Centralized automobile alternating current charging pile and charging control method

Abstract

The invention is suitable for the technical improvement field of new energy automobile charging equipment, and provides a centralized automobile alternating current charging pile and a charging control method, according to the charging pile, a mainboard is arranged in a waterproof and fireproof box body, alternating current is introduced through a wire inlet, and the wire inlet diameter is determined according to the number of gun wires. The control mainboard integrates multiple functions, is provided with a control guide device, a power supply on-off device, a temperature detection device and an electric quantity metering device for each gun, and is further provided with a networking and leakage protection device. The charging pile can be connected with a plurality of gun lines, each gun line is provided with a two-dimensional code gun base, and a user scans a code and starts charging after authentication of a background server. Compared with a traditional charging pile, one device can charge multiple automobiles at the same time, the installation process is optimized, material and manpower consumption is reduced, leakage protection and networking devices are saved, network overhead is reduced, and the charging pile has remarkable advantages in the field of new energy automobile charging and is wide in application prospect.

Description

Technical Field

[0001] The present invention belongs to the field of improvement of charging technologies, and particularly relates to a centralized automotive AC charging pile and a charging control method. Background Art

[0002] With the country's strong promotion of new energy vehicle production, automotive supporting charging piles are becoming increasingly urgent. An automotive AC charging pile is a device that provides AC input, CP (control pilot) signal, safety protection (such as leakage and overheating), metering and billing, and remote start for the OBC (On-board charger) of a vehicle. AC charging piles are widely used due to their advantages such as low cost, low power supply capacity requirements, and convenient use. The current single-form and single-pile installation method is still complicated and consumes a large amount of manpower. Summary of the Invention

[0003] The purpose of the present invention is to provide a centralized automotive AC charging pile and a charging control method, aiming to solve the technical problem that existing charging piles can only charge one vehicle at a time.

[0004] The present invention is implemented as follows. A centralized automotive AC charging pile, the centralized automotive AC charging pile includes A charging pile box body, which has an accommodation space inside for centrally arranging the charging system of the charging pile; An inlet port, which is an inlet port provided on the charging pile box body for introducing single-phase or three-phase electricity into the charging pile box body through an inlet cable and connecting it to an air switch. The wire diameter of the inlet cable is determined according to the specific installation quantity of the charging line guns to be equipped for the actual charging pile to meet different power requirements; A control main board, which is arranged inside the charging pile box body for regulating the entire charging system. Through a main control chip, it controls the charging guidance, charging protection, charging start and stop of one-way AC input and multi-way charging line gun AC output of the charging pile, and a set of leakage protection, networking device, and gun line temperature detection are arranged on the control main board to cooperate with the main control chip to monitor and network the multi-way charging line guns, realizing the control of a set of charging system in the charging pile to control multi-way output charging line guns; A charging line gun assembly: multiple charging line guns are led out from the independent control main board of the charging pile, and each charging line gun independently provides AC charging services for a vehicle; A charging gun seat, with a charging gun seat corresponding to the end of each charging line gun. A dedicated QR code is silk-screened on the surface of the charging gun seat, and users can start the charging service of the corresponding charging line gun by scanning the QR code.

[0005] A further technical solution of the present invention is that the following modules are integrally arranged on the control main board, including: Charging guidance control module: An independent control and guidance signal generation and detection device is equipped for each charging gun, which is used to generate and receive charging guidance signals to realize the charging interaction between the charging pile and the vehicle; Power supply control module: Two (for single-phase power) or three (for three-phase power) relays are configured for each charging gun to control the on / off of the power supply between the charging gun and the power source; Temperature monitoring module: A gun line temperature detection device is set corresponding to each charging gun to monitor the gun line temperature in real time to ensure charging safety; Electricity metering module: An electricity metering device is equipped for each charging gun to accurately measure the charging electricity of each gun and perform billing processing; Communication module: It includes a set of networking devices, which are used to interact with the background server to realize remote monitoring and management; Leakage protection module: It includes a set of leakage protection devices to monitor and protect the leakage situation of the entire charging pile.

[0006] A further technical solution of the present invention is that the centralized AC charging pile for vehicles further includes: Power supply control component, which is used to control the on / off of the power supply of the entire charging pile and has overload and short-circuit protection functions; Grounding component: A grounding bar is provided, which is connected to the charging gun, the control main board and the protection box to ensure electrical safety; Electrical connection component: It includes an output wiring point and a gun temperature wiring point. The output wiring point is used to connect the charging gun and the control main board to realize power transmission; the gun temperature wiring point is used to connect the gun line temperature detection device and the charging gun to transmit temperature signals; CP signal connection component: A CP wiring point is set to connect the control and guidance signal generation and detection device and the charging gun to realize the transmission and interaction of CP signals.

[0007] A further technical solution of the present invention is that the charging guidance control module is composed of a main control chip. The main control chip is used to generate and monitor CP signals, monitor protection devices, communicate with the background server through networking devices, and control the on / off of the relay according to CP signals, protection signals and background data; the main control chip has the following functions: Signal processing function: Generate and monitor CP signals in real time, and judge the charging status according to signal changes; Protection monitoring function: Real-time monitor protection signals such as leakage and over-temperature to ensure the safety of the charging process; Communication control function: Communicate with the background server through the communication module, receive server instructions and upload the charging pile status data, and control the on / off of the relay according to CP signals, protection signals and server data; Billing management function: During the charging process of the vehicle, it monitors the data of the electricity metering device in real time and performs accurate metering and billing processing.

[0008] A further technical solution of the present invention is that: the control main board further includes: AC to DC circuit, which is used to convert 220V alternating current into 12V direct current to provide a stable DC power supply for the control main board and other functional modules; -12V generation circuit, which is used to generate -12V voltage to provide the required power supply for the processing and transmission of CP signals; DC buck circuit, which is used to step down 12V direct current to 4.2V, and 4.2V supplies power to the main control chip and related circuit modules with low voltage requirements; Grounding detection circuit, which is used to detect the grounding status of the charging pile in real time and send out a protection signal in time when the grounding is abnormal; Relay control circuit, which is used to control the opening and closing of the relay according to the instructions of the main control chip to realize the on-off control between 220V alternating current and the vehicle; Electricity metering and protection circuit, where each charging gun corresponds to an electricity metering and protection circuit unit, which realizes the functions of charging electricity metering and current calculation, and has overvoltage, undervoltage, overcurrent, and leakage protection functions; CP signal processing circuit, which includes a CP signal generation circuit and a CP feedback circuit. The CP signal generation circuit converts the PWM signal sent by the main control chip into a CP signal that meets the standard, and one path is configured for each gun; CP feedback circuit, which is used to feedback the real-time change of the CP signal fed back by the vehicle end to the main control chip, and one path is also configured for each gun.

[0009] Another object of the present invention is to provide a charging control method for a centralized vehicle AC charging pile. The charging control method for the centralized vehicle AC charging pile includes the following steps: System initialization step: After the 220V power supply enters the main board, the AC to DC circuit obtains low-voltage direct current for each functional module to work; after the main control is powered on, it boots up automatically, initializes the system parameters, starts the protection detection program, monitors the voltage and current data in real time, establishes a network connection with the background server at the same time, generates a CP signal, and starts monitoring the CP signal status; Charging preparation detection step: After the user inserts the gun, the corresponding CP signal changes. The main control monitors the CP status through the CP feedback circuit and judges whether it meets the charging requirements according to the preset charging conditions. If it does not meet, it immediately notifies the user to exit the charging through methods such as light flashing and voice prompts; if it meets, it enters the waiting for charging instruction state; Charging authorization and startup steps: The charging pile receives the start charging instruction sent by the background server based on the user's code scanning information through the networking device. After receiving the instruction, the main control, according to the instruction information, controls the corresponding relay to close, enabling the 220V alternating current to be transmitted to the vehicle OBC through the relay, gun line, and gun head in sequence, officially starting the charging process. At the same time, the corresponding power metering device is started to begin recording the charging power. Charging process monitoring steps: During the charging process, the main control continuously and real-time monitors the gun line temperature, voltage, current data, and the status of the CP signal. The gun line temperature is obtained through the gun line temperature detection device. If the temperature exceeds the safety threshold, cooling measures are immediately started or charging is stopped. The power metering device accurately measures the charging power and transmits the data to the main control in real-time. The CP signal is continuously monitored through the CP feedback circuit. If the CP signal is abnormal, charging is immediately stopped. Charging end control steps: When the charging pile receives the stop charging instruction sent by the server, or when the main control monitors that the CP signal does not meet the charging requirements, or protection alarms such as overvoltage, undervoltage, overcurrent, and leakage occur, the main control quickly controls the relay of the corresponding gun line to disconnect, cutting off the alternating current supply, ending the charging process of this gun, and uploading the final charging power data to the background server for billing and settlement.

[0010] A further technical solution of the present invention is that the system initialization step includes the following steps: Power supply startup steps: The 220V mains power is connected through the inlet and enters the control main board through the air switch. The AC to DC circuit converts the 220V alternating current into 12V direct current to supply power to each module. The -12V generation circuit outputs -12V voltage for the CP signal. The DC buck circuit steps down the 12V direct current to 4.2V to supply power to the main control. Device self-check steps: After the main control chip is powered on, it initializes internal registers, sets parameters such as interrupt vectors, etc. The grounding detection circuit is started to check the grounding status of the charging pile. If the grounding is abnormal, fault information is sent to the background server through the networking device, and at the same time, a fault prompt is displayed locally on the charging pile to prevent subsequent charging operations. Network connection and CP signal preparation steps: The networking device initializes the network connection and attempts to establish a TCP / IP connection with the background server. If the connection fails, it reconnects at the set time interval. The control signal generating device is controlled to generate an initial CP signal. The parameters such as the amplitude and frequency of the CP signal meet the national standard requirements, and the main control chip starts to monitor the status of the CP signal in real-time.

[0011] A further technical solution of the present invention is that the charging preparation detection step includes the following steps: Charging gun connection detection steps: The user inserts the charging gun into the vehicle charging interface, and the connection action changes the state of the CP signal line; the control and guidance signal detection device captures the change in the CP signal and feeds it back to the main control chip through the CP feedback circuit; Charging condition judgment steps: The main control chip analyzes the fed-back CP signal according to the preset charging conditions (such as the CP signal amplitude within the specified range, normal vehicle communication handshake, etc.). If the CP signal parameters are abnormal, the main control chip controls the indicator light of the charging pile to flash and the buzzer to sound, prompting the user that the charging gun connection is abnormal or the vehicle does not match, and the user needs to re-plug or replace the charging gun; if the CP signal meets the requirements, it enters the waiting state for a charging instruction.

[0012] A further technical solution of the present invention is that the charging authorization and start-up steps include the following steps: Scanning code information uploading steps: The user scans the QR code on the gun holder, and the mini-program or APP obtains the pile number and user identity information, and sends this information to the background server through the network; Permission and status verification steps: After receiving the request, the background server queries the database to verify the user's permissions (such as whether the account balance is sufficient, whether there is an arrears record, whether there are charging restrictions, etc.), and at the same time checks the status of the charging pile (whether it is idle, whether there is a fault, etc.). If the user's permissions are insufficient or the charging pile status is abnormal, the server returns an error message to the mini-program or APP, informing the user that charging cannot be performed; if the verification passes, the server sends a start charging instruction containing information such as the user ID, charging amount limit, and power limit to the charging pile; Charging start steps: After receiving the instruction, the networked device of the charging pile parses the instruction data and transfers it to the main control chip. The main control chip controls the relay control circuit according to the instruction, closes the relay corresponding to the charging gun, and makes the 220V alternating current pass through the relay, the gun line, and the gun head in sequence to access the vehicle OBC; at the same time, the main control chip sends a start instruction to the power metering device to start recording the charging power; The charging process monitoring steps include the following steps: Temperature monitoring steps: The gun line temperature detection device collects the gun line temperature data every certain period (such as 10 seconds) and transmits the data to the main control chip through communication protocols such as SPI or I2C; the main control chip compares the real-time temperature with the preset safety threshold (such as 75°C). If the temperature exceeds the threshold, the main control chip first controls the relay control circuit to cut off the power supply of the gun line and stop charging; then starts the cooling fan, and at the same time sends a temperature anomaly alarm message to the background server through the networked device, and displays a high temperature prompt locally on the charging pile to remind the user to pay attention to safety; Steps for monitoring power and current: In the power metering and protection circuit, the metering unit accumulates the charging power in real time based on the power metering chip, and the current detection unit monitors the charging current through a sampling resistor or a current transformer. The main control chip periodically reads the power and current data. If the current exceeds the preset overcurrent threshold (such as 16A, set according to the rated current of the charging pile), the main control chip immediately controls the relay to disconnect, stops charging, and notifies the user of the overcurrent fault through the indicator light and voice prompt. At the same time, the overcurrent data is uploaded to the background server for subsequent analysis. Steps for monitoring the CP signal: During the charging process, the main control chip continuously monitors the CP signal through the CP feedback circuit. If the CP signal shows abnormal fluctuations (such as amplitude mutation, abnormal frequency), the main control chip determines that the vehicle charging status is abnormal, immediately controls the relay to cut off the charging circuit, stops charging, and reports the abnormal situation of the CP signal to the background server through the networking device, prompting the user to check the vehicle charging interface or contact the customer service. Steps for monitoring leakage: The leakage protection device continuously monitors the residual current in the charging pile circuit, using detection means such as zero-sequence current transformers. Once the detected leakage current exceeds the set threshold (for example, 30mA), the leakage protection device quickly acts, cuts off all relays, stops the power supply of the entire charging pile, and at the same time triggers a local sound and light alarm to notify the user of the leakage danger. And it sends the leakage fault information to the background server through the networking device for timely repair.

[0013] The charging end control steps include the following steps: End condition judgment step: When any of the following conditions is met, it is determined that the charging is over: The charging pile receives a stop charging instruction issued by the background server (such as the user actively ends the charging on the APP, reaches the preset charging amount or power); the main control chip monitors that the CP signal does not meet the charging requirements; protection alarms such as overvoltage, undervoltage, overcurrent, and leakage occur. Charging stop operation step: After the main control chip receives the charging end signal, it controls the relay control circuit to disconnect the relay corresponding to the gun line, cutting off the 220V AC power supply. At the same time, the main control chip sends a stop metering instruction to the power metering device to obtain the final charging power data. Data upload and prompt step: The main control chip uploads information such as the final charging power data, charging duration, and charging fee (if settled) to the background server through the networking device for billing settlement and data statistics. The indicator light of the charging pile returns to the initial state, and there may be a voice prompt "Charging completed", notifying the user that the charging is finished, and the user can unplug the gun and leave.

[0014] A further technical solution of the present invention is that the step of uploading the scanned code information further includes The server checks the status of the charging pile and the user's permissions. If the check passes, the charging is started. The corresponding relay in the pile is turned on, and the OBC starts to charge the battery.

[0015] The beneficial effects of the present invention are as follows: The charging pile 1 can charge multiple cars simultaneously with one machine; the installation method is optimized, only one air switch, one set of shell materials, one base or column are needed during installation, saving materials and labor; the leakage protection device is saved, only one set of leakage protection device is needed for multiple charging guns; the networking device is saved, only one set of networking device is needed for multiple charging guns; the network overhead is saved, only one networking heartbeat packet is needed for multiple charging guns. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of a centralized AC charging pile for automobiles provided by an embodiment of the present invention.

[0017] Figure 2 It is a flowchart of a charging control method for a centralized AC charging pile for automobiles provided by an embodiment of the present invention; Figure 3 It is the electrical principle of the main control circuit provided by an embodiment of the present invention Figure 1 。

[0018] Figure 4 It is the electrical principle of the main control circuit provided by an embodiment of the present invention Figure 2 。

[0019] Figure 5 It is the electrical principle of the main control circuit provided by an embodiment of the present invention Figure 3 。

[0020] Figure 6 It is the electrical schematic diagram of the CP signal processing circuit provided by an embodiment of the present invention.

[0021] Figure 7 It is the electrical schematic diagram of the CP feedback circuit provided by an embodiment of the present invention.

[0022] Figure 8 It is the electrical schematic diagram of the AC to DV circuit provided by an embodiment of the present invention.

[0023] Figure 9 It is the electrical schematic diagram of the -12V generation circuit provided by an embodiment of the present invention.

[0024] Figure 10 It is the electrical schematic diagram of the DC buck circuit provided by an embodiment of the present invention.

[0025] Figure 11 It is the electrical schematic diagram of the ground detection circuit provided by an embodiment of the present invention.

[0026] Figure 12 It is the electrical schematic diagram of the relay control circuit provided by an embodiment of the present invention.

[0027] Figure 13 is the electrical schematic diagram of the power measurement and AC type leakage protection circuit provided by the embodiments of the present invention.

[0028] Figure 14 is the overall electrical principle block diagram of the charging pile control main board provided by the embodiments of the present invention. Detailed implementation manners

[0029] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals indicate the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0030] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the present invention. In addition, in the description of the present invention, the meaning of "a plurality of" is two or more unless otherwise specifically defined.

[0031] The present invention discloses a centralized automotive AC charging pile, which integrates a multi-pile control board, leakage detection, metering, a low-voltage DC power supply, etc., to achieve the effect that one charging pile can charge multiple vehicles simultaneously.

[0032] As Figure 1 shown, the centralized automotive AC charging pile provided by the present invention includes a charging pile box body, which has an accommodation space inside for centrally arranging the control main board of the charging system of the charging pile and is arranged on the control main board; An inlet port, which is an inlet port provided on the charging pile box body for introducing single-phase electricity or three-phase electricity into the charging pile box body through an inlet cable and connecting it to an air switch. The wire diameter of the inlet cable is determined according to the specific installation quantity of the charging line guns to be equipped for the actual charging pile to meet different power requirements; A control main board, which is arranged inside the charging pile box body for regulating the entire charging system. It controls the charging guidance, charging protection, charging start and stop of one-way AC input and multi-way charging line gun AC output of the charging pile through a main control chip, and sets a set of leakage protection, networking equipment and gun line temperature detection on the control main board to cooperate with the main control chip to monitor and network the multi-way charging line guns to realize the control of a set of charging system in the charging pile for multi-way output charging line guns; Charging gun assembly: Multiple charging cable guns are led out from the independent control main board of the charging pile, and each charging cable gun independently provides AC charging service for a vehicle; Gun seat, with each end of the gun line corresponding to a gun seat, and a unique QR code is screen-printed on the surface of the gun seat. Users can start the charging service of the corresponding charging gun by scanning the QR code.

[0033] The following modules are respectively set on the control main board, including Charging guidance control module: An independent control and guidance signal generation and detection device is equipped for each charging gun, which is used to generate and receive charging guidance signals to realize charging interaction between the charging pile and the vehicle; Power supply control module: Two or three relays are configured for each charging gun to control the on-off of the power supply between the charging gun and the power source; Temperature monitoring module: A gun line temperature detection device is set corresponding to each charging gun to monitor the gun line temperature in real time to ensure charging safety; Electricity metering module: An electricity metering device is equipped for each charging gun to accurately measure the charging electricity of each charging gun and perform billing processing; Communication module: It includes a set of networking devices, which are used to interact with the background server for data to realize remote monitoring and management; Leakage protection module: It includes a set of leakage protection devices to monitor and protect the leakage situation of the entire charging pile.

[0034] The centralized AC charging pile for vehicles also includes: Power control component, which is used to control the on-off of the power supply of the entire charging pile and has overload and short-circuit protection functions; Grounding component: It is provided with a grounding bar, which connects the charging gun, the control main board and the protection box to ensure electrical safety; Electrical connection component: It includes an output wiring point and a gun temperature wiring point. The output wiring point is used to connect the charging gun and the control main board to realize power transmission; the gun temperature wiring point is used to connect the gun line temperature detection device and the charging gun to transmit temperature signals; CP signal connection component: A CP wiring point is set to connect the control and guidance signal generation and detection device and the charging gun to realize the transmission and interaction of CP signals.

[0035] The charging guidance control module is composed of a main control chip. The main control chip is used to generate and monitor CP signals, monitor protection devices, communicate with the background server through networking devices, and control the on-off of the relay according to CP signals, protection signals and background data; The main control chip has the following functions: Signal processing function: Generate and monitor CP signals in real time, and judge the charging status according to signal changes; Protection monitoring function: Real-time monitor protection signals such as leakage and overheating to ensure the safety of the charging process; Communication control function: Communicate with the background server through the communication module, receive server instructions and upload the charging pile status data, and control the on / off of the relay according to the CP signal, protection signal and server data; Billing management function: During the vehicle charging process, monitor the data of the power metering device in real time and perform accurate metering and billing processing.

[0036] The control main board also includes: AC to DC circuit, used to convert 220V AC into 12V DC to provide a stable DC power supply for the control main board and other functional modules; -12V generation circuit, used to generate -12V voltage to provide the required power supply for the processing and transmission of CP signals; DC buck circuit, used to step down 12V DC to 4.2V, and 4.2V supplies power to the main control chip and related circuit modules with low voltage requirements; Grounding detection circuit, used to detect the grounding status of the charging pile in real time and send out protection signals in time when the grounding is abnormal; Relay control circuit, used to control the opening and closing of the relay according to the instructions of the main control chip to realize the on / off control between 220V AC and the vehicle; Power metering and protection circuit, with a power metering and protection circuit unit corresponding to each charging gun, realizing functions such as charging power metering and current calculation, and having overvoltage, undervoltage, overcurrent, and leakage protection functions; AC type leakage protection is configured as required, and each charging pile needs 1. This circuit can provide overvoltage / undervoltage / overcurrent / leakage protection.

[0037] Main control circuit, providing the control and monitoring capabilities of external devices and being responsible for networking at the same time.

[0038] CP signal processing circuit, including a CP signal generation circuit and a CP feedback circuit. The CP signal generation circuit converts the PWM signal sent by the main control chip into a CP signal that meets the standard, with one path configured for each gun; CP feedback circuit, used to feedback the real-time change of the CP signal fed back from the vehicle end to the main control chip, also with one path configured for each gun.

[0039] After the 220V mains power supply enters the control main board, low-voltage direct current is obtained by the AC to DC circuit for each functional module to work.

[0040] After the main control chip is powered on, it boots up automatically, enters the protection detection, voltage and current monitoring, connects to the network and generates a CP signal, while monitoring the status of the CP signal. When the user inserts the charging gun, the corresponding CP signal changes. The main control chip monitors whether the CP status meets the charging requirements through the CP feedback unit. If it meets the requirements, it waits for the server to send a start charging instruction (the user scans the code and the server authenticates). If it does not meet the requirements, it notifies the user to exit the charging through lights or other means. After the charging pile receives the start charging instruction, it closes the corresponding relay, and the 220V alternating current reaches the vehicle OBC through the relay, charging cable, and charging gun head. At the same time, the corresponding metering unit starts to work, records the electricity consumed during the entire charging process, and transmits it to the main control for billing. If the charging pile receives a stop charging instruction from the server or detects that the CP does not meet the charging requirements or a protection alarm occurs, it disconnects this relay to end the charging of this gun.

[0041] The charging system of the centralized AC charging pile for vehicles is installed in a waterproof and fireproof box, and alternating current is introduced through the incoming line port by the commercial power. The wire diameter of the incoming line is determined according to the actual number of charging guns installed. The charging system includes a control main board, which is responsible for controlling the charging guidance, charging protection, charging start and stop, etc. of multiple charging guns. On the control main board, a device for generating and detecting the control guidance signal is equipped for each charging gun. The control main board is equipped with two or three relays for each charging gun, and the relays are responsible for the on and off of the power supply for each charging gun. Two relays are equipped for single-phase charging guns, and three relays are equipped for three-phase charging guns. On the control main board, a gun line temperature detection device is also equipped for each charging gun, a power metering device is equipped for each charging gun, a set of networking equipment is equipped, and a leakage protection device is equipped on the control main board to be responsible for the leakage monitoring of the entire charging pile; the charging pile can be connected to multiple charging gun lines, and each charging gun line can provide AC charging services for one vehicle. Each charging gun line is equipped with a gun seat, and the QR code of this gun is silk-screened on the gun seat. The user can start the charging of this gun by scanning the QR code.

[0042] The charging pile consists of a mains power inlet, an air switch, a leakage protection device, a housing, a control main board, a main control chip, a relay, a CP connection point, a metering device, multiple charging gun cables, a grounding bar, an output connection point, a gun temperature connection point, and a networking device. The air switch, leakage protection device, control main board, main control chip, relay, CP connection point, metering device, grounding bar, output connection point, gun temperature connection point, and networking device are all placed inside the housing, and the housing provides a waterproof and fireproof environment. The mains power passes through the inlet on the housing and is connected to the air switch, and then through the air switch to the control main board. On the control main board, there are respectively a main control chip, a relay, a metering device, a networking device, and connection points. The main control chip generates and monitors CP, monitors the protection device, communicates with the background server through the networking device, and controls the on / off of the relay according to the CP signal, protection (leakage, over-temperature, etc.) signals, and background data. After the vehicle starts charging, the corresponding metering device needs to be monitored to perform metering and billing processing. The charging gun cable passes through the housing and is connected to the charging pile through the CP connection point, grounding bar, output connection point, and gun temperature connection point. The external charging gun connects the vehicle and the charging pile. The user scans the QR code corresponding to the gun cable. After scanning, the applet or app sends the pile number to the background server. The server checks the status of the charging pile and the user's permissions. If the check passes, charging is started, the corresponding relay in the pile is turned on, and the OBC starts charging the battery.

[0043] Another object of the present invention is to provide a charging control method for a centralized AC charging pile for vehicles. The charging control method includes the following steps: Step S1: After the 220V power supply enters the main board, a low-voltage direct current is obtained by the AC-DC conversion circuit for the operation of each functional module. After the main control is powered on, it boots up automatically, initializes the system parameters, starts the protection detection program, monitors the voltage and current data in real time, establishes a network connection with the background server at the same time, generates a CP signal, and starts monitoring the status of the CP signal. In this step, it also includes: a power supply startup step, where the 220V mains power is connected through the inlet, passes through the air switch, and enters the control main board. The AC-DC conversion circuit converts 220V alternating current into 12V direct current to supply power to each module; the -12V generation circuit outputs -12V voltage for the CP signal; the DC bucking circuit buckles the 12V direct current to 4.2V to supply power to the main control. An equipment self-check step: After the main control chip is powered on, it initializes the internal registers, sets parameters such as interrupt vectors, etc.; starts the grounding detection circuit to check the grounding status of the charging pile. If the grounding is abnormal, it sends a fault message to the background server through the networking device, and at the same time displays a fault prompt locally on the charging pile to prevent subsequent charging operations. Network connection and CP signal preparation steps: The networked device initializes the network connection, attempts to establish a TCP / IP connection with the background server, and reconnects at a set time interval if the connection fails; controls the guiding signal generating device to generate an initial CP signal, and the parameters such as the amplitude and frequency of the CP signal meet the national standard requirements, and the main control chip starts to monitor the CP signal status in real time.

[0044] Step S2: After the user inserts the charging gun, the corresponding CP signal changes. The main control monitors the CP status through the CP feedback circuit and determines whether it meets the charging requirements according to the preset charging conditions; if not, immediately inform the user to exit the charging through methods such as light flashing and voice prompts; if it meets the requirements, enter the waiting for charging instruction state; in this step, it also includes: charging gun connection detection step, the user inserts the charging gun into the vehicle charging interface, and the connection action will change the CP signal line state; the guiding signal detection device captures the change of the CP signal and feeds it back to the main control chip through the CP feedback circuit; Charging condition judgment step: The main control chip analyzes the fed-back CP signal according to the preset charging conditions (such as the CP signal amplitude within the specified range, normal vehicle communication handshake, etc.). If the CP signal parameters are abnormal, the main control chip controls the indicator light of the charging pile to flash and the buzzer to sound, prompting the user that the charging gun connection is abnormal or the vehicle does not match, and the charging gun needs to be reinserted or replaced; if the CP signal meets the requirements, enter the waiting for charging instruction state.

[0045] Step S3: The charging pile receives the start charging instruction sent by the background server based on the user's scanning code information through the networked device. After receiving the instruction, the main control controls the corresponding relay to close according to the instruction information, so that the 220V alternating current is transmitted to the vehicle OBC through the relay, gun line, and gun head in sequence to officially start the charging process; at the same time, start the corresponding power metering device to start recording the charging power; in this step, it also includes: scanning code information upload step, the user scans the QR code on the gun seat, and the small program or APP obtains the pile number and user identity information and sends this information to the background server through the network. The server checks the charging pile status and user permissions. If the check passes, the charging is started; the corresponding relay in the pile is connected, and the OBC starts to charge the battery; Permissions and status verification step: After receiving the request, the background server queries the database to verify the user's permissions (such as whether the account balance is sufficient, whether there is an overdue record, whether there are charging restrictions, etc.), and at the same time checks the charging pile status (whether it is idle, whether there is a fault, etc.). If the user's permissions are insufficient or the charging pile status is abnormal, the server returns an error message to the small program or APP, informing the user that charging cannot be performed; if the verification passes, the server sends a start charging instruction containing information such as the user ID, charging amount limit, and power limit to the charging pile; Charging startup steps: After the charging pile networking device receives an instruction, it parses the instruction data and transfers it to the main control chip. The main control chip controls the relay control circuit according to the instruction, closes the relay of the corresponding charging gun, and enables 220V alternating current to access the vehicle OBC through the relay, gun line, and gun head in sequence. At the same time, the main control chip sends a startup instruction to the power metering device to start recording the charging power.

[0046] Step S4: During the charging process, the main control continuously and real-time monitors the gun line temperature, voltage, current data, and the status of the CP signal. It obtains the gun line temperature through the gun line temperature detection device. If the temperature exceeds the safety threshold, it immediately activates the cooling measure or stops charging. It accurately measures the charging power using the power metering device and transmits the data to the main control in real-time. It continuously monitors the CP signal through the CP feedback circuit. If the CP signal is abnormal, it immediately stops charging. This step also includes: a temperature monitoring step. The gun line temperature detection device collects gun line temperature data every certain period (such as 10 seconds) and transmits the data to the main control chip through communication protocols such as SPI or I2C. The main control chip compares the real-time temperature with the preset safety threshold (for example, 75°C). If the temperature exceeds the threshold, the main control chip first controls the relay control circuit to cut off the power supply of the gun line and stop charging. Then it starts the cooling fan and simultaneously sends a temperature anomaly alarm message to the background server through the networking device, and displays a high temperature reminder locally on the charging pile to remind the user to pay attention to safety. Power and current monitoring step: The metering unit in the power metering and protection circuit accumulates the charging power in real-time based on the power metering chip, and the current detection unit monitors the charging current through a sampling resistor or current transformer. The main control chip periodically reads the power and current data. If the current exceeds the preset overcurrent threshold (such as 16A, set according to the rated current of the charging pile), the main control chip immediately controls the relay to disconnect and stop charging, and informs the user of the overcurrent fault through an indicator light and voice prompt. At the same time, it uploads the overcurrent data to the background server for subsequent analysis. CP signal monitoring step: During the charging process, the main control chip continuously monitors the CP signal through the CP feedback circuit. If the CP signal shows abnormal fluctuations (such as amplitude mutation, frequency anomaly), the main control chip determines that the vehicle charging status is abnormal, immediately controls the relay to cut off the charging circuit and stop charging, and reports the CP signal abnormality to the background server through the networking device, prompting the user to check the vehicle charging interface or contact the customer service. Leakage monitoring step: The leakage protection device continuously monitors the residual current in the charging pile circuit, using detection means such as a zero-sequence current transformer. Once it detects that the leakage current exceeds the set threshold (such as 30mA), the leakage protection device quickly acts, cuts off all relays, stops the power supply of the entire charging pile, and simultaneously triggers a local audible and visual alarm to inform the user of the leakage danger. It also sends a leakage fault message to the background server through the networking device for timely repair.

[0047] Step S5: When the charging pile receives the stop charging instruction sent by the server, or the main controller detects that the CP signal does not meet the charging requirements, or protection alarms such as overvoltage, undervoltage, overcurrent, and leakage occur, the main controller quickly controls the relay of the corresponding gun line to be disconnected, cuts off the AC power supply, ends the charging process of this gun, and uploads the final charging power data to the background server for billing and settlement. This step also includes: an end condition judgment step. When any of the following conditions is met, it is determined that the charging ends: the charging pile receives the stop charging instruction sent by the background server (such as the user actively ending the charging on the APP, reaching the preset charging amount or power); the main control chip detects that the CP signal does not meet the charging requirements; protection alarms such as overvoltage, undervoltage, overcurrent, and leakage occur. Charging stop operation step: After receiving the charging end signal, the main control chip controls the relay control circuit to disconnect the relay of the corresponding gun line and cut off the 220V AC power supply. At the same time, the main control chip sends a stop metering instruction to the power metering device to obtain the final charging power data. Data upload and prompt step: The main control chip uploads information such as the final charging power data, charging duration, and charging fee (if already settled) to the background server through the networking device for billing and data statistics. The indicator light of the charging pile returns to the initial state, and there may be a voice prompt "Charging ended" to inform the user that the charging is completed, and the user can unplug the gun and leave.

[0048] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A centralized automobile AC charging pile, characterized in that: The centralized automobile AC charging pile includes The charging pile box has a storage space inside for centrally placing the charging system of the charging pile; The inlet is located on the charging pile box and is used to introduce single-phase or three-phase electricity into the charging pile box through the inlet cable and connect it to the air switch. The diameter of the inlet cable is determined according to the specific number of charging wire guns to be equipped on the actual charging pile to meet different power requirements; The control mainboard is arranged in the charging pile box, and is used to control the entire charging system. The main control chip controls the charging pile's one-way AC input and the charging guidance, charging protection, and charging start and stop of the multiple-way charging line guns' AC outputs. A set of leakage protection, networking equipment, and gun line temperature detection are arranged on the control mainboard to cooperate with the main control chip to monitor and network the multiple-way charging line guns, so that a set of charging systems in the charging pile can control the multiple-way output charging line guns; Charging cable gun assembly: Multiple charging cable guns are led out from the independent control mainboard of the charging pile, and each charging cable gun independently provides AC charging service for one car; Charging gun holder, each charging line gun has a corresponding charging gun holder at the end, and an exclusive QR code is silk-screened on the surface of the charging gun holder. Users can activate the charging service of the corresponding charging line gun by scanning the QR code.

2. The centralized automobile AC charging pile according to claim 1, characterized in that: The control mainboard is integrated with the following modules: Charging guidance control module: Each charging gun is equipped with an independent control guidance signal generation and detection device, which is used to generate and receive charging guidance signals to realize charging interaction between the charging pile and the car; Power supply control module: two or three relays are configured for each charging gun to control the power supply between the charging gun and the power supply; Temperature monitoring module: A gun line temperature detection device is set for each charging gun to monitor the gun line temperature in real time to ensure charging safety; Power metering module: Each charging gun is equipped with a power metering device to accurately measure the charging power of each charging gun and perform billing processing; Communication module: includes a set of networking equipment for data interaction with the backend server to achieve remote monitoring and management; Leakage protection module: includes a set of leakage protection devices to monitor and protect the leakage of the entire charging pile.

3. The centralized automobile AC charging pile according to claim 2, characterized in that: The centralized automobile AC charging pile also includes: The power control component is used to control the power on and off of the entire charging pile, and has overload and short-circuit protection functions; Grounding assembly: equipped with a grounding bar to connect the charging gun, control mainboard and protective box to ensure electrical safety; Electrical connection components: including output wiring points and gun temperature wiring points. The output wiring points are used to connect the charging gun and the control mainboard to achieve power transmission; the gun temperature wiring points are used to connect the gun line temperature detection device and the charging gun to transmit temperature signals. CP signal connection component: Set the CP wiring point, connect the control guide signal generation, detection device and charging gun, and realize the transmission and interaction of CP signals.

4. The centralized automobile AC charging pile according to claim 3, characterized in that: The charging guidance control module is composed of a main control chip, which is used to generate and monitor CP signals, monitor protection devices, communicate with the background server through a networking device, and control the on and off of the relay according to the CP signal, protection signal and background data; the main control chip has the following functions: Signal processing function: Generate and monitor CP signal in real time, and judge charging status based on signal changes; Protection monitoring function: real-time monitoring of protection signals such as leakage and over-temperature to ensure the safety of the charging process; Communication control function: communicate with the background server through the communication module, receive server instructions and upload charging pile status data, and control the on and off of the relay according to the CP signal, protection signal and server data; Billing management function: During the car charging process, the power metering device data is monitored in real time to perform accurate metering and billing processing.

5. The centralized automobile AC charging pile according to claim 4, characterized in that: The control mainboard also includes: AC to DC circuit, used to convert 220V AC power into 12V DC power, providing a stable DC power supply for the control mainboard and other functional modules; -12V generating circuit, used to output -12V voltage, to provide the required power for CP signal processing and transmission; DC step-down circuit, used to step down 12V DC to 4.2V, 4.2V is used to power the main control chip and related circuit modules with low voltage requirements; The grounding detection circuit is used to detect the grounding status of the charging pile in real time and send a protection signal in time when the grounding is abnormal; The relay control circuit is used to control the opening and closing of the relay according to the instructions of the main control chip to realize the on-off control between the 220V AC power and the car; The power metering and protection circuit is used for each charging gun to correspond to a power metering and protection circuit unit, realizing the charging power metering and current calculation functions, and having overvoltage, low voltage, overcurrent and leakage protection functions; The CP signal processing circuit includes a CP signal generating circuit and a CP feedback circuit. The CP signal generating circuit converts the PWM signal sent by the main control chip into a CP signal that meets the standard. Each gun is configured with one circuit. The CP feedback circuit is used to feed back the CP signal changes fed back from the vehicle end to the main control chip in real time, and each gun is also equipped with one circuit.

6. A charging control method for a centralized automobile AC charging pile, characterized in that: The charging control method of the centralized automobile AC charging pile comprises the following steps: System initialization steps: After the 220V power supply enters the mainboard, the AC to DC circuit obtains low-voltage direct current to supply each functional module; after the main control is powered on, it automatically starts up, initializes system parameters, starts the protection detection program, monitors voltage and current data in real time, establishes a network connection with the background server, generates a CP signal, and starts monitoring the CP signal status; In the charging preparation detection step, after the user plugs in the gun, the corresponding CP signal changes. The main control monitors the CP status through the CP feedback circuit and determines whether it meets the charging requirements based on the preset charging conditions. If it does not meet the requirements, the user is immediately informed to exit charging through flashing lights, voice prompts, etc. If it meets the requirements, it enters the waiting state for charging instructions. Charging authorization and start-up steps: The charging pile receives the start charging instruction issued by the background server based on the user's scan code information through the networking device. After receiving the instruction, the main control controls the corresponding relay to close according to the instruction information, so that the 220V AC power is transmitted to the car OBC through the relay, gun line, and gun head in sequence, and the charging process is officially started; at the same time, the corresponding power metering device is started to start recording the charging power; Charging process monitoring steps: During the charging process, the main control continuously monitors the gun line temperature, voltage, current data and CP signal status in real time, obtains the gun line temperature through the gun line temperature detection device, and immediately starts cooling measures or stops charging if the temperature exceeds the safety threshold; uses the power metering device to accurately measure the charging power and transmits the data to the main control in real time; continuously monitors the CP signal through the CP feedback circuit, and immediately stops charging if the CP signal is abnormal; Charging end control step: when the charging pile receives the stop charging command sent by the server, or the main control detects that the CP signal does not meet the charging requirements, or an overvoltage, low voltage, overcurrent, leakage or other protection alarm occurs, the main control quickly controls the relay to disconnect the corresponding gun line, cuts off the AC power supply, ends the charging process of this gun, and uploads the final charging power data to the background server for billing and settlement.

7. The charging control method of a centralized automobile AC charging pile according to claim 6, characterized in that: The system initialization step includes the following steps: The power supply startup steps are as follows: 220V mains power is connected through the line inlet and enters the control mainboard through the air switch. The AC to DC circuit converts 220V AC power into 12V DC power to power each module; the -12V generating circuit outputs -12V voltage for CP signal; the DC step-down circuit steps down 12V DC power to 4.2V to power the main control; The device self-checking steps are as follows: after the main control chip is turned on, the internal registers are initialized, and the interrupt vector and other parameters are set; the grounding detection circuit is started to check the grounding condition of the charging pile. If the grounding is abnormal, the fault information is sent to the background server through the networked device, and the fault prompt is displayed locally on the charging pile to prevent subsequent charging operations; In the steps of preparing for networking and CP signal, the networking device initializes the network connection and tries to establish a TCP / IP connection with the background server. If the connection fails, it will reconnect at the set time interval. The control guidance signal generating device generates the initial CP signal. The CP signal amplitude, frequency and other parameters meet the national standard requirements. The main control chip starts to monitor the CP signal status in real time.

8. The charging control method of the centralized automobile AC charging pile according to claim 7, characterized in that: The charging preparation detection step comprises the following steps: In the charging gun connection detection step, the user inserts the charging gun into the car charging port. The connection action will change the CP signal line state; the control guidance signal detection device captures the CP signal change and feeds it back to the main control chip through the CP feedback circuit; In the charging condition judgment step, the main control chip analyzes the feedback CP signal according to the preset charging conditions. If the CP signal parameters are abnormal, the main control chip controls the indicator light of the charging pile to flash and the buzzer to sound, prompting the user that the charging gun is abnormally connected or the vehicle does not match, and the charging gun needs to be re-plugged or replaced; if the CP signal meets the requirements, it enters the waiting state for charging instructions.

9. The charging control method of a centralized automobile AC charging pile according to claim 8, characterized in that: The charging authorization and start step includes the following steps: Scan code information upload step: the user scans the QR code on the gun mount, and the mini program or APP obtains the stake number and user identity information, and sends this information to the backend server through the network; Permission and status verification step: After receiving the request, the backend server queries the database to verify the user's permissions and checks the status of the charging pile. If the user does not have sufficient permissions or the charging pile is in an abnormal state, the server returns an error message to the mini program or APP to inform the user that charging is not possible. If the verification is successful, the server sends a start charging instruction to the charging pile containing information such as the user ID, charging amount limit, and power limit. Charging start step: after receiving the instruction, the charging pile networking device parses the instruction data and passes it to the main control chip. The main control chip controls the relay control circuit according to the instruction, closes the relay of the corresponding charging gun, and connects the 220V AC power to the car OBC through the relay, gun line, and gun head in sequence; at the same time, the main control chip sends a start instruction to the power metering device to start recording the charging power; The charging process monitoring step comprises the following steps: Temperature monitoring step: the gun line temperature detection device collects gun line temperature data at regular intervals and transmits the data to the main control chip through communication protocols such as SPI or I2C; the main control chip compares the real-time temperature with the preset safety threshold. If the temperature exceeds the threshold, the main control chip first controls the relay control circuit to cut off the power supply of the gun line and stop charging; then the cooling fan is started, and at the same time, the temperature abnormality alarm information is sent to the background server through the networked device, and the high temperature prompt is displayed locally on the charging pile to remind the user to pay attention to safety; The power and current monitoring steps are as follows: the metering unit in the power metering and protection circuit accumulates the charging power in real time based on the electric energy metering chip, and the current detection unit monitors the charging current through a sampling resistor or a current transformer; the main control chip periodically reads the power and current data. If the current exceeds the preset overcurrent threshold, the main control chip immediately controls the relay to disconnect, stops charging, and informs the user of the overcurrent fault through an indicator light and voice prompt; at the same time, the overcurrent data is uploaded to the background server for subsequent analysis; CP signal monitoring step: During the charging process, the main control chip continuously monitors the CP signal through the CP feedback circuit; if the CP signal fluctuates abnormally, the main control chip determines that the vehicle charging state is abnormal, and immediately controls the relay to cut off the charging circuit, stops charging, and reports the CP signal abnormality to the background server through the networked device, prompting the user to check the vehicle charging interface or contact customer service; Leakage monitoring step: The leakage protection device monitors the residual current in the charging pile circuit in real time, using detection methods such as zero-sequence current transformers; once it detects that the leakage current exceeds the set threshold, the leakage protection device will act quickly, cut off all relays, stop the power supply of the entire charging pile, and trigger a local sound and light alarm to inform the user of the leakage danger; and send leakage fault information to the background server through the networked device for timely maintenance; The charging end control step includes the following steps: The end condition judgment step is to determine that charging is ended when any of the following conditions are met: the charging pile receives a stop charging instruction issued by the background server; the main control chip detects that the CP signal does not meet the charging requirements; an overvoltage, low voltage, overcurrent, leakage and other protection alarms occur; Charging stop operation steps: after the main control chip receives the charging end signal, it controls the relay control circuit to disconnect the relay of the corresponding gun line and cut off the 220V AC power supply; at the same time, the main control chip sends a stop measurement instruction to the power metering device to obtain the final charging power data; In the data upload and prompt steps, the main control chip uploads the final charging power data, charging time, charging cost and other information to the background server through the networked device for billing settlement and data statistics; the indicator light of the charging pile returns to the initial state, which may be accompanied by a voice prompt "charging completed", informing the user that charging is complete and the user can draw his gun and leave.

10. The charging control method of a centralized automobile AC charging pile according to claim 9, characterized in that: The step of uploading the scanned code information also includes The server checks the status of the charging pile and user permissions, and starts charging if the check passes; The corresponding relay in the pile is turned on, and the OBC starts charging the battery.

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