The following paper answers your question from the side, hoping to help you. This paper discusses the necessity of low and medium voltage distribution network automation and its PLC implementation scheme, and discusses the necessity of low and medium voltage distribution network automation from the requirements of modern society, the development needs of power enterprises themselves and the development status of distribution network automation at home and abroad. This paper compares several existing distribution network automation schemes, puts forward a solution to realize the automation of medium and low voltage distribution network with programmable controller (PLC), and introduces the concrete realization of PLC scheme in detail. Keywords: distribution network; Automation; With the development of science and technology, it has become the development trend of power system to realize the automation of medium and low voltage distribution network. As the last link of transmission and distribution system, the automation degree of medium and low voltage distribution network is closely related to the quality and reliability of power supply and demand. Therefore, this paper briefly discusses the necessity and realization scheme of automation of medium and low voltage distribution network. 1 Necessity of realizing the automation of low and medium voltage distribution network 1. 1 Realizing the automation of low and medium voltage distribution network is the need of improving people's quality of life and developing national economy. In modern society, the quality of power supply not only reflects the quality of life, level and investment environment of people in a country or region, but also is an important factor affecting economic development and determines the direction and scale of industrial development. In fact, with the advent of the information age, more and more computer equipment requires uninterrupted power supply, which puts forward higher requirements for power supply. Power failure or power limitation will lead to reduced production, while sudden power failure will endanger the important equipment of the factory. Only by realizing the automation of medium and low voltage distribution network can we improve the quality of power supply to the maximum extent and meet the needs of people's daily life, work and production. For details, please visit: transmission and distribution equipment network 1.2. Realizing the automation of medium and low voltage distribution network is the need of power enterprises' own development, which can improve the quality and reliability of power supply. Realizing the automation of medium and low voltage distribution network can reduce the number of faults, narrow the scope of accidents, shorten the time of accidents, and provide effective basis for restoring power supply, quickly analyzing, diagnosing and reporting the causes of accidents. Realizing the automation of medium and low voltage distribution network can improve the economic benefits of the whole power system: reducing the labor intensity of maintenance personnel; Reduce the number of operators; Enhance the maintenance-free nature of power system; It is beneficial to improve the safety and health level of equipment and prolong the service life. Realizing the automation of medium and low voltage distribution network can improve the management level of the whole power grid. It mainly includes: providing more detailed and rich data and information for computer management of power system automatically, accurately and timely, and planning power outage and power supply for any user; It can conveniently and intuitively monitor the electricity consumption and power supply of all users around the world and realize overall control. 1.3 medium and low voltage distribution network is the weak link of distribution network automation in China. Although it started late in China, after nearly 20 years of research and practice, it has achieved initial results. However, most of the research and practice results are carried out at the level of high voltage distribution network (above 35kV), while the automation of medium and low voltage distribution network (at the level of distribution room) is still blank, with neither overall planning nor unified technical principles. Moreover, the current vertical monitoring is generally limited to the monitoring from the substation feeder to the end users before the substation goes out, and there is no other monitoring means except the load control of a few large users. Source of information: 2. Automation scheme of medium and low voltage distribution network 2. 1 Comparison of existing schemes of power system automation. The automation of medium and low voltage distribution network (mainly switch station, switch room and switch station) is similar to that of substation. Therefore, it is of great significance to analyze the realization method of substation automation for correctly determining the automation scheme of medium and low voltage distribution network. Substation automation system consists of five parts: master station, remote terminal unit (RTU), line sensor, remote SF6 or vacuum switch and communication cable. Among them, RTU device is located in the substation site, which can automatically collect various switch state variables (remote signal) and analog signals (telemetry) and transmit them to the monitoring center master station system through special channels; Some RTUs can also perform specific remote control operations according to the intention and instructions of the monitoring personnel, and send the operation results back to the main station system of the monitoring center. Judging from the functions that RTU can realize, substation automation includes three aspects: remote communication, telemetry and remote control. In addition, some systems can also realize the function of electric energy summation according to telemetry results. Accordingly, substation automation systems can be divided into two categories: one is the traditional SCADA system, which only realizes remote communication and telemetry functions; The latest SCADA system belongs to another category and should be able to realize all the "three remote" functions. These two types of systems correspond to different stages and levels of power system automation. From the method of RTU telemetry in substation, RTU has two implementation schemes: and sampling scheme information comes from transmission and distribution equipment network.