Internet of Things charging pile automatic equipment test system

Abstract

The invention relates to an Internet of Things charging pile automatic equipment test system, which comprises an upper computer and a jig, the jig comprises an ST-Link debugger and a grounding end, the grounding end is connected with a first path of GPIO port and a second path of GPIO port and is used for realizing signal pull-down to enter an equipment test mode, and the upper computer is connected with an SWD debugging port through the ST-Link debugger and is used for realizing signal pull-down to enter an equipment test mode. The upper computer is used for running a downloading program, writing firmware into the MCU and completing firmware loading, the firmware is used for controlling communication between the circuit output serial port and the upper computer and between the equipment input and output serial port and the upper computer so as to carry out testing, and the circuit output serial port and the equipment input and output serial port are both connected with the upper computer so as to carry out testing on the circuit output serial port and the equipment input and output serial port. And the equipment input and output serial port is used for transmitting a test instruction of the upper computer to the MCU and returning a test result to the upper computer. Compared with the prior art, the method has the advantages of automatic testing and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of charging pile equipment testing, and in particular to an Internet of Things charging pile automation equipment testing system. Background Art

[0002] In recent years, electric vehicles and electric bicycles have developed rapidly and become important means of transportation for the general public. With the development of network and electronic technology, AC charging piles based on Internet of Things technology have become a common tool for charging electric vehicles. After the core circuit board of this type of charging pile completes the device mounting in the generation stage, it is necessary to load the controller (Microcontroller Unit, MCU) firmware, write the charging pile configuration information, and conduct comprehensive tests on the onboard functional modules to ensure that the circuit board meets the factory quality requirements.

[0003] The existing technical solutions include the article "Design of an AC Charging Pile Detection Device" published in Volkswagen Technology in December 2023 (Volume 25, Issue 292), which introduces the design principle, hardware design, software design and circuit measurement method of the AC charging pile automatic detection device, and designs a highly integrated AC charging pile test device. The charging pile is tested through the designed charging pile test device. This device requires an independent test device.

[0004] Other methods include the article "Technical Principles and Equipment Detection of Automobile Charging Pile-AC" published in the 4th issue of New Horizon in 2024, which introduces the technical principles of automobile AC charging piles and the detection methods of charging piles. The method introduced in the article tests the charging pile by using test equipment to detect the voltage and other indicators of different detection points at different stages of the insertion and removal of the charging gun plug. This detection method requires external test equipment and requires manual connection of each detection point. Therefore, there is room for improvement and development in the existing technology. Summary of the invention

[0005] The purpose of the present invention is to provide an Internet of Things charging pile automation equipment testing system that realizes independent automated testing.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] An Internet of Things charging pile automation equipment testing system is used to test a charging pile core circuit board, characterized in that an MCU and a tested component connected thereto are provided on the charging pile core circuit board, the MCU comprises a plurality of ports, including a SWD debugging port, a circuit output serial port, an equipment input and output serial port, a first GPIO port and a second GPIO port, respectively, the testing system comprises a host computer and a fixture, the fixture comprises an ST-Link debugger and a grounding terminal, the grounding terminal is connected to the first GPIO port and the second GPIO port, and is used to realize signal pull-down to enter the equipment test mode, the host computer is connected to the SWD debugging port through the ST-Link debugger, and is used for the host computer to run a download program, write the firmware into the MCU, and complete the firmware loading, the firmware is used to control the communication between the circuit output serial port and the equipment input and output serial port and the host computer for testing, the circuit output serial port and the equipment input and output serial port are both connected to the host computer, the circuit output serial port is used to output the debugging information of the MCU to the host computer, and the equipment input and output serial port is used to pass the test instructions of the host computer to the MCU, and return the test results to the host computer.

[0008] Furthermore, the component under test includes an onboard voltage module, a communication module, a voltage sensor, a current sensor, a relay, a temperature sensor and a buzzer. The host computer sends a test instruction to the MCU through the equipment input and output serial port. The MCU tests the corresponding component under test according to the test instruction to complete the test process of the corresponding component under test.

[0009] Furthermore, the onboard voltage output end of the onboard voltage module is provided with a plurality of voltage dividing points to divide the onboard voltage, and the voltage dividing points are connected to the first GPIO port or the second GPIO port. The first GPIO port or the second GPIO port converts the analog signal of the onboard voltage into a digital signal, inputs it into the MCU, and completes the test process of the onboard voltage module according to the onboard voltage test instruction issued by the host computer.

[0010] Furthermore, the communication module is provided with a TTL level serial port, and the TTL level serial port is connected to the first GPIO port or the second GPIO port to realize the connection between the communication module and the MCU, the TTL level serial port is used for bidirectional data transmission, the first GPIO port or the second GPIO port is used to send control information to the communication module, and the test process of the communication module includes:

[0011] Send a control signal through the first GPIO port or the second GPIO port to initialize the communication module;

[0012] The MCU receives the communication test instruction from the host computer, starts to drive the communication module, initiates a TCP three-way handshake to the IoT platform, performs identity authentication, and feeds back the verification result to the host computer. If the identity authentication with the IoT platform is completed, it indicates that the communication module is working properly, otherwise it indicates that the communication module is not working properly.

[0013] Furthermore, the voltage sensor is connected to the MCU via an SPI interface, and the current voltage value of the voltage sensor is read via the SPI interface to implement a test process of the voltage sensor.

[0014] Furthermore, the current sensor is provided in plurality, each current sensor is connected to the MCU via an SPI interface, and the testing process of the current sensor and the relay includes:

[0015] MCU receives current test instructions from the host computer;

[0016] Disconnect the relay, read the current value of each current sensor in turn through the SPI interface, compare it with the corresponding reasonable current value, and feedback the test results to the upper computer;

[0017] Connect the relays, read the current value of each current sensor in turn through the SPI interface, compare it with the corresponding reasonable current value, and feed back the test results to the host computer.

[0018] Further, the temperature sensor is connected to the MCU via the first GPIO port or the second GPIO port, and the test process of the temperature sensor includes:

[0019] The MCU receives the temperature test instruction sent by the host computer, reads the current temperature value of the temperature sensor, and compares it with the reasonable temperature value to complete the test process of the temperature sensor.

[0020] Furthermore, the buzzer is connected to the MCU via the first GPIO port or the second GPIO port, and the MCU completes the buzzer test process by receiving a buzzer test instruction from a host computer.

[0021] Furthermore, the host computer is connected to the ST-Link debugger via a USB cable.

[0022] Furthermore, the ST-Link debugger is connected to the SWD debug port via four wires: VCC, GND, SWIO, and CLK.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) In the existing methods, the core circuit board test of the electric vehicle charging pile usually requires the use of dedicated external equipment to evaluate various functions. However, the present invention writes the firmware into the MCU through the host computer, providing a basis for the core circuit board test, and realizing the concentration of the test function inside the charging pile. Through the cooperation of MCU control and GPIO port signal pull-down, various tests are automatically completed in the test mode, avoiding the involvement of external devices.

[0025] (2) The present invention automatically collects data through the MCU and the various interfaces connected to it. The MCU automatically detects the working conditions of various functional modules such as the onboard voltage, communication module, and sensor according to the set instructions. In the test process of the present invention, it is no longer necessary to manually connect the various detection points on the circuit board, thereby avoiding the errors or omissions caused by manually connecting the detection points in the traditional method, greatly simplifying the test process and improving the accuracy and consistency of the test.

[0026] (3) The present invention highly integrates the test function into the core circuit board of the charging pile, without the need to add external modules or equipment. This design allows the charging pile to complete comprehensive functional testing by itself during the production stage, and ensures that each module can pass strict quality inspection before normal operation. Since the test function is integrated into the circuit board, it reduces additional hardware requirements and reduces the device compatibility issues that may arise during the test process, thereby improving the convenience and efficiency of the test and further optimizing the structure and cost of the charging pile. In addition, this integrated design also provides convenience for later maintenance, and the test function can be enabled at any time when necessary, which improves the overall stability of the equipment.

[0027] (4) The present invention automatically determines whether the charging pile enters the test mode through the status of the two GPIO port pins of the MCU, and completes the test of each functional module of the circuit board in this mode. The entire test process does not require manual intervention. The MCU checks the working status of functional modules such as voltage, communication, and sensor in turn according to the predetermined test program, and automatically feeds back the test results. This fully automated testing method not only shortens the test time, but also greatly reduces the error rate of manual operation, ensuring that the product can meet the predetermined quality standards before leaving the factory. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall system of the present invention;

[0029] Figure 2 This is the upper computer software operation interface diagram of the present invention

[0030] Figure 3 This is a 5V voltage AD conversion circuit of the circuit board of the present invention. DETAILED DESCRIPTION

[0031] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0032] The present embodiment provides an Internet of Things charging pile automation equipment testing system, which is used to test the charging pile core circuit board. The charging pile core circuit board 1 is provided with an MCU 1-1 and a component to be tested connected thereto. The component to be tested includes an onboard voltage module 1-2, a communication module 1-3, a voltage sensor 1-4, a current sensor 1-5, a relay 1-6, a temperature sensor 1-7 and a buzzer 1-8. The MCU 1-1 includes multiple ports, including a SWD debugging port 1-1-1, a circuit output serial port 1-1-2, an equipment input and output serial port 1-1-3, a first GPIO (General Purpose Input and Output) port 1-1-4 and a second GPIO port 1-1-5. Each port is led out to the edge of the charging pile core circuit board. In the equipment testing stage, these ports are connected to different ports of the host computer 3 through a fixture 2. The specific port connection method is as follows: Figure 1 .Depend on Figure 1 It can be seen that the host computer 3 is connected to the ST-Link debugger 2-1 in the fixture 2 through a USB cable, and the ST-Link debugger 2-1 is then connected to the SWD debug port 1-1-1 of the single chip on the circuit board through four lines, which are VCC (Voltage Common Collector, positive power supply voltage), GND (Ground), SWIO (SmartWireless I / O), and CLK (Clock) lines; the two serial port lines of the host computer 3 pass through the fixture 2 (without processing) and are connected to the two serial ports of the circuit board, among which the circuit output serial port (serial port 1) outputs the debugging information of the MCU1-1 on the circuit board to the host computer 3, and the equipment input and output serial port (serial port 2) transmits the test instructions of the host computer 3 to the MCU 1-1 of the circuit board, and outputs the test results of the MCU 1-1 on the circuit board to the host computer 3; the two GPIO ports on the circuit board are connected to the ground terminal 2-2 on the fixture 2 to achieve signal pull-down.

[0033] The host computer 3 is connected to the ST-Link debugger 2-1 in the fixture 2 through the USB port, and the ST-Link debugger 2-1 is connected to the MCU 1-1 of the circuit board through the SWD debug port 1-1-1. The host computer 3 runs the download program, writes the firmware to the MCU 1-1 through the above link, and completes the firmware loading. The subsequent charging pile test and formal operation are based on this firmware. After the firmware is loaded, run the firmware in test mode. Under the control of this firmware, the entire charging pile communicates with the host computer 3 through the serial port to complete the entire test process.

[0034] The 2 GPIO ports of MCU 1-1 on the circuit board are pulled high by default. When connected to fixture 2, the 2 ports are pulled low. After resetting the circuit board, MCU 1-1 on the board reads the status of the 2 GPIO ports. When the 2 ports are low at the same time, MCU 1-1 will run in equipment test mode. The purpose of setting 2 GPIO ports is to prevent MCU 1-1 from entering equipment mode due to a single port being pulled low by mistake during the actual operation of the circuit board, which affects the normal operation of the charging pile.

[0035] After the circuit board enters the equipment test mode, the host computer software sends a test instruction to MCU 1-1 through serial port 2. MCU1-1 executes the specific test code according to the received instruction and feeds back the test result to the host computer 3 through serial port 2. The running interface of the host computer software is shown in Figure 2 .

[0036] (1) Onboard voltage module 1-2 test

[0037] The upper computer 3 sends a voltage test instruction, and the charging pile performs a voltage test operation after receiving the instruction through the serial port. The GPIO port of the onboard MCU 1-1 has an AD conversion (analog-to-digital conversion) function, which can convert the collected analog signal into a digital signal and input it into MCU 1-1. The AD sampling accuracy of the MCU 1-1 is 12 bits, that is, when the voltage of the AD input port is 3.3V, the digital quantity read by MCU 1-1 is 212-1=4095; when the voltage of the AD input port is 0V, the digital quantity read by MCU 1-1 is 0; the collected values ​​input at other voltages vary linearly between 0 and 4095. The reference voltage of the AD conversion module can be specified in the design stage. When drawing the circuit diagram, connect the AD reference voltage pin of MCU 1-1 to a 3.3V voltage source. Taking the 5V voltage detection on the circuit board as an example, the schematic diagram of the voltage detection circuit is shown in Figure 3 .

[0038] Depend on Figure 3It can be seen that the onboard 5V voltage (VD) is divided by voltages of 1K and 220ohm respectively, and the voltage dividing point is connected to the AD input port PC4 of MCU 1-1. If the onboard 5V voltage has no deviation, the voltage at the voltage dividing point is about 5*220 / (220+1000)≈0.9V, and the obtained digital input quantity is about 4095*0.9 / 3.3≈1117. In the actual operation process, the voltage will have a certain amplitude up and down, and here we take plus or minus 5% as a reasonable interval, that is, if the collected digital quantity is within the range of (1117*0.95,1117*1.05), then it can be determined that the current onboard 5V voltage is in the correct range, otherwise it is necessary to check whether there is a problem in the circuit board during the production process. After completing the voltage test, MCU 1-1 feeds back the result of whether the voltage test is passed to the upper computer 3. The test method of each voltage on other boards is the same as the test method of 5V voltage, and will not be repeated here.

[0039] (2) Communication module 1-3 test

[0040] MCU 1-1 and communication module 1-3 are connected through a TTL (Transistor-Transistor Logic) level serial port and several GPIO ports. The serial port is used for bidirectional data transmission, and the GPIO port is used to send control information such as module initialization. After receiving the communication test instruction from the host computer 3, MCU 1-1 drives the communication module 1-3, initiates a TCP three-way handshake to the IoT platform, and completes the identity authentication. If the single chip successfully completes the identity authentication with the IoT platform, it means that the communication module 1-3 of the entire circuit is working properly. MCU 1-1 feedbacks the communication test success result to the host computer 3, otherwise feedbacks the communication test failure result.

[0041] (3) Input voltage sensor 1-4 test

[0042] The MCU 1-1 and the input voltage sensor 1-4 are connected via an SPI (Serial Peripheral Interface) interface. After receiving the input voltage test instruction from the host computer 3, the MCU 1-1 reads the current voltage value of the voltage sensor 1-4 through the SPI port and feeds back the test result to the host computer 3.

[0043] (4) Current sensor 1-5 and relay 1-6 test

[0044] MCU 1-1 and each current sensor 1-5 on the board are connected via an SPI interface, and different current sensors 1-5 are selected by pulling down different GPIO ports. After receiving the current test instruction from the host computer 3, MCU 1-1 first disconnects relay 1-6, reads the current of each current sensor 1-5 in turn, compares the read current value of each port with a reasonable value, and feeds back the test result to the host computer 3; then closes relay 1-6, reads the current of each current transformer in turn, compares the read current value of each port with a reasonable value, and feeds back the test result to the host computer 3.

[0045] (5) Temperature sensor 1-7 test

[0046] MCU 1-1 is connected to temperature sensor 1-7 through a GPIO port, and realizes temperature data reading according to the single bus communication standard of temperature sensor 1-7. After receiving the temperature test instruction from host computer 3, MCU 1-1 reads the current value of temperature sensor 1-7, compares it with the reasonable temperature of the current test environment, and feeds back the test result to host computer 3.

[0047] (6)Buzzer 1-8 test

[0048] MCU 1-1 is connected to buzzer 1-8 via a GPIO port, and buzzer 1-8 is activated by pulling down the GPIO port. After MCU 1-1 receives the buzzer test instruction from host computer 3, the tester judges whether the buzzer is working properly by listening to the sound of buzzer 1-8.

[0049] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0050] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. An IoT charging pile automation equipment testing system, used to test the core circuit board of the charging pile, characterized in that: The charging pile core circuit board (1) is provided with an MCU (1-1) and a component under test connected thereto, the MCU (1-1) comprising a plurality of ports, respectively comprising an SWD debugging port (1-1-1), a circuit output serial port (1-1-2), an equipment input and output serial port (1-1-3), a first GPIO port (1-1-4) and a second GPIO port (1-1-5), the test system comprising a host computer (3) and a fixture (2), the fixture (2) comprising an ST-Link debugger (2-1) and a ground terminal (2-2), the ground terminal (2-2) being connected to the first GPIO port (1-1-4) and the second GPIO port (1-1-5) for realizing a signal pull-down to enter an equipment test mode, the host computer (3) being connected to the first GPIO port (1-1-4) and the second GPIO port (1-1-5) through an ST-Link debugger (2-1). The nk debugger (2-1) is connected to the SWD debug port (1-1-1) and is used for the host computer (3) to run a download program, write firmware into the MCU (1-1), and complete firmware loading. The firmware is used to control the communication between the circuit output serial port (1-1-2) and the equipment input and output serial port (1-1-3) and the host computer (3) for testing. The circuit output serial port (1-1-2) and the equipment input and output serial port (1-1-3) are both connected to the host computer (3). The circuit output serial port (1-1-2) is used to output the debugging information of the MCU (1-1) to the host computer (3). The equipment input and output serial port (1-1-3) is used to transfer the test instructions of the host computer (3) to the MCU (1-1) and return the test results to the host computer (3).

2. The IoT charging pile automation equipment testing system according to claim 1, characterized in that: The tested component comprises an onboard voltage module (1-2), a communication module (1-3), a voltage sensor (1-4), a current sensor (1-5), a relay (1-6), a temperature sensor (1-7) and a buzzer (1-8); a host computer (3) sends a test instruction to an MCU (1-1) via an equipment input and output serial port (1-1-3); and the MCU (1-1) tests the corresponding tested component according to the test instruction, thereby completing the test process of the corresponding tested component.

3. The IoT charging pile automation equipment testing system according to claim 2 is characterized in that: The onboard voltage output end of the onboard voltage module (1-2) is provided with a plurality of voltage dividing points for dividing the onboard voltage, and the voltage dividing points are connected to a first GPIO port (1-1-4) or a second GPIO port (1-1-5); the first GPIO port (1-1-4) or the second GPIO port (1-1-5) converts an analog signal of the onboard voltage into a digital signal, inputs the digital signal into the MCU (1-1), and completes a test process of the onboard voltage module (1-2) according to an onboard voltage test instruction issued by a host computer (3).

4. The IoT charging pile automation equipment testing system according to claim 2 is characterized in that: The communication module (1-3) is provided with a TTL level serial port, the TTL level serial port is connected to the first GPIO port (1-1-4) or the second GPIO port (1-1-5) to realize the connection between the communication module (1-3) and the MCU (1-1), the TTL level serial port is used for bidirectional data transmission, the first GPIO port (1-1-4) or the second GPIO port (1-1-5) is used to send control information to the communication module (1-3), and the test process of the communication module (1-3) includes: Sending a control signal through the first GPIO port (1-1-4) or the second GPIO port (1-1-5) to initialize the communication module (1-3); The MCU (1-1) receives a communication test instruction from a host computer, starts to drive a communication module (1-3), initiates a TCP three-way handshake to an Internet of Things platform, performs identity authentication, and feeds back the authentication result to the host computer (3). If the identity authentication with the Internet of Things platform is completed, it indicates that the communication module (1-3) is working properly; otherwise, it indicates that the communication module (1-3) is not working properly.

5. The IoT charging pile automation equipment testing system according to claim 2 is characterized in that: The voltage sensor (1-4) is connected to the MCU (1-1) via an SPI interface, and the current voltage value of the voltage sensor (1-4) is read via the SPI interface to implement a test process of the voltage sensor (1-4).

6. The IoT charging pile automation equipment testing system according to claim 2, characterized in that: A plurality of current sensors (1-5) are provided, each current sensor (1-5) is connected to the MCU (1-1) via an SPI interface, and a test process of the current sensor (1-5) and the relay (1-6) comprises: MCU (1-1) receives the current test instruction from the host computer (3); Disconnect the relay (1-6), read the current value of each current sensor (1-5) in turn through the SPI interface, compare it with the corresponding reasonable current value, and feed back the test result to the upper computer (3); The relay (1-6) is connected, and the current value of each current sensor (1-5) is read in turn through the SPI interface, and compared with the corresponding reasonable current value, and the test result is fed back to the upper computer (3).

7. The IoT charging pile automation equipment testing system according to claim 2, characterized in that: The temperature sensor (1-7) is connected to the MCU (1-1) via the first GPIO port (1-1-4) or the second GPIO port (1-1-5), and the test process of the temperature sensor (1-7) includes: The MCU (1-1) receives a temperature test instruction sent by a host computer, reads a current temperature value of the temperature sensor (1-7), and compares it with a reasonable temperature value, thereby completing a test process of the temperature sensor (1-7).

8. The IoT charging pile automation equipment testing system according to claim 2, characterized in that: The buzzer (1-8) is connected to the MCU (1-1) via a first GPIO port (1-1-4) or a second GPIO port (1-1-5), and the MCU (1-1) completes a test process of the buzzer (1-8) by receiving a buzzer test instruction from a host computer (1).

9. The IoT charging pile automation equipment testing system according to claim 1, characterized in that: The host computer (3) is connected to the ST-Link debugger (2-1) via a USB cable.

10. The IoT charging pile automation equipment testing system according to claim 1, characterized in that: The ST-Link debugger (2-1) is connected to the SWD debug port (1-1-1) via four wires: VCC, GND, SWIO, and CLK.

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