Raspberry Pi industrial control management device based on embedded webpage server

Abstract

The utility model discloses Raspberry Pi industrial control management equipment based on an embedded webpage server, belongs to the field of intelligent industrial automation control, and aims to solve the problems that reliability design is not carried out on a power module in hardware in the conventional industrial control management equipment, accidents often occur during wiring operation of the power module or in severe weather, and short circuit is caused; therefore, the peripheral circuit of the sensor is short-circuited, and the computer mainboard is damaged and burnt out. The double-path isolation power supply module comprises a power supply input filter circuit, two power supply anti-surge and anti-overcurrent protection circuits, two DC-DC circuits and a power supply anti-backflow module; the output end of the power supply input filter circuit is connected with the input ends of the two power supply anti-surge and anti-overcurrent protection circuits. Each path of relay module is connected with an optocoupler, each optocoupler is connected with the controller through a connector, and each path of relay module is used for relay output to realize control, and sends a control instruction of an intelligent terminal to the controller for processing. The system is used for automatic industrial Internet of Things control.

Description

Technical Field

[0001] The utility model belongs to the fields of intelligent industrial automation control, industrial process control, etc., and specifically relates to a Raspberry Pi industrial control management device based on an embedded web server. Background Art

[0002] With the development of computer technology, embedded systems have become an important part of the computer field. Broadly speaking, any dedicated hardware and software system with a microprocessor can be called an embedded system. The so-called embedded device refers to a device or equipment that has computer functions but is not called a computer, including almost all circuit devices in our cycle: PDA, mobile phone set-top box, car, microwave oven, elevator, security system, vending machine, medical equipment, ATM, etc. Embedded systems can achieve mutual connection through various wireless forms (such as WAP, BlueTooth, etc.) and wired forms (TCP / IP, PPP, etc.) of network connection methods. Therefore, they are very vital in the network communication market. Now people's dependence on Internet applications is increasing, which also promotes the growth of embedded technology. The development of information appliances also provides space for embedded Internet technology, such as Internet-oriented information refrigerators. The characteristics of this kind of information appliance are low price, powerful software functions, full support for Internet access, software upgrades through the network, and effective protection of user investment.

[0003] Embedded Internet technology mainly includes sensor technology, communication technology, computer technology and integrated circuit technology. The existing equipment control system is generally carried out through a dedicated communication line, and its communication media, communication protocols, related software and hardware are all dedicated. The development of Internet technology has changed the remote control and management methods of embedded devices. There is no need for dedicated communication lines, and the transmitted information is not limited to data signals, but also sounds and images. The most important thing is that its communication protocol is standard and open. With the development of Web technology, the current form of information expression has almost changed, and many applications are based on Web technology. Due to the standard uniformity of HTML language, as long as there is a micro server in the embedded device, any Web browser can be used to receive and send information. Therefore, how to design this special Web server and how to install the Web server in the embedded device have become the development and research direction of embedded Web servers.

[0004] The utility model patent document with document number CN220526221U (authorization announcement number CN220526221U authorization announcement date is February 23, 2014) discloses an industrial control management device, which at least includes a control module, an audio module, a network transmission module, a multimedia transmission module, a connector module and a switch module, the control module is connected to the audio module, the network transmission module, the multimedia transmission module, the connector module and the switch module respectively, the network transmission module at least includes a PCIe interface, a CAN interface and a USB interface, the PCIe interface is used to connect the LoRa module, the LTE module and the solid state drive, the CAN interface is used to transmit through the CAN bus, and the control module can be accessed through LTE technology, Ethernet and LoRa wireless technology, and the solid state drive can also be accessed, which meets the needs of customers, improves the software development system based on Raspberry Pi, and can effectively reduce the threshold and time of software development, greatly optimizing the use of users. However, the utility model does not make a reliability design for the power module in the hardware, and the power module often has an accidental short circuit during wiring operation or in bad weather, thereby causing the sensor peripheral circuit to short circuit and the computer motherboard to be damaged and burned. Utility Model Content

[0005] The technical problem to be solved by the utility model is that the existing industrial control management equipment does not have a reliability design for the power module in the hardware, and an accident often occurs during the wiring operation of the power module or in bad weather, resulting in a short circuit, which in turn causes the sensor peripheral circuit to short-circuit and the computer mainboard to be damaged and burned.

[0006] The technical solution adopted by the utility model to solve the above technical problems is: a Raspberry Pi industrial control management device based on an embedded web server, wherein the Raspberry Pi industrial control management device is a universal network controller based on Raspberry Pi 4b to realize automated industrial Internet of Things control;

[0007] Its hardware includes Raspberry Pi 4b controller, 40PinGPIO connector, dual-channel isolated power module, 4 optocouplers, 4-channel relay module, 8-channel PWM module, UART (Universal Asynchronous Receiver / Transmitter), RS-485 level conversion chip, SPI (Serial Peripheral Interface), IIC (Serial Communication Bus);

[0008] The Raspberry Pi 4b controller has a two-way communication WIFI / Bluetooth interface, an RJ45 network port, a USB2.0 interface, a USB3.0 interface, a MIPI-DSI interface for an external display (one-way output), and a MIPI-CSI interface for an external camera (one-way input).

[0009] The dual-channel isolated power supply module includes a power input filter circuit, two power surge and overcurrent protection circuits, two DC-DC circuits (used to convert high-voltage DC into low-voltage DC), and a power backflow prevention module; the output end of the power input filter circuit is connected to the input end of the two power surge and overcurrent protection circuits, and the output end of each power surge and overcurrent protection circuit is connected to a corresponding DC-DC circuit; the low-voltage DC output end of a DC-DC circuit is connected to the power backflow prevention module, and the power backflow prevention module supplies power to the Raspberry Pi 4b controller through the 40PinGPIO connector, and the low-voltage DC output end of the other DC-DC circuit supplies power to the 4-channel relay module, the 8-channel PWM module, and the RS-485 level conversion chip at the same time.

[0010] Each relay module is connected to an optocoupler, and each optocoupler is connected to the Raspberry Pi 4b controller through a 40-pin GPIO connector. Each relay module is used for relay output to achieve control; 8-way PWM modules are connected to the Raspberry Pi 4b controller through a 40-pin GPIO connector, and each PWM module is used for PWM output to achieve control; UART, SPI, and IIC are connected to the Raspberry Pi 4b controller through a 40-pin GPIO connector, and UART interacts with the RS-485 level conversion chip. The RS-485 level conversion chip is used to connect sensors in the industrial control process;

[0011] The control instructions of the smart terminal are sent to the Raspberry Pi 4b controller through the WIFI / Bluetooth interface for processing, and the execution results (relay, PWM, sensor) are fed back; the USB2.0 interface and USB3.0 interface are used to connect peripherals.

[0012] Furthermore, the dual-channel isolated power supply module is: using an external 12V power supply, with two isolated power supplies; the first power supply first passes through the TPS2421-2DDA self-recovery electronic fuse chip, and then passes through the TPS5430DDAR, and the step-down DC-DC chip is converted to 5V to power the on-board relay and RS-485 communication module, and the 5V power supply passes through the TLV1117-33CDCYR linear voltage regulator chip to 3.3V for use by corresponding devices on the board; the second power supply first passes through the TPS2421-2DDA self-recovery electronic fuse chip, and then passes through the TPS5430DDAR, and the step-down DC-DC chip is converted to 5V, and then passes through two parallel LM66100DCKR ideal diode chips, and through the 40PinGPIO connector to separately power the Raspberry Pi 4b.

[0013] Furthermore, the power supply surge and overcurrent protection circuit (power supply overcurrent protection and surge protection) is mainly implemented through the TPS2421-2DDA self-recovery electronic fuse chip.

[0014] Furthermore, the power supply backflow prevention module (power supply backflow prevention protection) is mainly implemented by two LM66100DCKR ideal diode chips connected in parallel.

[0015] Furthermore, the relay module adopts an optocoupler relay circuit, which is electrically isolated by a TLP785GB optocoupler, and the isolation voltage is not less than 5000V. The relay adopts the Songle SRD series relay, which can meet the load requirements of 7A / 250VAC10A / 250VAC15A / 250VAC.

[0016] Furthermore, the PWM module is based on AOD4184A type NMOSFET to achieve large bandwidth 12VPWM output, drive low voltage load, and realize power regulation.

[0017] Furthermore, the UART and RS-485 level conversion chip constitute an RS-485 communication module.

[0018] The utility model has the following beneficial technical effects:

[0019] The dual power supply design is the inventive point of the utility model. The following aspects are fully considered when designing the power module: 1. Industrial automation sites often face complex operating environments. When wiring, especially when connecting the RS-485 connectors of the product and sensors, there are often virtual connections, overlaps, and foreign objects in the connectors, which can easily lead to short circuit faults. Therefore, an electronic fuse module is needed for protection, and because a self-recovery fuse module is selected, it only needs to eliminate the fault point to resume work, without restarting the power supply, simplifying the industrial site operation process. 2. Considering that the Raspberry Pi 4b operating system takes a long time to start up after power failure, the use of a dual-channel isolated power supply can avoid frequent restarts caused by controller wiring failures, save time, and help improve the stability of the operating system. 3. The dual-channel isolated power supply can isolate the power failure of the Raspberry Pi 4b from the controller baseboard, ensuring that other parts of the product will not be damaged due to a power failure of a certain component of the product, which can improve product reliability.

[0020] The utility model is applied to the industrial control system hardware of unattended remote equipment and its supporting Web server. The improvements of the utility model are all in the hardware, especially the reliability design of the power module in the hardware. This product is a universal network controller based on Raspberry Pi 4b, which is used for automated industrial Internet of Things control. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1It is the overall structural block diagram of the utility model (Raspberry Pi industrial control management device based on embedded web server); Figure 2 This is a circuit diagram of the power module in the utility model. Figure 7 The corresponding reference connection for the RaspberryPi4b controller in .

[0022] Figure 3 This is the power supply overcurrent protection and surge protection circuit diagram. Figure 4 This is the power backflow protection circuit diagram. Figure 5 This is the circuit diagram of the relay module. Figure 6 This is the circuit diagram of the PWM module. Figure 7 This is the circuit diagram of the Raspberry Pi 4b controller. Figure 8 This is the circuit diagram of the 8-channel PWM module. Fig. 9 This is the circuit diagram of the 4-way relay module. Fig.10 This is the circuit diagram of RS485. DETAILED DESCRIPTION

[0023] The following diagram is attached Figure 1-10 The implementation of this new model is described as follows:

[0024] The present invention (this product) is a universal network controller based on Raspberry Pi 4b, which is used for automated industrial Internet of Things control. The hardware of the product includes two-way isolated power supply module, power overcurrent protection and surge protection module, power backflow prevention module, computing and Ethernet communication module (4B controller, such as Figure 7 As shown), 40-pin GPIO connector, 4-way relay module, RS-485 communication module, 8-way PWM output module, such as Figure 1 and 2 As shown in the figure. In terms of software, the product runs on RaspberryPi OS, and all industrial control functions are implemented by the web server. The back end of the web server uses the web microframework Flask written in Python, and the front end uses CSS (Cascading Style Sheets, a standard style sheet language).

[0025] In terms of power supply, the product uses an external 12V power supply and has two isolated power supplies. The first power supply first passes through the TPS2421-2DDA self-recovery electronic fuse chip, and then passes through the TPS5430DDAR, and the step-down DC-DC chip is converted to 5V to power the on-board relays, RS-485 communication modules, etc. The 5V power supply is reduced to 3.3V by the TLV1117-33CDCYR linear voltage regulator chip for use by the corresponding devices on the board. The second power supply first passes through the TPS2421-2DDA self-recovery electronic fuse chip, and then passes through the TPS5430DDAR, and the step-down DC-DC chip is converted to 5V, and then passes through two parallel LM66100DCKR ideal diode chips, and then through the 40PinGPIO connector to power the Raspberry Pi 4b separately. Figure 2 shown.

[0026] Dual power supply design is the key point of power supply design, taking into account the following aspects: 1. Industrial automation sites often face complex operating environments. When wiring, especially when connecting the RS-485 connectors and sensors of the product, there are often virtual connections, overlaps, and foreign objects in the connectors, which can easily lead to short circuit faults. Therefore, an electronic fuse module is needed for protection, and because a self-recovery fuse module is selected, it only needs to eliminate the fault point to resume work, without restarting the power supply, simplifying the industrial site operation process. 2. Considering that the Raspberry Pi 4b operating system takes a long time to start up after power failure, the use of a dual-channel isolated power supply can avoid frequent restarts caused by controller wiring failures, save time, and help improve the stability of the operating system. 3. The dual-channel isolated power supply can isolate the power failure of the Raspberry Pi 4b and the controller baseboard, ensuring that other parts of the product will not be damaged due to power failure of a certain component of the product, which can improve product reliability.

[0027] Power supply overcurrent protection and surge protection are mainly achieved through the TPS2421-2DDA self-recovery electronic fuse chip, which further ensures the reliability and stability of the power supply. Figure 3 shown.

[0028] The power backflow protection is mainly realized by two LM66100DCKR ideal diode chips in parallel, which prevents the Raspberry Pi 4b from reversely supplying power to the product through the USB device when it is connected to an external USB device, causing the USB device to be overloaded and unable to work properly. This design also meets the relevant design requirements for power supply through GPIO in the official Raspberry Pi documentation, such as Figure 4 shown.

[0029] The relay module uses an optocoupler relay circuit and is electrically isolated through a TLP785GB optocoupler. The isolation voltage is not less than 5000V. The relay uses the Songle SRD series relay, which can meet the 7A / 250VAC10A / 250VAC15A / 250VAC load requirements. Figure 5 shown.

[0030] The PWM module, based on the AOD4184A NMOSFET, achieves a wide bandwidth 12V PWM output, which can drive low-voltage loads such as 12V DC pumps and achieve power regulation, such as Figure 6 shown.

[0031] The software is based on the existing technology, and the improvement of the utility model is only in the hardware circuit. The software product runs on Raspberry Pi OS, and all industrial control functions are implemented by the web server. The back end of the web server uses the web microframework Flask written in Python, and the front end uses CSS (Cascading Style Sheets, a standard style sheet language).

[0032] Flask is a small and lightweight framework that focuses on providing core functions and keeping it simple and easy to understand. It only provides basic components for web development, such as routing, sessions, request handling, etc. You can use Flask to quickly build a website or web service. The performance basically meets the needs of general web development, and it is flexible and scalable. In a real production environment, small projects are developed quickly and large projects are designed flexibly.

[0033] CSS (Cascading Style Sheets) is a standard style sheet language used to describe the presentation of a web page, such as the position, size, and color of web page elements. Its main function is to define the style of a web page, beautify the web page, and precisely control the position, font, color, background and other attributes of elements in the web page.

[0034] The combination of FLASK and CSS can meet most of the on-site industrial control needs. At the same time, its lightweight characteristics and minimal resource consumption are very beneficial for deployment on embedded platforms. Its easy-to-develop characteristics do not require personnel to master complex Web development capabilities and embedded development capabilities, and specific functions can be implemented under the existing industrial control server framework. Compared with the network controller implemented by traditional embedded development, the present invention can greatly shorten the development cycle. Developers do not need to have an in-depth understanding of the transport layer, network layer, link layer, and physical layer. They only need to focus on application layer development, and the requirements for personnel are also greatly reduced.

[0035] An application example of the present invention: a web server interface, taking an observatory dome control application scenario as an example.

Claims

1. A Raspberry Pi industrial control management device based on an embedded web server, characterized in that: The Raspberry Pi industrial control management device is a general network controller based on Raspberry Pi 4b to realize automated industrial Internet of Things control; Its hardware includes Raspberry Pi 4b controller, 40PinGPIO connector, dual-channel isolated power module, 4 optocouplers, 4-channel relay module, 8-channel PWM module, universal asynchronous receiver and transmitter UART, RS-485 level conversion chip, serial peripheral interface SPI, serial communication bus IIC; The Raspberry Pi 4b controller has a two-way communication WIFI / Bluetooth interface, an RJ45 network port, a USB2.0 interface, a USB3.0 interface, a MIPI-DSI unidirectional output interface for an external display, and a MIPI-CSI unidirectional input interface for an external camera. The dual-channel isolated power supply module includes a power input filter circuit, two power surge and overcurrent protection circuits, two DC-DC circuits for converting high-voltage DC into low-voltage DC, and a power backflow prevention module; The output end of the power input filter circuit is connected to the input end of two power supply surge protection and overcurrent protection circuits, and the output end of each power supply surge protection and overcurrent protection circuit is connected to a DC-DC circuit; The low-voltage DC output end of one DC-DC circuit is connected to the power backflow prevention module, which powers the Raspberry Pi 4b controller through the 40-pin GPIO connector. The low-voltage DC output end of the other DC-DC circuit is used to power the 4-way relay module, the 8-way PWM module, and the RS-485 level conversion chip at the same time. Each relay module is connected to an optocoupler, and each optocoupler is connected to the Raspberry Pi 4b controller through a 40-pin GPIO connector. Each relay module is used for relay output to achieve control; 8-way PWM modules are connected to the Raspberry Pi 4b controller through a 40-pin GPIO connector, and each PWM module is used for PWM output to achieve control; UART, SPI, and IIC are connected to the Raspberry Pi 4b controller through a 40-pin GPIO connector, and UART interacts with the RS-485 level conversion chip. The RS-485 level conversion chip is used to connect sensors in the industrial control process; The control instructions of the smart terminal are sent to the Raspberry Pi 4b controller through the WIFI / Bluetooth interface for processing, and the execution results are fed back to the relay, PWM, and sensor; the USB2.0 interface and USB3.0 interface are used to connect peripherals.

2. A Raspberry Pi industrial control management device based on an embedded web server according to claim 1, characterized in that: The dual-circuit isolated power supply module is: It uses an external 12V power supply and has two isolated power supplies. The first power supply first passes through the TPS2421-2DDA self-resettable electronic fuse chip, and then passes through the TPS5430DDAR. The step-down DC-DC chip is converted to 5V to power the on-board relay and RS-485 communication module. The 5V power supply is reduced to 3.3V by the TLV1117-33CDCYR linear voltage regulator chip for use by the corresponding devices on the board. The second power supply first passes through the TPS2421-2DDA self-resettable electronic fuse chip, and then passes through the TPS5430DDAR. The step-down DC-DC chip is converted to 5V, and then passes through two parallel LM66100DCKR ideal diode chips and the 40PinGPIO connector to power the Raspberry Pi 4b separately.

3. A Raspberry Pi industrial control management device based on an embedded web server according to claim 1 or 2, characterized in that: The power supply surge and overcurrent protection circuit is mainly realized by the TPS2421-2DDA self-recovery electronic fuse chip; the power supply surge and overcurrent protection circuit is used for power supply overcurrent protection and surge protection.

4. A Raspberry Pi industrial control management device based on an embedded web server according to claim 3, characterized in that: The power backflow prevention module is mainly implemented by two LM66100DCKR ideal diode chips connected in parallel; the power backflow prevention module is used for power backflow prevention protection.

5. A Raspberry Pi industrial control management device based on an embedded web server according to claim 4, characterized in that: The relay module adopts an optocoupler relay circuit and is electrically isolated by a TLP785GB optocoupler with an isolation voltage of no less than 5000V. The relay adopts the Songle SRD series relay and can meet the load requirements of 7A / 250VAC10A / 250VAC15A / 250VAC.

6. A Raspberry Pi industrial control management device based on an embedded web server according to claim 5, characterized in that: The PWM module is based on AOD4184A NMOSFET, realizes large-bandwidth 12V PWM output, drives low-voltage loads, and realizes power regulation.

7. A Raspberry Pi industrial control management device based on an embedded web server according to claim 1 or 2, characterized in that: The UART and RS-485 level conversion chip constitute an RS-485 communication module.

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