The power system communication network is a crucial component of power system dispatch automation and enterprise management modernization. It comprises numerous network links, such as transmission networks, switching networks, and user terminals. Each network link includes many network elements, primarily microwave, carrier wave, fiber optic, spread spectrum, switches, and dispatching machines. These devices are distributed across various locations, including provincial and regional dispatch centers, power plants, and substations. 220 kV and below substations are trending towards integrated automation and unmanned operation, and the network contains a wide variety of equipment, each with its own management system. With the expansion of the power grid, the development of computer networks and communication technologies, and the continuous increase in power system information, the power system communication network is also constantly expanding. To ensure reliable system operation, real-time monitoring of the communication network, the operating status of each station and communication equipment, and the rapid and accurate transmission of various information and relevant data to the management center, enabling remote telemetry and control, managing communication network faults, and shortening maintenance downtime, it is necessary to establish a comprehensive communication network monitoring system to implement integrated management of the communication network. [b]1 System Overview[/b] The integrated monitoring system for the communication network monitors various operating communication equipment and has functions such as monitoring and controlling communication equipment, power supply, air conditioning, computer room environment, and auxiliary equipment such as power supply. For equipment in existing monitoring systems, it can be connected to the integrated monitoring system for the communication network through a standard communication port to achieve synchronous monitoring and control. 1.1 System Structure The system consists of a central station and branch stations. The central station is generally located in the regional dispatch center, and the branch stations are located in each substation. 1.1.1 Central Station The basic structure of the central station is a front-end communication unit + a back-end server + workstations, preferably using a bus-type Ethernet. Both the front-end communication unit and the back-end server can be configured with dual-machine hot backup. The number of workstations can be configured arbitrarily as needed and can support remote workstations. The system has high reliability, fast speed, good real-time performance, and can be expanded to achieve data sharing. If the system capacity is small, the central station can be completed by a single host. The basic structure of the central station is shown in Figure 1. [img=300,209]http://zszl.cepee.com/cepee_kjlw_pic/files/wx/hbdljs/2002-1/22-1.jpg[/img] 1.1.2 Substation The main equipment of the substation system consists of RTUs and various airborne units. One RTU is used as a tandem switch to manage multiple data acquisition units (called airborne units). Airborne units are front-end switching devices that convert various analog quantities, status quantities reflecting the operating status of communication equipment, and parameters reflecting the equipment and environment of the computer room, into analog or digital signals that can be directly interfaced with a computer, according to the technical requirements of communication. A bus structure is used between the RTU and each airborne unit. For intelligent devices within the station, they can be connected to the RTU through a protocol converter. The basic structure is shown in Figure 2. 1.2 System Functions The communication monitoring system should be able to monitor and control communication equipment, power supplies, air conditioning, and other equipment, and monitor the computer room environment. [img=350,175]http://zszl.cepee.com/cepee_kjlw_pic/files/wx/hbdljs/2002-1/23-1.jpg[/img] 1.2.1 Telemetry Function a. Analog Quantities: Acquires signals such as main levels, voltages, temperatures, and humidity from various communication equipment, communication power supplies, and communication equipment rooms. b. Status Quantities: Acquires alarm signals from various communication equipment and communication power supplies, as well as alarm signals such as smoke and switch status in the equipment room. 1.2.2 Remote Control Function a. Remote control operations are performed on communication circuits, in-station communication equipment, auxiliary equipment such as fans, air conditioners, and main and backup power supplies, the main and backup channels of the monitoring system, the monitoring equipment itself, and the start and stop of the terminal station image monitoring system. Examples include remotely controlling the switching of the 800 Hz carrier signal and simulating off-hook operation. b. Provides a graphical remote control interface, placing remote control quantities from the same terminal station or in the same direction on the same interface for easy and intuitive remote control operation and confirmation of multiple quantities. 1.2.3 Intelligent Device Access Function a. Capable of accessing intelligent devices with known communication protocols and built-in external access interfaces (such as microwave, fiber optic equipment, PCM terminal equipment, etc.). b. For intelligent devices that do not provide a communication protocol but have terminal access functionality, they can be accessed as terminals. c. For intelligent devices without a monitoring system, direct acquisition is used for access. 1.2.4 Alarm Processing Function Prioritizes and processes the status and analog quantities of monitored devices in real time, monitors alarm data for system faults, and issues audible, visual, and graphical alarms in real time according to the priority of the alarm level. 1.2.5 Management Function a. Based on the real-time monitoring data and network topology obtained by the system, automatically determines the circuit fault section, cause, or probability of fault, and provides this information to the communication dispatcher. b. Provides an environment and means for drawing various circuit system diagrams, establishes a communication resource management library (such as fiber optic, microwave line resources, carrier channel spectrum resources, etc.), a communication equipment archive database, etc., to effectively manage equipment and provide management technicians with the conditions to compile various circuit management forms. 1.2.6 Display and Printing Functions a. It should have the ability to display various graphs, tables, and data on screen (such as geographical distribution maps, network diagrams, computer room equipment, equipment parameters, system configuration, event displays, system status, curves, trend charts, etc.). b. It should have the function of timed and random printing of various reports (such as daily reports, monthly reports, annual reports, etc.). c. It should randomly print various anomalies, alarms, operation records, etc. 1.2.7 Software Functions a. The software should have an automatic recovery function, data security protection measures, and dual backup of the static database. b. It should have complete interface generation tools and report generation tools. c. It should have the ability to upgrade online. 1.2.8 Data Transmission Functions a. It should be able to exchange data with upper and lower level monitoring systems. b. It should be able to communicate with other management networks and various RTUs. 2. System Design Principles a. The power system communication network monitoring system should comply with the "Technical Specifications for Power Communication Network Monitoring Systems," the "Data Acquisition Layer Transmission Protocol for Power Communication Network Monitoring Systems," the "Computer Data Communication Application Layer Protocol for Power Communication Network Monitoring Systems," and relevant international and national standards. b. The design of the integrated monitoring system should be based on the current status and planning of the communication network to avoid redundant investment and waste. c. When selecting equipment, the advanced technology should be considered as much as possible to meet the needs of system development. d. The system software should consider its versatility and upgradeability. e. To improve system reliability, important components of the system should be hot-backed up (such as front-end servers, servers, etc.). See Figure 3 for a system schematic diagram. [img=350,175]http://zszl.cepee.com/cepee_kjlw_pic/files/wx/hbdljs/2002-1/23-1.jpg[/img][img=320,301]http://zszl.cepee.com/cepee_kjlw_pic/files/wx/hbdljs/2002-1/23-2.jpg[/img] 3. System Application Currently, communication stations in 220 kV and below substations in various regions of the southern Hebei power grid are basically no longer staffed. How to solve the problem of remote maintenance and management of communication equipment, ensure the normal operation of the system, and transform the system from local management to network-wide management, and from manual monitoring to automatic monitoring, has become an important part of the current communication network construction. A regional-level integrated monitoring system for power communication networks should be built as soon as possible, with the central station located at the local dispatch center. The system is configured with front-end processors, servers, modems, workstations, etc., with dual-machine hot backup for the front-end processors and servers. Substations are located in the communication equipment room of the substation. It is also equipped with RTUs, PCs, modems, etc., to achieve remote monitoring and management of power line carrier equipment, microwave equipment, optical transmission equipment, PCM terminal equipment, power supplies, air conditioning equipment, and the equipment room environment. Monitoring information required by various communication devices is accessed through different airborne units or protocol converters to achieve the monitoring functions described in Section 1.2. The above system configuration can be gradually expanded as more communication stations are added, and the configuration of ports within the stations can be adjusted according to the type and number of communication devices within the stations.