test system in the anechoic chamber comprises: an alternating current power supply module, a charging connection module, a high-voltage load module, a function control module and a receiver arranged in the anechoic chamber; the alternating current power supply module connects high-voltage power to the high-voltage load module after identifying that the function control module continuously transmits a guide signal within a preset voltage range, and the receiver collects charging pile background noise information formed after the alternating current power supply module connects high-voltage power to the high-voltage load module.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of electromagnetic compatibility of on-board chargers of electric vehicles, and particularly relates to a charging pile background noise testing method, a system and an AC power line conducted emission testing system. BACKGROUND

[0002] An on-board charger (OBC) is one of the key components of an electric vehicle, and its electromagnetic compatibility (EMC) performance is crucial. The ECE R10 standard has clear requirements for the AC power line conducted emission index of the on-board charger, aiming to ensure that it does not produce excessive electromagnetic interference to other devices during operation. With the breakthrough of EMC testing and troubleshooting technology for on-board chargers, engineers have found that the AC power line conducted emission index exceeding the standard is not necessarily caused by the on-board charger itself, but may be caused by the background noise of the charging pile in the anechoic chamber.

[0003] Since the ECE R10 standard does not specify the test method for the background noise of the AC power line conducted emission of electric vehicles, there is an urgent need for a method for testing the background noise of the charging pile in the AC power line conducted emission test of the on-board charger. SUMMARY

[0004] Since the background noise of the charging pile is not detected before the AC power line conducted emission test of the on-board charger, the AC power line conducted emission index exceeds the standard due to the electromagnetic interference caused by the charging pile noise. The application provides a charging pile background noise testing method, a system and an AC power line conducted emission testing system.

[0005] The technical scheme of the application is as follows:

[0006] The application provides a charging pile background noise testing system in an anechoic chamber, comprising:

[0007] An AC power supply module, a charging connection module, a high-voltage load module and a function control module are arranged in the anechoic chamber, and a receiver is arranged outside the anechoic chamber;

[0008] The AC power supply module, the charging connection module and the high-voltage load module are connected in sequence through an AC power line, and the AC power supply module, the charging connection module, the high-voltage load module and the function control module are connected in sequence through a guide line, and the receiver is connected to an artificial power supply network of the AC power supply module;

[0009] The AC power module connects high-voltage power for the high-voltage load module after identifying that the function control module continuously transmits the guide signal within the preset voltage range, and the receiver collects the charging pile background noise information formed after the AC power module connects high-voltage power for the high-voltage load module.

[0010] Preferably, the high-voltage load module comprises a charging socket, a power resistor and a cooling fan, the cooling fan is used for cooling the power resistor, the AC power module, the charging connection module, the charging socket and the power resistor are connected in sequence through an AC power line, and the AC power module, the charging connection module, the charging socket and the function control module are connected in sequence through a guide line.

[0011] Preferably, the AC power module comprises an AC power grid, a charging pile and an artificial power network.

[0012] The input end of the charging pile is connected to the AC power grid through an AC power line, the output end of the charging pile is connected to the input end of the artificial power network through an AC power line, and the output end of the artificial power network is connected to the input end of the receiver through an optical fiber line.

[0013] Preferably, the charging pile comprises a power supply control device and a first control circuit; the first control circuit comprises a first switch and a first load resistor.

[0014] When the charging connection module is completely connected with the AC power module and the high-voltage load module, one end of the first switch is connected to the first output end of the power supply control device through the guide line; when the charging connection module is not completely connected or not connected with the AC power module and the high-voltage load module, one end of the first switch is connected to the second output end of the power supply control device through the guide line.

[0015] One end of the first load resistor is connected to the other end of the first switch through the guide line, and the other end is connected to the guide line of the charging connection module.

[0016] Preferably, the function control module comprises a guide circuit; the guide circuit comprises a diode, a first voltage dividing resistor, a second voltage dividing resistor and a second switch.

[0017] One end of the diode is connected to the guide line of the high-voltage load module, one end of the first voltage dividing resistor and one end of the second voltage dividing resistor are connected to the other end of the diode, the other end of the first voltage dividing resistor is connected to the second switch, and the other end of the second switch and the other end of the second voltage dividing resistor are grounded.

[0018] Preferably, the AC power module, the charging connection module, the high-voltage load module and the function control module are further connected in sequence through a connection confirmation line.

[0019] Preferably, the charging connection module comprises a first connection confirmation circuit, the first connection confirmation circuit comprising a third switch, a third voltage dividing resistor and an RC resistor, a first end of the third switch and one end of the third voltage dividing resistor being connected to a ground wire of the AC power line, the other end of the third voltage dividing resistor being connected to one end of the RC resistor, the other end of the third switch being connected to one end of the RC resistor, and the other end of the RC resistor being connected to the connection confirmation wire of the AC power module and the connection confirmation wire of the high-voltage load module.

[0020] The application also provides a charging pile background noise testing method in an anechoic chamber, and the charging pile background noise testing method in the anechoic chamber comprises the following steps of:

[0021] According to the preset current and the preset voltage, the load requirement of the high-voltage load module is set;

[0022] The functional control module sends a control guide signal in the preset voltage range to the AC power module, so that the AC power module supplies high-voltage power to the high-voltage load module;

[0023] After the high-voltage load module is connected to the high-voltage power, the real-time current and the real-time voltage transmitted on the AC power line and the guide signal on the guide line are detected;

[0024] If the real-time current meets the preset current requirement, the real-time voltage meets the preset voltage requirement, and the collected guide signal is complete, whether the charging pile background noise meets the AC power line conducted emission test requirement of the vehicle-mounted charging machine is identified according to the charging pile background noise collected by the receiver;

[0025] Preferably, the AC power line conducted emission test of the vehicle-mounted charging machine is performed on a whole vehicle carrying the vehicle-mounted charging machine to be tested, the charging voltage corresponding to the worst AC power line conducted emission index is determined as the preset voltage, and the charging current corresponding to the worst AC power line conducted emission index is determined as the preset current.

[0026] The application also provides an AC power line conducted emission test system of a vehicle-mounted charging machine, comprising:

[0027] The vehicle-mounted charging machine to be tested in the whole vehicle state or the bench state, the AC power module, the charging connection module, the receiver and the charging pile background noise suppression device are arranged in the anechoic chamber.

[0028] The AC power module, the charging connection module and the high voltage module of the to-be-tested vehicle-mounted charger are connected in sequence through an AC power line, the AC power module, the charging pile background noise suppression device, the charging connection module and the vehicle-mounted control device of the to-be-tested vehicle-mounted charger are connected in sequence through a guide line, and the receiver accesses an artificial power network of the AC power module; and the charging pile background noise suppression device is arranged on the side closer to the AC power module.

[0029] After the AC power module identifies that the vehicle-mounted control device of the to-be-tested vehicle-mounted charger continuously transmits the guide signal within the preset voltage range, the AC power module accesses high voltage for the to-be-tested vehicle-mounted charger, and the receiver collects electromagnetic interference information formed after the AC power module accesses high voltage for the to-be-tested vehicle-mounted charger.

[0030] The charging pile background noise suppression device is additionally arranged after it is determined that the charging pile background noise does not meet the AC power line conducted emission test requirement of the vehicle-mounted charger according to the charging pile background noise test method in the anechoic chamber.

[0031] Preferably, the charging pile background noise suppression device is an impedance stabilization network or an RC filter circuit board.

[0032] The present application has the following beneficial effects:

[0033] Through the charging pile background noise test system in the anechoic chamber, it can be realized that before the AC power line conducted emission test of the vehicle-mounted charger is performed, it is detected whether the background noise of the charging pile meets the 6dB margin specified in the CISPR16-2-1 in the appendix 13 test basis of ECE.R10 standard, and after it is confirmed that the background noise of the charging pile meets the relevant requirements, the AC power line conducted emission test of the vehicle-mounted charger is performed, so as to avoid the problem that the background noise of the charging pile causes the AC power line conducted emission test of the vehicle-mounted charger to fail. By determining the amount of AC power line conducted emission of the charging pile background noise, the test method of some detection institutions and test customers is agreed, the time of the two parties is reduced, the background noise test efficiency, accuracy and test equipment cost are improved. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is a schematic diagram of an existing AC power line conducted emission test system of a vehicle-mounted charger;

[0035] Figure 2 It is a schematic diagram of an existing AC power line conducted emission test system of a vehicle-mounted charger;

[0036] Figure 3 It is a schematic diagram of an existing AC power line conducted emission test system of a vehicle-mounted charger;

[0037] Figure 4A schematic diagram of a charging pile background noise test system in an anechoic chamber in an embodiment of the present application;

[0038] Figure 5 A flowchart of a charging pile background noise test method in an anechoic chamber in an embodiment of the present application;

[0039] Figure 6 A schematic diagram of an AC power line conducted emission test system of an on-board charger in an embodiment of the present application;

[0040] Figure 7 A charging pile background noise test result graph of a charging pile background noise test system in an anechoic chamber in an embodiment of the present application;

[0041] Figure 8 A charging pile background noise test result graph of a charging pile background noise test system in an anechoic chamber in an embodiment of the present application;

[0042] Figure 9 A charging pile background noise test result graph of a charging pile background noise test system in an anechoic chamber in an embodiment of the present application. DETAILED DESCRIPTION

[0043] In order to facilitate the understanding of those skilled in the art, the present patent will be further described and explained below by means of the accompanying drawings. The description is relatively detailed, but should not be understood as limiting the scope of the present patent. The obvious modifications and substitutions of the following examples are all within the protection scope of the present patent.

[0044] Based on the discussion of the background art, it is known that there is no clear requirement for AC power line conducted emission background noise test of electric vehicles in the ECE R10 standard. Those skilled in the art cannot find technical inspiration from the prior art that charging pile noise causes AC power line conducted emission to exceed the standard.

[0045] Engineers of vehicle manufacturers and testing institutions initially believed that the reason for the AC power line conducted emission exceeding the standard was a problem with the on-board charger itself. The main reason for this inertial thinking of engineers is that: on the one hand, due to the traditional non-charging test, only the test equipment and the device under test need to be connected, without the need to introduce the power supply in the anechoic chamber, which leads engineers to ignore the potential influence of external equipment (such as charging piles) on the device under test; on the other hand, engineers of vehicle manufacturers and testing institutions believe, based on experience, that for on-board chargers that do not pass the AC power line conducted emission test, only need to add filter devices (such as Figure 1 ) at the end of the on-board charger, which can solve the problem of AC power line conducted emission exceeding the standard. Therefore, engineers of vehicle manufacturers and testing institutions habitually attribute the problem to the on-board charger product end.

[0046] However, the supplier of the on-board charger believes that the above problems are not caused by its products, because after decoupling test of the electrical drive assembly integrated with the on-board charger, it is found that the measured result of the conducted emission of the on-board charger still exceeds the standard.

[0047] Finally, engineers point out the source of the excessive AC power line conducted emission to the testing agency.

[0048] When locating the emission source at the testing agency, engineers first remove the on-board charger from the vehicle and install it on a test bench, as shown in Figure 2 At this time, the CP line is led out from the charging pile, enters the charging gun, and is connected to the charging socket connected to the on-board charger. According to this connection mode, the AC power line conducted emission index still exceeds the standard.

[0049] Further, engineers find that when the CP line is directly led out from the charging pile and directly connected to the on-board charger at a distance from the charging gun (i.e., the connection mode is changed from Figure 2 to Figure 3 ), the excessive frequency band data of the AC power line conducted emission index of the on-board charger becomes qualified. Based on the above analysis, engineers finally conclude that the reason for the excessive AC power line conducted emission of the on-board charger is not from the on-board charger itself, but the interference signal on the CP line of the charging pile is transmitted to the L line or N line of the charging gun through electromagnetic coupling, and then propagates along the L line or N line to the artificial power network (AMN), and finally is detected by the receiver 6.

[0050] Therefore, there is an urgent need for a charging pile background noise test method for the AC power line conducted emission of the on-board charger. When the charging pile background noise in the anechoic chamber meets the 6dB margin specified in ECE.R10 Appendix 13 Test Basis CISPR16-2-1, the AC power line conducted emission test verification of the on-board charger can be started.

[0051] Referring to Figure 4 , the embodiment of the present application provides a charging pile background noise test system in an anechoic chamber, which comprises an alternating current power supply module 2, a charging connection module 3, a high-voltage load module 4 and a function control module 5 arranged in an anechoic chamber 1, and a receiver 6 arranged outside the anechoic chamber 1.

[0052] The anechoic chamber 1 usually uses a metal grid and conductive material to cover the surface of the entire room to shield external electric and magnetic fields, so as to ensure the accuracy and reliability of the test results of the on-board charger.

[0053] As Figure 4The AC power module 2, the charging connection module 3 and the high-voltage load module 4 are connected in sequence through the AC power line, the AC power module 2, the charging connection module 3, the high-voltage load module 4 and the function control module 5 are connected in sequence through the guide line, and the receiver 6 is connected to the artificial power network of the AC power module 2.

[0054] After the AC power supply module 2 recognizes that the function control module 5 continuously transmits the guidance signal within the preset voltage range, it connects high voltage power to the high voltage load module 4, and the receiver 6 collects the charging pile background noise information generated after the AC power supply module 2 connects high voltage power to the high voltage load module 4.

[0055] The charging pile background noise test system in the anechoic chamber can be used to test whether the background noise of the charging pile 22 meets the 6dB margin specified in Appendix 13 of the ECE.R10 standard and CISPR16-2-1 before conducting the AC power line conducted emission test on the on-board charger. Only after confirming that the background noise of the charging pile 22 meets the relevant requirements can the on-board charger be tested for AC power line conducted emission. This avoids the problem of the on-board charger failing the AC power line conducted emission test due to the background noise of the charging pile.

[0056] Reference Figure 4 The high-voltage load module 4 includes a charging socket 41, a power resistor 43, and a cooling fan 42. The cooling fan 42 dissipates heat from the power resistor 43. The input end of the power resistor 43 is connected to the AC power cord of the charging socket 41. The AC power supply module 2, the charging connection module 3, the charging socket 41, and the power resistor 43 are sequentially connected via the AC power cord. The AC power supply module 2, the charging connection module 3, the charging socket 41, and the power resistor 43 are sequentially connected via guide wires. Specifically, the cooling fan 42 is placed directly in front of the power resistor 43.

[0057] Reference Figure 4 The AC power supply module 2 includes an AC power grid 21, a charging pile 22 and an artificial power network 23; the input end of the charging pile 22 is connected to the AC power grid 21 through an AC power line, and the output end is connected to the input end of the artificial power network 23 through an AC power line, and the output end of the artificial power network 23 is connected to the input end of the receiver 6 through an optical fiber line.

[0058] The AC grid 21 is, for example, a household electrical grid, and has a voltage of, for example, 220V. The AC grid 21 is electrically connected to the charging station 22 via a power cable, and the charging station 22 is electrically connected to the artificial mains network 23 via a power cable. The artificial mains network (AMN) 103 is widely used in testing various types of power equipment.

[0059] ReferenceFigure 4 The charging pile 22 comprises a power supply control device 221 and a first control circuit; the first control circuit comprises a first switch S1 and a first load resistor R1; when the charging connection module 3 is completely connected with the alternating current power supply module 2 and the high-voltage load module 4, one end of the first switch S1 is connected to the first output end of the power supply control device 221 through a guide line; when the charging connection module 3 is not completely connected or not connected with the alternating current power supply module 2 and the high-voltage load module 4, one end of the first switch S1 is connected to the second output end of the power supply control device 221 through a guide line; one end of the first load resistor R1 is connected to the other end of the first switch S1 through a guide line, and the other end is connected to the guide line of the charging connection module 3.

[0060] The charging connection module 3 comprises a charging gun, one side of the charging gun is provided with a charging plug for being connected with the charging socket 41 of the high-voltage load module 4 through an AC power line, a guide line and a connection confirmation line, and the other side is responsible for being connected with the artificial power network 23AMN through an AC power line and being connected through a guide line and a connection confirmation line.

[0061] In this embodiment, the function control module 5 comprises a guide circuit; the guide circuit comprises a diode D1, a first voltage dividing resistor R2, a second voltage dividing resistor R3 and a second switch S2; one end of the diode D1 is connected to the guide line in the charging socket 41 of the high-voltage load module 4, one end of the first voltage dividing resistor R2 and one end of the second voltage dividing resistor R3 are connected to the other end of the diode D1, the other end of the first voltage dividing resistor R2 is connected to the second switch S2, and the other end of the second switch S2 and the other end of the second voltage dividing resistor R3 are grounded.

[0062] According to the national standard GB / T 18487.1-2023, when the charging connection module 3 is not completely connected with the alternating current power supply module 2 and the high-voltage load module 4, the voltage detected by the power supply control device 221 is 12V; after the charging connection module 3 is completely connected with the alternating current power supply module 2 and the high-voltage load module 4, the voltage detected by the power supply control device 221 becomes 9V under the voltage division of the first load resistor R1 and the second voltage dividing resistor R3; at this time, the power supply control device 221 switches the first switch S1 from the 12V connection state to the PWM connection state. After that, when the second switch S2 is closed, the first voltage dividing resistor R2 is connected to the circuit, and the voltage detected by the power supply control device 221 changes from 9VPWM to 6VPWM; at this time, the power supply control device 221 can control the high-voltage switches K1 and K2 in the power resistor 43 to be closed, so as to realize the power supply of the power resistor 43. That is, the preset voltage range in the embodiment of the application can be understood as 6VPWM. Figure 4

[0063] Regarding the control of the second switch S2, the second switch S2 is closed by the tester when the charging pile background noise test is performed. ​

[0064] In combination Figure 4 In the embodiments of the present application, the AC power module 2, the charging connection module 3, the high-voltage load module 4 and the function control module 5 are also connected in sequence through the connection confirmation line.

[0065] The charging connection module 3 comprises a first connection confirmation circuit, which comprises a third switch S3, a third voltage dividing resistor R4 and an RC resistor. The first end of the third switch S3 and one end of the third voltage dividing resistor R4 are connected to the ground of the AC power line. The other end of the third voltage dividing resistor R4 is connected to one end of the RC resistor. The other end of the third switch S3 is connected to one end of the RC resistor. The other end of the RC resistor is connected to the connection confirmation line of the AC power module 2 and the connection confirmation line in the charging socket 41 of the high-voltage load module 4.

[0066] In combination Figure 5 By means of the third voltage dividing resistor R4 and the second load resistor R5 and the third load resistor R6 in the function control module 5, the maximum charging current capacity on the AC power line can be detected.

[0067] In the embodiments of the present application, the RC resistor of the charging gun and the third voltage dividing resistor R4 have different values based on different current charging guns. The duty cycle and resistance value corresponding to the maximum charging current 63A allowed by the charging pile 22 and the high-voltage cable can be selected for the guide line and the connection confirmation line. Thus, the charging pile background noise can cover multiple scenarios such as 8A, 16A and 32A.

[0068] Referring to Figure 7 The present application also provides a charging pile background noise test method in an anechoic chamber, which is applied to the test system for electromagnetic interference of the vehicle-mounted charging machine. The charging pile background noise test method in the anechoic chamber is performed before the AC power line conducted emission test method of the vehicle-mounted charging machine. The charging pile background noise test method in the anechoic chamber comprises the following steps.

[0069] S101, setting the load demand of the high-voltage load module 4 according to a preset current and a preset voltage;

[0070] S102, sending a control guide signal in a preset voltage range to the AC power module 2 through the function control module 5, so that the AC power module 2 supplies high-voltage power to the high-voltage load module 4;

[0071] S103, detecting the real-time current and real-time voltage transmitted on the AC power line and the guide signal on the guide line after the high-voltage load module 4 is connected to the high-voltage power;

[0072] S104, if the real-time current meets the preset current requirement, the real-time voltage meets the preset voltage requirement, and the collected pilot signal is complete, then according to the charging pile background noise collected by the receiver 6, whether the charging pile background noise meets the AC power line conducted emission test requirement of the on-board charger is identified.

[0073] The AC power line conducted emission test of the on-board charger is performed on the whole vehicle carrying the on-board charger to be tested in advance, the charging voltage corresponding to the worst AC power line conducted emission index obtained is determined as the preset voltage, and the charging current corresponding to the worst AC power line conducted emission index obtained is determined as the preset current.

[0074] The on-board charger under different SOC (battery state of charge) is tested for AC power line conducted emission in the whole vehicle environment, and the voltage and current conditions of the on-board charger under the most severe working condition are determined as the standard reference index for subsequent tests. During the test, the SOC of the whole vehicle is set to multiple key points (for example, 10%, 20%, 30%, 50%, 80%, etc.), covering typical use scenarios from low power to high power; at each SOC point, the charging pile 22 is started and charging is started, the voltage and current values of the L / N line are measured using a multimeter and an ammeter, and the conducted emission index of the on-board charger is tested according to the standard frequency band (such as 150 kHz to 30 MHz) using an EMI receiver 6. Finally, by analyzing the conducted emission performance at different SOC points, the SOC point that makes the conducted emission index of the on-board charger worst is determined. The L / N line voltage value corresponding to the worst conducted emission index is selected as the preset voltage, and the L / N line current value corresponding to the worst conducted emission index is selected as the preset current.

[0075] The specific implementation steps of the charging pile background noise test method in the anechoic chamber are as follows:

[0076] S201, turn on the cooling fan 42, and swipe the charging pile 22.

[0077] S202, after about 3s, manually close the second switch S2.

[0078] S203, use a multimeter to collect the L line voltage and N line voltage of the AC power line, and use an ammeter to collect the L line current and N line current of the AC power line.

[0079] S204, if the L line voltage and N line voltage both meet the corresponding preset voltage requirement and the L line current and N line current both meet the corresponding preset current requirement, then use an oscilloscope to collect the CP signal; if the L line voltage and N line voltage both do not meet the corresponding preset voltage requirement and / or the L line current and N line current both do not meet the corresponding preset current requirement, then adjust the parameters of the power resistor 43, and repeat steps S201-S204.

[0080] The power resistor 43 is typically adjusted by changing its resistance, thereby affecting the output power of the charging station 22. The specific adjustment method is as follows: Based on the preset voltage V and the preset current I, calculate the target power P: P = V × I. For example, if the preset voltage is 220V and the preset current is 16A, the target power is: P = 220V × 16A = 3520W. The resistance R of the power resistor 43 can be calculated using the following formula: R = V / I. For example, if the preset voltage is 220V and the preset current is 16A, then: R = 220V / 16A = 13.75Ω.

[0081] If the current is too high, the resistance of the power resistor 43 needs to be increased to reduce the current; if the current is too low, the resistance of the power resistor 43 needs to be reduced to increase the current.

[0082] Based on the calculated resistance value, gradually adjust the parameters of the power resistor 43. After each adjustment, re-measure the voltage and current of the L line and the N line to observe the changes.

[0083] After each adjustment, re-measure the voltage and current of the L and N lines to ensure that they meet the target reference indicators: if the voltage and current of the L and N lines both meet their respective target values, the adjustment is completed.

[0084] S205: If the CP signal is intact, use receiver 6 to test the charging pile background noise transmitted through the AC power line.

[0085] S206. If the background noise in the electromagnetic compatibility test chamber meets the 6 dB margin in step 205, the on-board charger AC power line conducted emission test verification can be started. Otherwise, add a corresponding ISN (impedance stabilization network) 11 or RC filter circuit board on the side of the CP line close to the charging pile 22. If the background noise in the electromagnetic compatibility test chamber meets the 6 dB margin, the on-board charger AC power line conducted emission test verification can be started.

[0086] like Figure 6 As shown, when the charging pile background noise does not meet the AC power line conducted emission test requirements of the on-board charger according to the above-mentioned charging pile background noise test method in the anechoic chamber, the measured average value of the charging pile background noise is very close to the conducted average value target in the low frequency band.

[0087] Reference Figure 8 The present application also provides an AC power line conducted emission test system for a vehicle charger, including:

[0088] The on-board charger 7 to be tested, the AC power module 2, the charging connection module 3, the receiver 6 and the charging pile background noise suppression device are set in the anechoic chamber 1 in the complete vehicle state or the test bench state;

[0089] The AC power module 2, the charging connection module 3, and the high-voltage module 71 of the on-board charger 7 to be tested are connected in sequence via an AC power line. The AC power module 2, the charging pile background noise suppression device, the charging connection module 3, and the on-board control device of the on-board charger 7 to be tested are connected in sequence via a guide line. The receiver 6 is connected to the artificial power network of the AC power module 2. The charging pile background noise suppression device is located on the side closer to the AC power module 2.

[0090] After the AC power module 2 recognizes that the onboard control device of the onboard charger 7 under test continuously transmits a pilot signal within a preset voltage range, it connects high voltage power to the onboard charger 7 under test. The receiver 6 collects electromagnetic interference information generated by the AC power module 2 connecting the onboard charger 7 under test to the high voltage power.

[0091] Among them, the charging pile background noise suppression device is added after it is determined that the charging pile background noise does not meet the AC power line conducted emission test requirements of the on-board charger according to the charging pile background noise test method in the above-mentioned anechoic chamber.

[0092] The background noise suppression device of the charging pile is an impedance stabilization network ISN8 or an RC filter circuit board.

[0093] like Figure 9 As shown in the figure, when the charging pile background noise does not meet the AC power line conducted emission test requirements of the on-board charger according to the above-mentioned charging pile background noise test method in the anechoic chamber, if the impedance stabilization network ISN8 is set near the power resistor end, the measured average value of the charging pile background noise in the low frequency band is still very close to the conducted average target.

[0094] like ​ As shown in the figure, when the charging pile background noise does not meet the AC power line conducted emission test requirements of the on-board charger according to the above-mentioned charging pile background noise test method in the anechoic chamber, if an impedance stabilization network ISN8 is installed near the charging pile end, the difference between the measured average value of the charging pile background noise and the conducted average target value exceeds 6dB margin in both the low and high frequency bands. It can be seen that adding an impedance stabilization network ISN8 or an RC filter circuit board near the charging pile end is an effective means to solve the charging pile background noise problem.

[0095] The AC power line conduction emission test system of the on-board charger in the embodiment of the present application does not need to add a shielding layer to the CP harness when processing the guide signal emission, nor does it need to place the CP signal source and the photoelectric conversion circuit outside the darkroom (the frequency of the CP signal KHz is objectively not enough to cause radiation emission, and mainly affects the conduction coupling background noise). Only an impedance stabilization network ISN8 or an RC filter circuit board is matched between the charging pile 22 and the charging gun, which reduces the workload of arranging additional arrangements and improves work efficiency.

[0096] It should be noted that each of the embodiments in the present specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be mutually referred to.

[0097] Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art can make further changes and modifications to the embodiments once they know the basic inventive concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0098] It should also be noted that in this paper, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the orientation or positional relationship shown in the drawings, which is for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or component referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, relationship terms such as "first" and "second" are used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations, nor can it be understood as indicating or implying relative importance. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or terminal device including a series of elements does not include those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or terminal device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or terminal device including the element.

[0099] The above describes the technical solutions provided by the present application in detail. The principles and implementation manners of the present application are described by applying specific examples in this paper. The above description of the embodiments is only for the purpose of helping to understand the present application, and the content of the specification should not be understood as a limitation on the present application. Meanwhile, for those skilled in the art, according to the present application, there will be different forms of changes in specific implementation manners and application ranges, which do not need to be enumerated here, and it is impossible to enumerate all the implementation manners, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A method for testing background noise of a charging pile in an anechoic chamber, applied to a charging pile background noise testing system in an anechoic chamber, characterized in that, The charging pile background noise test system in the anechoic chamber comprises: The AC power supply module (2), the charging connection module (3), the high-voltage load module (4) and the function control module (5) are arranged in the anechoic chamber (1), and the receiver (6) is arranged outside the anechoic chamber (1); The AC power supply module (2), the charging connection module (3) and the high-voltage load module (4) are connected in sequence through the AC power supply line, the AC power supply module (2), the charging connection module (3), the high-voltage load module (4) and the function control module (5) are connected in sequence through the guide line, and the receiver (6) is connected to the artificial power supply network of the AC power supply module (2); After the AC power supply module (2) identifies that the function control module (5) continuously transmits the guide signal in the preset voltage range, the high-voltage load module (4) is connected to high-voltage power supply, and the receiver (6) collects the charging pile background noise information formed after the AC power supply module (2) connects the high-voltage load module (4) to high-voltage power supply. The charging pile background noise test method in the anechoic chamber comprises: According to the preset current and the preset voltage, the load requirement of the high-voltage load module (4) is set; The function control module (5) sends a control guide signal in the preset voltage range to the AC power supply module (2), so that the AC power supply module (2) connects the high-voltage load module (4) to high-voltage power supply; After the high-voltage load module (4) is connected to high-voltage power supply, the real-time current and real-time voltage transmitted on the AC power supply line and the guide signal on the guide line are detected; If the real-time current meets the preset current requirement, the real-time voltage meets the preset voltage requirement, and the collected guide signal is complete, whether the charging pile background noise meets the AC power supply line conducted emission test requirement of the vehicle-mounted charger is identified according to the charging pile background noise collected by the receiver (6); The worst charging voltage corresponding to the obtained AC power supply line conducted emission index is determined as the preset voltage, and the worst charging current corresponding to the obtained AC power supply line conducted emission index is determined as the preset current.

2. The method of claim 1, wherein, The high-voltage load module (4) comprises a charging socket (41), a power resistor (43) and a cooling fan (42), the cooling fan (42) is used for cooling the power resistor (43), the AC power supply module (2), the charging connection module (3), the charging socket (41) and the power resistor (43) are connected in sequence through the AC power supply line, and the AC power supply module (2), the charging connection module (3), the charging socket (41) and the function control module (5) are connected in sequence through the guide line.

3. The method of claim 1, wherein the charging station background noise test is performed in an anechoic chamber. The AC power supply module (2) comprises an AC power grid (21), a charging pile (22) and an artificial power supply network (23); The input end of the charging pile (22) is connected to the AC power grid (21) through the AC power supply line, the output end of the charging pile (22) is connected to the input end of the artificial power supply network (23) through the AC power supply line, and the output end of the artificial power supply network (23) is connected to the input end of the receiver (6) through the optical fiber line.

4. The method of claim 3, wherein the charging station background noise test in an anechoic chamber is characterized by, The charging pile (22) comprises a power supply control device (221) and a first control circuit; the first control circuit comprises a first switch (S1) and a first load resistor (R1); When the charging connection module (3) is completely connected with the AC power supply module (2) and the high-voltage load module (4), one end of the first switch (S1) is connected to the first output end of the power supply control device (221) through a guide line; when the charging connection module (3) is not completely connected or not connected with the AC power supply module (2) and the high-voltage load module (4), one end of the first switch (S1) is connected to the second output end of the power supply control device (221) through a guide line; One end of the first load resistor (R1) is connected to the other end of the first switch (S1) through a guide line, and the other end is connected to the guide line of the charging connection module (3).

5. The method of claim 4, wherein the charging station background noise test in an anechoic chamber is characterized by, The function control module (5) comprises a guide circuit; the guide circuit comprises a diode (D1), a first voltage dividing resistor (R2), a second voltage dividing resistor (R3) and a second switch (S2); One end of the diode (D1) is connected to the guide line of the high-voltage load module (4), one end of the first voltage dividing resistor (R2) and one end of the second voltage dividing resistor (R3) are connected to the other end of the diode (D1), the other end of the first voltage dividing resistor (R2) is connected to the second switch (S2), and the other end of the second switch (S2) and the other end of the second voltage dividing resistor (R3) are grounded.

6. The method of claim 1, wherein, The AC power supply module (2), the charging connection module (3), the high-voltage load module (4) and the function control module (5) are further connected in sequence through a connection confirmation line.

7. The method of claim 6, wherein the charging station background noise test in an anechoic chamber is characterized by, The charging connection module (3) comprises a first connection confirmation circuit, the first connection confirmation circuit comprises a third switch (S3), a third voltage dividing resistor (R4) and an RC resistor, the first end of the third switch (S3) and one end of the third voltage dividing resistor (R4) are connected to the ground line of the AC power supply line, the other end of the third voltage dividing resistor (R4) is connected to one end of the RC resistor, the other end of the third switch (S3) is connected to one end of the RC resistor, and the other end of the RC resistor is connected to the connection confirmation line of the AC power supply module (2) and the connection confirmation line of the high-voltage load module (4).

8. A vehicle charger AC power line conducted emission test system, characterized in that: Comprise: The vehicle state or bench state to be measured vehicle charger (7), the AC power supply module (2), the charging connection module (3), the receiver (6) and the charging pile background noise suppression device arranged in the anechoic chamber (1); The AC power supply module (2), the charging connection module (3) and the high-voltage module (71) of the to-be-measured vehicle charger (7) are connected in sequence through the AC power supply line, the AC power supply module (2), the charging pile background noise suppression device, the charging connection module (3) and the vehicle control device of the to-be-measured vehicle charger are connected in sequence through the guide line, and the receiver (6) is connected to the artificial power supply network (23) of the AC power supply module (2); and the charging pile background noise suppression device is arranged on the side closer to the AC power supply module (2); After the AC power module (2) recognizes that the onboard control device of the onboard charger (7) to be tested continuously transmits a guide signal within a preset voltage range, the onboard charger (7) to be tested is connected to high voltage electricity, and the receiver (6) collects electromagnetic interference information generated after the AC power module (2) connects the onboard charger (7) to be tested in a complete vehicle state or a test bench state to high voltage electricity; Among them, the charging pile background noise suppression device is added after the charging pile background noise test method in the anechoic chamber according to claim 1 determines that the charging pile background noise does not meet the AC power line conducted emission test requirements of the on-board charger.

9. The on-board charger AC power cord emissions test system of claim 8, wherein, The background noise suppression device of the charging pile is an impedance stabilization network or an RC filter circuit board.

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