IoT monitoring system for natural gas compressors via GPRS wireless
With the development of new energy industry and the demand for energy saving and emission reduction, the use of natural gas has become a major direction of future energy. As the main equipment for natural gas applications, natural gas compressors have also seen a sharp increase in their applications. Due to the wide variety of natural gas compressors, complex structure and function, troubleshooting and maintenance are also complicated. At present, the manual inspection and on-site inspection are mainly used to carry out after-the-fact troubleshooting of CNG compressors; due to its wide distribution and numerous quantities, it is time-consuming and labor-intensive to use the method of manual troubleshooting on-site, and the maintenance cost is high; Larger lags cause inconvenience to users and cause certain economic losses. Real-time monitoring of the operating status and working parameters of natural gas compressors, timely correction, can avoid unnecessary losses; according to the compressor's operating records, predict its failures in advance, and reduce maintenance costs; record historical operating data and alarm information It is convenient for analyzing faults and improving the efficiency of equipment fault diagnosis and maintenance. Therefore, it is of great significance to study the natural gas compressor IoT monitoring system. In recent years, the development and application of wireless sensing and Internet of Things technology has become a hot topic. This paper connects a wide range of compressors to the Internet through GPRS wireless method, and researches and implements the IoT monitoring system of natural gas compressors, which is a natural gas compressor. Online detection, safe operation, and intelligent fault diagnosis provide reliable technical assurance. The network architecture of the CNG compressor IoT monitoring system is shown in Figure 1. The system consists of four major networks: equipment monitoring network, VPN local area network, mobile network and INTERNET. A plurality of CNG compressors constitute a equipment monitoring network, and each equipment monitoring network monitors the compressors in the network through its main monitor in real time, and manages and controls the real-time operating conditions and state parameters of each compressor. The on-site device monitoring host is wirelessly connected to the mobile NET and linked to the NET INTERNET via the physical link of the mobile NET. For a single compressor distributed in the field, it can be connected to the Internet directly via the mobile network without the equipment monitoring network. After the link is established, each equipment monitoring network (or compressor device) has a unique IP address on the NETINTERNET. According to the IP address, the remote monitoring computer exchanges data with the INTERNET through the VPN LAN to realize data access and control of the remote compressor. The CNG compressor IoT monitoring system is divided into four levels: device monitoring layer, data transmission layer, storage analysis layer, display and management layer. Each level uses a different system to form a complete and comprehensive network. As shown in Figure 2, each field compressor is connected to the equipment monitoring network through the field bus (485 bus, CAN bus, etc.), which is the equipment monitoring layer and is responsible for monitoring the real-time operating conditions and operating status of the compressor. The monitoring host of the compressor collects the data in the network node in real time and sends the collected data to the GPRS module. The data transmission layer is composed of a GPRS module, a transmitting base station, a GPRS backbone network, an INTERNET, and a VPN local area network, and uses TCP/IP protocol for data transmission between them. When the network establishes a connection, the GPRS module of the equipment monitoring network can be actively connected through the remote monitoring computer, or the server of the monitoring host can be actively searched through the GPRS module. Since the GPRS module usually assigns an IP address automatically by routing, and the server monitoring the host usually has a fixed IP address, this paper uses GPRS to actively find a way to monitor the computer server for network connection. After the GPRS module is powered on, it first searches for the transmitting base station nearby, registers it with the GPRS backbone network, and then connects to the server of the VNP LAN corresponding to its set IP address through the INTERNET. After receiving the real-time data of the on-site compressor, the server of the remote monitoring terminal runs the database management software, stores the data, and runs the expert system to analyze and manage the data, and the monitoring computer in the local area network runs the human-machine interface program to the server. The database is displayed, inquired, modified, and control commands are issued based on the results of the expert system and personal analysis to control the remote compressor. The system hardware consists of CNG compressor, controller, field bus, monitoring host, GPRS module, transmitting base station, network link, server and monitoring computer. Since the physical link of the network already exists, the user only needs to establish the equipment monitoring network of the compressor and the local area network of the monitoring computer and connect them to the INTERNET. After the corresponding parameters are configured, any computer connected to the INTERNET can be used as a monitoring computer to exchange data with any remote compressor to form a compressor Internet of Things. It can be seen that the establishment of the equipment monitoring network, the networking of the equipment monitoring layer, and the preparation of the remote monitoring program are the key to the compressor IoT monitoring system. There are many researches and applications on the establishment of equipment monitoring networks, so this is not detailed. The following is a detailed description of the networking of the equipment monitoring network and the preparation of the remote monitoring program. As shown in Figure 3, each compressor PLC collects field data in real time: current and voltage of the power supply, switch state of the valve, gas pressure of the inlet and outlet ports and the storage tank, intake and exhaust temperature, alarm information, operation buttons, lubrication status, and sewage discharge. Waiting; the monitoring host receives, sorts and stores the data collected by each compressor PLC. Then the data is transmitted to the GPRS module, and the GPRS module is sent to the remote server via the INTERNET using TCP/IP or UDP protocol. The program running in the monitoring host consists of three subroutines: network communication, data transmission and reception, and monitoring management. The network communication subroutine is responsible for sending a networking request to the GPRS, shaking hands with the remote host, and implementing the INTERNET connection of the equipment monitoring network. The data transceiver subroutine is responsible for receiving the monitoring data of the lower computer, storing and transmitting to the GPRS module end; when the remote control command is transmitted from the GPRS end, the transceiver subroutine receives the command and sends a command signal to the lower computer, for the CNG compressor Take control. The monitoring management word program is mainly responsible for managing the lower computer and analyzing and processing the real-time data. Three subroutines are run in the GPRS module: communication subroutine, communication protocol subroutine and wireless transceiving word program. The communication subroutine is responsible for data exchange with the monitoring host; the communication protocol subroutine is responsible for packaging the data from the monitoring host into a TCP/IP or UDP protocol format, or converting the data packet from the network into a fieldbus protocol format for data communication. The wireless transceiver subroutine is responsible for controlling the wireless transceiver chip, transmitting the data signal in the form of electromagnetic waves, and converting the received electromagnetic wave into a data signal for storage. Hf Driver,Compression Driver,Titanium Diaphragm Driver,Horn Drivers Guangzhou BMY Electronic Limited company , https://www.bmy-speakers.com
Figure 1 Network structure of CNG compressor IoT system 
Figure 2 Data transmission of CNG compressor IoT node 
Figure 3 Data transmission and reception of the field equipment monitoring network