CN117590833A

CN117590833A - EMC automatic test system and method of vehicle-mounted electronic control unit

Info

Publication number: CN117590833A
Application number: CN202311644009.1A
Authority: CN
Inventors: 刘永春; 秦涛; 高崧林; 李亚男
Original assignee: China National Heavy Duty Truck Group Jinan Power Co Ltd
Current assignee: China National Heavy Duty Truck Group Jinan Power Co Ltd
Priority date: 2023-12-01
Filing date: 2023-12-01
Publication date: 2024-02-23

Abstract

The invention provides an EMC automatic test system and method of a vehicle-mounted electronic control unit, wherein the system comprises: the vehicle-mounted electronic control unit is in data connection with the EMC load box through a test wire harness, the EMC load box is in data connection with the signal conversion module through an optical fiber, and the signal conversion module is in data connection with the upper computer; the EMC load box is used for communicating with the upper computer through the CAN network and feeding back test data to the upper computer; the test wire harness is connected with the vehicle-mounted electronic control unit to provide signals for the vehicle-mounted electronic control unit and collect signals of test samples; the upper computer is internally provided with upper computer control software, and is used for transmitting an upper computer working condition test instruction to the EMC load box through the built-in optical fiber transceiver, outputting a required signal to the vehicle-mounted electronic control unit through a function board card in the EMC load box, and simultaneously transmitting an acquired signal to the upper computer to be compared with a test standard so as to generate a test result, and displaying the running state of the EMC load box in real time by the upper computer.

Description

EMC automatic test system and method of vehicle-mounted electronic control unit

Technical Field

The invention relates to the technical field of vehicle EMC testing, in particular to an EMC automatic testing system and method of a vehicle-mounted electronic control unit.

Background

EMC (electromagnetic compatibility) is known as Electro Magnetic Compatibility, which is defined as the ability of devices and systems to function properly in their electromagnetic compatible environment without making up an intolerable electromagnetic disturbance to anything in the environment. Including both EMI (Electro magnetic interference ) and EMS (Electro magnetic susceptibility, electromagnetic immunity).

Along with the continuous improvement of the requirements of vehicle electric, intelligent and networking, the vehicle wireless communication system technology and other applications are becoming wider and wider, the control and interface interaction of each electric control module in the vehicle is becoming more and more complex, the complexity of the electromagnetic compatibility environment facing the vehicle is aggravated, the exposed EMC problem is particularly prominent and serious, the functions of the components are affected when the vehicle is light, and the vehicle cannot normally run when the vehicle is heavy. In order to meet the electromagnetic compatibility requirement of the whole vehicle and improve the electromagnetic compatibility of the whole vehicle, a vehicle-mounted electronic control unit (ECU for short) needs to be tested and verified according to the electromagnetic compatibility test standard of the electronic parts of the vehicle so as to ensure whether the electromagnetic compatibility meets the standard requirement. The EMC automatic test system is necessary equipment for an EMC model test and a verification test of products, provides analog input signals such as digital quantity, analog quantity, frequency quantity and the like for the ECU in the EMC test process, provides necessary load acquisition and signal excitation to ensure that the ECU operates in expected working conditions in the EMC test process, simulates the working state of the operation of a real vehicle, monitors the output signals of the ECU and the working state of an actuator in the EMC test process, manages test items and test processes, and records and analyzes test data.

The traditional EMC test system comprises an EMC load box, a signal generating device, optical fiber conversion equipment, a test harness, CAN hardware equipment, an oscilloscope and other test equipment. Before testing, the customized and adaptive load device is required to be used for testing and verifying the special controller according to the resources of the controller. As shown in fig. 1, the storage battery, the EMC load box and the controller are placed in a darkroom or a shielding room, and the oscilloscope, the signal generating device, the computer and the CAN hardware equipment are placed outside the darkroom or the shielding room. The EMC load box is powered by a storage battery and is connected to a power line of the EMC load box; the EMC load box is connected to the tested controller through an EMC test wire harness; the signal generating device is a device capable of generating signals, such as a signal generator or a signal generating module, and the like, required signal parameters are adjusted before the test, and the signal generating device is connected to the EMC load box through optical fibers; the real executor in the EMC load box is connected to an oscilloscope through an optical fiber by a BNC interface of the front panel, and whether the waveform of the signal is abnormal or not is observed; the CAN communication equipment is used for monitoring signal parameters of the controlled controller, the CAN optical fiber converter is connected to a test calibration tool based on a CAN-to-USB interface, and the USB interface is connected with a computer through a USB wire harness, so that functions of ECU program brushing, fault detection, signal monitoring and the like are realized. During EMC test, the EMC performance test of the controller is completed by setting the input signal state on the EMC load box and the signal state of the signal generating device to simulate a certain running condition or a certain specific function of a real vehicle or a component and the like. And (5) monitoring signals through an oscilloscope and the like, and judging whether an abnormal phenomenon exists in the EMC test process.

However, because the EMC load box of the EMC test system is dedicated to the dedicated controller, once the controller is replaced, the interior is required to be greatly changed or re-customized, resulting in waste of time, resources and cost; moreover, the EMC load box is customized and adapted according to the special controller resources, so that the EMC test requirements of different platform controllers cannot be supported, and the universality and the expandability are poor. In addition, in the test process, because different operating conditions need to be manually set, a single operating condition or a specific function of a real vehicle or a part is simulated, and the like, the different operating conditions of the controller cannot be automatically switched in the test process, and the signal parameters are complicated to adjust, so that the test efficiency is low; if parameters need to be monitored and whether abnormal phenomena exist in the EMC test process of each signal is judged, hardware tools such as an oscilloscope or CANoe and the like are required to be externally connected, the functions of test item management, working condition setting, out-of-tolerance alarm and the like cannot be realized, and the degree of automation is low.

Disclosure of Invention

Aiming at the problems, the invention aims to provide an EMC automatic test system and method of a vehicle-mounted electric control unit, which can be suitable for electromagnetic compatibility tests of vehicle-mounted electric control units of different platforms, have universality, do not need to repeatedly customize an EMC load device for controller development of different projects, and reduce product development time and cost.

The invention aims to achieve the aim, and the aim is achieved by the following technical scheme:

in a first aspect, the invention discloses an EMC automatic test system of a vehicle-mounted electronic control unit, comprising: the system comprises a vehicle-mounted electronic control unit, an EMC load box, a signal conversion module and an upper computer; the vehicle-mounted electronic control unit is in data connection with the EMC load box through a test wire harness, the EMC load box is in data connection with the signal conversion module through an optical fiber, and the signal conversion module is in data connection with the upper computer; the EMC load box is used for communicating with the upper computer through the CAN network and feeding back test data to the upper computer; the test wire harness is connected with the vehicle-mounted electronic control unit to provide signals for the vehicle-mounted electronic control unit and collect signals of test samples; the upper computer is internally provided with upper computer control software, and is used for transmitting an upper computer working condition test instruction to the EMC load box through the built-in optical fiber transceiver, outputting a required signal to the vehicle-mounted electronic control unit through a function board card in the EMC load box, and simultaneously transmitting an acquired signal to the upper computer to be compared with a test standard so as to generate a test result, and displaying the running state of the EMC load box in real time by the upper computer.

Further, the signal conversion module includes: a CAN optical fiber converter and a CAN-to-USB converter; the CAN optical fiber converter is respectively connected with the EMC load box and the CAN-to-USB converter in data, and the CAN-to-USB converter is connected with the upper computer in data; the CAN optical fiber converter is used for converting an input CAN signal into an optical signal, converting the optical signal into the CAN signal and outputting the CAN signal; the CAN-to-USB converter is used for converting CAN signals into USB signals so as to realize the communication between the EMC load box and the upper computer; and sending a command corresponding to the working condition mode sent by the upper computer according to the defined actual working condition to the EMC load box so as to control the corresponding output state of the EMC load box, executing corresponding acquisition work and feeding the acquisition information back to the upper computer.

Further, a shielding box body is arranged in the EMC load box, a guide rail is arranged in the shielding box body, and a board card is arranged on the guide rail and comprises a motherboard, a daughter board, a board card connector, a power interface and a data interface; the power interface and the data interface are arranged on the motherboard, the motherboard is connected with the daughter board through the board card connector, and the motherboard is connected with the vehicle-mounted electronic control unit through the data interface; the board card connector is provided with a plurality of clamping grooves for connecting the sub-boards, each clamping groove is provided with a unique address, and when the sub-boards are connected with the clamping grooves, the sub-boards acquire corresponding clamping groove addresses and add the corresponding clamping groove addresses to the interactive CAN information; and the mother board is used for acquiring the CAN information of each daughter board, and uploading the CAN information to the upper computer after the CAN information is summarized.

Further, a filter module is arranged in the EMC load box; and the filtering module is used for carrying out filtering treatment on all the wires entering and exiting the EMC load box so as to filter interference signals coupled on the wires.

Further, the filtering module includes: a power filter and a harness filter; the power filter is arranged in a preset independent space in the EMC load box, and the preset independent space is arranged at a power inlet of the EMC load box; the harness filter is positioned along the wires into and out of the EMC load box to absorb and transmit the interference signals coupled on the wires.

Further, an address identification line, a power supply line and a communication line are arranged in the board card connector; the address identification lines are 4 and are used for representing a 4-bit card slot address according to signals of high and low level strokes, when the sub-card is connected with the card slot, a singlechip of the sub-card determines own address through the high and low levels of the 4 address identification lines, and a software message configuration interface determines the source and the sending position of a message through the address.

Further, the system also comprises a storage battery, and the storage battery is electrically connected with the power interface through a power line.

Further, the EMC load box is provided with a clamp Ma Jiaolun and a binding post; the Fuma foot wheels are arranged at the bottom of the EMC load box and used for moving the box body; the binding post is grounded through a connecting copper net.

In a second aspect, the invention also discloses an automatic EMC test method of the vehicle-mounted electronic control unit, the method adopts the automatic EMC test system of the vehicle-mounted electronic control unit, and the method comprises the following steps:

determining the input and output states of the vehicle-mounted electronic control unit;

when the vehicle-mounted electronic control unit is in an input state, the upper computer determines the output of an EMC load box hardware channel through a CAN protocol command;

the vehicle-mounted electronic control unit generates a corresponding feedback signal after acquiring the output of the corresponding channel, and uploads the feedback signal to the upper computer through a CAN protocol;

the upper computer determines a test result by comparing the feedback signal with a corresponding preset value.

Further, the method further comprises:

when the vehicle-mounted electronic control unit is in an output state, the upper computer sends output parameters to the vehicle-mounted electronic control unit through a CAN protocol;

the vehicle-mounted electronic control unit outputs a hardware channel according to the control parameters;

and comparing the hardware driving parameters acquired by the upper computer with the corresponding set values so as to determine a test result.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention is suitable for electromagnetic compatibility testing of vehicle-mounted electronic control units of different platforms, has universality, does not need to repeatedly customize an adaptive EMC load box for controller development of different projects, and reduces product development time and cost. Meanwhile, the electromagnetic radiation level of the whole EMC load box is greatly reduced due to the design of the filtering module of the EMC load box, the shielding requirement is reduced, and the cost is reduced.

2. The EMC load box of the invention connects the resources to the vehicle-mounted electric control unit uniformly through the motherboard, and matches different vehicle-mounted electric control units through changing and combining different daughter boards, and the motherboard and the daughter boards adopt standard 4-bit address identification lines, power supply lines and CAN communication lines in an interactive way. The same EMC test system can be adopted for EMC tests of the vehicle-mounted electronic control units of different platforms, so that resource waste is avoided. The ECU test of different platforms can be satisfied through changing different EMC test pencil switches.

3. The EMC automatic test system disclosed by the invention can be interconnected, can be controlled and monitored by the same upper computer, and realizes that one EMC test system supports the testing of a plurality of ECUs by selecting the corresponding address board card through the ECU resource allocation.

4. The invention fixes the board card on the guide rail of the inner box of the shielding box, can match ECUs of different platforms by replacing and combining different sub boards, and simultaneously facilitates the function expansion and the maintenance replacement, and reduces the maintenance cost.

5. According to the invention, different test working conditions CAN be automatically switched in the ECU test process, manual setting is not needed, the upper computer control software flexibly configures PWM input and output of the load device through CAN information, flexibly configures switching value input, analog quantity input and frequency quantity input, configures the working state of the monitoring output actuator, and realizes the automation of an EMC test system.

6. The invention adopts the filter module and the EMC load box adopts a double-layer shielding structure, thereby ensuring the stability of the test. The interface type can be automatically adjusted through program configuration, so that the universality and the economy of the subsequent EMC test are realized.

It can be seen that the present invention has outstanding substantial features and significant advances over the prior art, as well as the benefits of its implementation.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

Fig. 1 is a system configuration diagram of an EMC test system according to the background of the invention.

Fig. 2 is a system configuration diagram of an embodiment of the present invention.

Fig. 3 is a schematic view of a board card according to an embodiment of the invention.

Fig. 4 is a flow chart of a method of an embodiment of the present invention.

Detailed Description

In order to better understand the aspects of the present invention, the present invention will be described in further detail with reference to the accompanying drawings and detailed description. It will be apparent that the described embodiments are only some, but not all, embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Referring to fig. 2, this embodiment provides an EMC automatic test system of a vehicle-mounted electronic control unit, including: the system comprises a vehicle-mounted electronic control unit, an EMC load box, a signal conversion module, an upper computer and a storage battery. The vehicle-mounted electric control unit is in data connection with the EMC load box through a test wire harness, the EMC load box is in data connection with the signal conversion module through an optical fiber, the signal conversion module is in data connection with the upper computer, and the storage battery is electrically connected with the EMC load box through a power line.

The EMC load box is used for communicating with the upper computer through the CAN network and feeding back test data to the upper computer; the test harness is connected with the vehicle-mounted electronic control unit, and signals are provided for the vehicle-mounted electronic control unit and signals of the test sample are collected.

In a specific embodiment, the EMC load box is an important component of the whole test system, and is communicated with the upper computer through a CAN network to feed back test data to the upper computer, and is connected with the ECU through a test wire harness to provide signals for the ECU and collect signals of test samples, and the signals are connected with each other through the CAN network.

The upper computer is internally provided with upper computer control software, and is used for transmitting an upper computer working condition test instruction to the EMC load box through the built-in optical fiber transceiver, outputting a required signal to the vehicle-mounted electronic control unit through a function board card in the EMC load box, and simultaneously transmitting an acquired signal to the upper computer to be compared with a test standard so as to generate a test result, and displaying the running state of the EMC load box in real time by the upper computer.

In a specific embodiment, the upper computer control software realizes automatic acquisition, identification, display and recording software. The upper computer working condition test instruction is transmitted to the EMC load box through the optical fiber transceiver, all function board cards in the EMC load box output required signals to the ECU through aviation plug, meanwhile, the data acquisition card transmits the acquired signals to the upper computer to be compared with the test standard, the upper computer displays the running state of the EMC load box in real time, and meanwhile, relevant data are stored for checking, analyzing and printing. The upper computer supports ECU tests of different electric control system platforms, the upper computer can set corresponding test strategies, the generated configuration files are managed by Excel files, and the ECU tests of different platforms are met by replacing corresponding EMC test harness switches.

In a specific embodiment, the signal conversion module includes: a CAN optical fiber converter and a CAN-to-USB converter; the CAN optical fiber converter is respectively connected with the EMC load box and the CAN-to-USB converter in a data way, and the CAN-to-USB converter is connected with the upper computer in a data way.

The CAN optical fiber converter is used for converting an input CAN signal into an optical signal and converting the optical signal into the CAN signal, so that electromagnetic radiation caused by CAN communication between the upper computer and the EMC load box CAN be prevented from affecting the EMC test of the controller.

The CAN-to-USB converter is used for converting CAN signals into USB signals so as to realize the communication between the EMC load box and the upper computer; and sending a command corresponding to the working condition mode sent by the upper computer according to the defined actual working condition to the EMC load box so as to control the corresponding output state of the EMC load box, executing corresponding acquisition work and feeding the acquisition information back to the upper computer. Therefore, the CAN-to-USB converter CAN be used for realizing communication between the EMC load box and the upper computer, the upper computer software sends a corresponding working condition mode to the lower computer according to defined actual working conditions, controls the corresponding output state of the load box according to a command read by the bus, executes corresponding acquisition work and feeds back an acquisition result to the upper computer through the bus.

In addition, the test wire harness is used for connecting the EMC load box and the vehicle-mounted electric control unit, the EMC load box outputs required input signals to the vehicle-mounted electric control unit through the test wire harness, the vehicle-mounted electric control unit outputs signals to drive corresponding loads in the EMC load box through the test wire harness, the vehicle-mounted electric control unit and the EMC load box communicate through CAN twisted pairs in the test wire harness, and the EMC load box forwards control commands sent by an upper computer to the vehicle-mounted electric control unit through a CAN bus and receives feedback messages of the vehicle-mounted electric control unit.

In a specific embodiment, a shielding box body is arranged in the EMC load box, a guide rail is arranged in the shielding box body, and a board card is arranged on the guide rail. As shown in fig. 3, the board card includes a motherboard 1, a daughter board 2, a board card connector 3, a power interface 4, and a data interface 5; the power interface 4 and the data interface 5 are arranged on the motherboard 1, the motherboard 1 is connected with the daughter board 2 through the board card connector 3, the motherboard 1 is connected with the vehicle-mounted electric control unit through the data interface 5, and the motherboard 1 is connected with the storage battery through the power interface 4. Wherein, the daughter board 2 has a plurality of, and every daughter board 2 includes load board and collection board.

The board card connector is provided with a plurality of clamping grooves for connecting the sub boards, each clamping groove is provided with a unique address, and when the sub boards are connected with the clamping grooves, the sub boards acquire corresponding clamping groove addresses and add the corresponding clamping groove addresses to the interactive CAN information. Specifically, since each cabinet has a separate address, each EMC load box has a separate address, and the card slot within each EMC load box has a separate address. And when the daughter board is inserted into the corresponding card slot, automatically acquiring the card slot address and carrying the card slot address in the CAN information. Each sub-board is provided with a microprocessor system for data acquisition and operation.

The motherboard 1 is used for acquiring the CAN information of each daughter board, and uploading the CAN information to the upper computer after summarizing the CAN information. The motherboard 1 CAN integrate CAN information from each acquisition board and communicate with an upper computer through another CAN.

In addition, the interaction between the daughter board 2 and the motherboard 1 uses standard 4-bit address identification lines, power supply lines, CAN or other communication lines. The address identification line is represented by different combinations of high and low levels of 4 lines generated by the motherboard, for example 0000 represents a card slot 1,0001 represents a card slot 2, when the card slot is plugged into the daughter board, the single chip of the daughter board 2 can determine its own address from the high and low levels of the 4-bit address line, and the source and the sending position of the message are determined through the address in the software message configuration interface.

In the embodiment, the EMC load box of the system is further provided with a filtering module, and the filtering module includes: a power filter and a harness filter. The power filter is independently arranged in a separated space and is arranged at the inlet of the power line, so that the power filter is better integrated with the interface and is ensured to be connected with the chassis ground of the EMC load box, and the influence of the line beam hole on electromagnetic shielding is reduced. The filtering module mainly has the functions that:

1. the method realizes the filtering of all wires entering and exiting the EMC load box, and designs special filters aiming at different signals. The interference signals on the wire harness are effectively filtered through adjusting the parameters of the filter, so that the interference generated in the wire harness is separated from the wire harness interference;

2. the interference signals coupled to the external cable of the EMC load box are absorbed and transmitted by the filter and are not transmitted to the interior of the EMC load box, and the operation of the internal circuit of the EMC load box is not interfered.

In the concrete implementation mode, the shielding box body can be divided into an external large box body and a load box which is used for independently providing shielding for the board card, the box body is provided with a light-load fuma foot and a binding post which are convenient for the box body to move, and the binding post is connected with a copper net to be grounded, so that the current generated by an external electric field and a magnetic field can be effectively prevented.

It should be noted that the system can be provided with a plurality of EMC load boxes, and the EMC load boxes can be interconnected and controlled and monitored by the same upper computer. When the system is used, the ECU resource allocation can select the corresponding address board card, so that one EMC load box can support testing of a plurality of ECUs.

The EMC automatic test system of the vehicle-mounted electronic control unit comprises an EMC load box, a signal conversion module, a test wire harness and an upper computer, wherein the EMC load box comprises a motherboard, a board connector, a daughter board, a data interface connected with an ECU, a shielding box body and a filtering module. The motherboard is connected with the resource integration to the board connector, all functional boards and load boards are fixed on the guide rail of the inner box of the shielding box body, the ECUs of different platforms are matched by replacing and combining different sub boards, and meanwhile, the function expansion and maintenance replacement are convenient, and the maintenance cost is reduced. The control software in the upper computer realizes the control of the running working condition of the ECU, carries out scheduling, analysis and real-time display of the test result on the EMC test data of the ECU according to the corresponding working condition, collects, identifies, displays and records the measurement signals, has the functions of monitoring all test data in real time, receiving and sending CAN messages, setting working conditions, managing test projects, alarming out-of-tolerance and the like, flexibly configures PWM input and output of a load device through CAN information, flexibly configures switching value input, analog value input and frequency value input, configures the working state of a monitoring output actuator and realizes the automation of an EMC test system. In order to realize the EMC test meeting the ECUs of different platforms, the system provides necessary signal excitation and load state acquisition, can ensure that the ECUs run in expected working conditions in the EMC test process, realizes automatic control and monitoring, simplifies external connection, improves EMC test efficiency, and realizes the lowest-cost EMC test.

Referring to fig. 4, the invention also discloses an EMC automatic test method of the vehicle-mounted electronic control unit, which comprises the following steps:

s1: and determining the input and output states of the vehicle-mounted electronic control unit.

In a specific embodiment, data interaction is performed through CAN communication to determine the input and output states.

S2: when the vehicle-mounted electronic control unit is in an input state, the upper computer determines the output of an EMC load box hardware channel through a CAN protocol command; the vehicle-mounted electronic control unit generates a corresponding feedback signal after acquiring the output of the corresponding channel, and uploads the feedback signal to the upper computer through a CAN protocol; the upper computer determines a test result by comparing the feedback signal with a corresponding preset value.

In a specific embodiment, for the input of the ECU, the upper computer determines the output of the hardware channel of the EMC load box through a CAN protocol command, and after the ECU collects the output of the channel, the collected result is fed back to the upper computer through the CAN protocol, and the upper computer compares the set value with the collected value of the ECU to determine the test result.

S3: when the vehicle-mounted electronic control unit is in an output state, the upper computer sends output parameters to the vehicle-mounted electronic control unit through a CAN protocol; the vehicle-mounted electronic control unit outputs a hardware channel according to the control parameters; and comparing the hardware driving parameters acquired by the upper computer with the corresponding set values so as to determine a test result.

In a specific embodiment, for the output of the ECU, the upper computer sends the output parameters to the ECU through the CAN protocol, the ECU outputs the hardware channel according to the control parameters, and the acquisition card acquires the hardware driving parameters and compares the hardware driving parameters with the set values of the upper computer to determine the test result. As an example, the ECU may also collect itself (frequency input collects the cycle duty cycle of PWM, etc.), and the remaining channels are input through the collection card.

In conclusion, the invention is suitable for electromagnetic compatibility testing of vehicle-mounted electronic control units of different platforms, has universality, does not need to repeatedly customize EMC load devices for controller development of different projects, and reduces product development time and cost.

In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, so that the same or similar parts between the embodiments are referred to each other. For the method disclosed in the embodiment, since it corresponds to the system disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section.

Finally, it is further noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The EMC automatic test system and the method of the vehicle-mounted electronic control unit provided by the invention are described in detail. The principles and embodiments of the present invention have been described herein with reference to specific examples, the description of which is intended only to facilitate an understanding of the method of the present invention and its core ideas. It should be noted that it will be apparent to those skilled in the art that various modifications and adaptations of the invention can be made without departing from the principles of the invention and these modifications and adaptations are intended to be within the scope of the invention as defined in the following claims.

Claims

1. An EMC automatic test system of a vehicle-mounted electronic control unit, comprising: the system comprises a vehicle-mounted electronic control unit, an EMC load box, a signal conversion module and an upper computer; the vehicle-mounted electronic control unit is in data connection with the EMC load box through a test wire harness, the EMC load box is in data connection with the signal conversion module through an optical fiber, and the signal conversion module is in data connection with the upper computer;

the EMC load box is used for communicating with the upper computer through the CAN network and feeding back test data to the upper computer; the test wire harness is connected with the vehicle-mounted electronic control unit to provide signals for the vehicle-mounted electronic control unit and collect signals of test samples; the upper computer is internally provided with upper computer control software, and is used for transmitting an upper computer working condition test instruction to the EMC load box through the built-in optical fiber transceiver, outputting a required signal to the vehicle-mounted electronic control unit through a function board card in the EMC load box, and simultaneously transmitting an acquired signal to the upper computer to be compared with a test standard so as to generate a test result, and displaying the running state of the EMC load box in real time by the upper computer.

2. The EMC automatic test system of an on-vehicle electronic control unit according to claim 1, wherein the signal conversion module includes: a CAN optical fiber converter and a CAN-to-USB converter; the CAN optical fiber converter is respectively connected with the EMC load box and the CAN-to-USB converter in data, and the CAN-to-USB converter is connected with the upper computer in data; the CAN optical fiber converter is used for converting an input CAN signal into an optical signal, converting the optical signal into the CAN signal and outputting the CAN signal;

the CAN-to-USB converter is used for converting CAN signals into USB signals so as to realize the communication between the EMC load box and the upper computer; and sending a command corresponding to the working condition mode sent by the upper computer according to the defined actual working condition to the EMC load box so as to control the corresponding output state of the EMC load box, executing corresponding acquisition work and feeding the acquisition information back to the upper computer.

3. The EMC automatic test system of the vehicle-mounted electronic control unit according to claim 2, wherein a shielding box body is arranged in the EMC load box, a guide rail is arranged in the shielding box body, and a board card is arranged on the guide rail and comprises a motherboard, a daughter board, a board card connector, a power interface and a data interface; the power interface and the data interface are arranged on the motherboard, the motherboard is connected with the daughter board through the board card connector, and the motherboard is connected with the vehicle-mounted electronic control unit through the data interface;

the board card connector is provided with a plurality of clamping grooves for connecting the sub-boards, each clamping groove is provided with a unique address, and when the sub-boards are connected with the clamping grooves, the sub-boards acquire corresponding clamping groove addresses and add the corresponding clamping groove addresses to the interactive CAN information;

and the mother board is used for acquiring the CAN information of each daughter board, and uploading the CAN information to the upper computer after the CAN information is summarized.

4. The EMC automatic test system of the on-vehicle electronic control unit according to claim 3, wherein a filter module is further arranged in the EMC load box;

and the filtering module is used for carrying out filtering treatment on all the wires entering and exiting the EMC load box so as to filter interference signals coupled on the wires.

5. The EMC automatic test system of an on-vehicle electronic control unit according to claim 4, wherein the filtering module includes: a power filter and a harness filter;

the power filter is arranged in a preset independent space in the EMC load box, and the preset independent space is arranged at a power inlet of the EMC load box; the harness filter is positioned along the wires into and out of the EMC load box to absorb and transmit the interference signals coupled on the wires.

6. The EMC automatic test system of the on-vehicle electronic control unit according to claim 3, wherein an address identification line, a power supply line and a communication line are provided in the board connector;

the address identification lines are 4 and are used for representing a 4-bit card slot address according to signals of high and low level strokes, when the sub-card is connected with the card slot, a singlechip of the sub-card determines own address through the high and low levels of the 4 address identification lines, and a software message configuration interface determines the source and the sending position of a message through the address.

7. An EMC automatic test system for an on-board electronic control unit according to claim 3, further comprising a battery electrically connected to the power interface via a power cord.

8. The automatic EMC testing system of the on-vehicle electronic control unit according to claim 1, wherein the EMC load box is provided with a clamp Ma Jiaolun and a binding post;

the Fuma foot wheels are arranged at the bottom of the EMC load box and used for moving the box body;

the binding post is grounded through a connecting copper net.

9. An EMC automatic test method of an on-board electronic control unit, characterized in that the method employs an EMC automatic test system of an on-board electronic control unit as claimed in any one of claims 1 to 8, the method comprising: determining the input and output states of the vehicle-mounted electronic control unit;

10. The method for EMC automatic testing of an on-board electronic control unit according to claim 9, further comprising: