Line loss rate is an important technical and economic index of power grid enterprises. Strengthening line loss management can not only reduce cost and increase efficiency, improve lean management level, but also timely check security risks, optimize distribution network structure, and provide users with more secure and reliable power supply services. In recent years, with the promotion of smart meters and automatic collection, State Grid Co., Ltd. has occupied the three technical difficulties of data specification, grid topology splitting and data abnormal distortion according to the ideas of power source collection, line loss automatic generation and abnormal intelligent monitoring, built a line loss management system in the same period, and finally covered up the "plant station line transformer household" measurement equipment of the whole network. Organic and orderly interconnection has greatly promoted the construction of ubiquitous power Internet of things.
Line loss, big data, relevant sharing, powerful consolidation of ubiquitous power Internet of things construction
Since the founding of new China 70 years ago, China's power industry has been developing rapidly, and its power generation capacity and scale have ranked first in the world. However, with the further promotion of clean and low-carbon power transformation, various new ways of energy use continue to emerge, and the traditional power production and consumption forms in China have not been able to meet the needs of the country's long-term sustainable development. Facing the disordered economic situation, the new strategy of "three types, two networks, and first class in the world" proposed by State Grid Corporation of China is the key action to promote the transformation of power grid to power Internet.
Kou Wei, chairman and Secretary of the Party group of State Grid Corporation of China, stated at the mid year working conference of State Grid Corporation of China: "accelerate the construction of" three types and two networks ", enable the traditional power grid with digital skills, continuously improve the perception ability, interaction level and operation efficiency of the power grid, complete the promotion of the power grid, and boost the power production and consumption revolution."
After the birth of power plant, electric energy enters thousands of households through power grid. In this process, the demand goes through four links: transmission, transformation, distribution and power consumption, and power loss occurs in each link, which is called line loss for short. Line loss rate is the ratio of power loss to power supply in a certain period of time. It is an important technical and economic index of power grid enterprises.
Line loss mainly consists of skill line loss and handling line loss. The technical line loss is the physical loss of the equipment distributed and sold through the transmission transformer. The handling of the line loss is the loss of electric energy caused by metering, meter reading, power stealing and other improper handling. Data shows that every 1% reduction in line loss rate can save SGCC more than 40 billion kwh of power purchase and 15 billion yuan of power purchase cost. How to use digital skills to reduce the line loss rate of each link is a problem that the State Grid has always attached great importance to, and also an important content of ubiquitous power Internet of things construction.
It is not easy to reduce the line loss rate. The relevant person in charge of the development planning department of State Grid Co., Ltd. said: "the line loss involves many substations, transmission lines, distribution lines, distribution transformers, intelligent energy meters, etc., which are related to the development, dispatching, marketing, operation and inspection and other professional parts. Each professional part has its own line loss management system. They are like parallel lines, without intersection. How to integrate these data and carry out relevant analysis, explore the value of data, and find hidden problems, which is the key to reduce the line loss rate, and also the foundation of promoting the construction of ubiquitous power Internet of things. "
It seems that the "development - transmission - Transformation - distribution - use" and other links that strike while the iron is hot have experienced data barriers due to different professional division of labor. Data errors are hard to avoid, which directly affect the operating efficiency of enterprises.
At the same time, the birth of line loss system is just to break through the information barrier between professional parts. It has completed cross professional integration, integration on the whole line, zero manual input, and whole chain penetration. According to the problem-oriented, it has completed layer upon layer penetration and closed-loop management and control. It has built a set of collaborative work form of joint management, which promotes the collaborative integration and friendly interaction of various specialties such as grass-roots development, scheduling, operation inspection, marketing, measurement, etc.
In the process of promoting the line loss system in the same period, it is the foundation of the efficient operation of the system to complete the integration of data of various professional parts. State Grid Chongqing Electric Power Co., Ltd. launched the relevant director of the planning department to introduce: "we use two years to complete the data processing work of each professional part, and complete the relevant analysis of big data. Through the system, all kinds of problems can be seen at a glance. Once we found a line problem when we trained the grass-roots workers how to use the system. The power supply workers immediately went to deal with it, greatly improving the work efficiency. "
In 2016, the line loss system of the same period was comprehensively promoted in the operation area of the State Grid. Through three years of construction, the system completed the full cover up of headquarters, six branches, 27 provincial companies, 221 city companies, 1686 County companies, 21400 power supply stations, and completed the full monitoring of electricity quantity of 40000 substations, 81000 transmission lines, 270000 distribution lines, and 4.34 million distribution voltage transformers of the State Grid. With the daily monitoring of line loss, the topological diagram of "station line transformer box (meter) - Household" of the full voltage level is clear, forming a big data chain of electricity throughout the whole process of "generation transmission transformer distribution consumption", further promoting the penetration of operation and distribution data.
According to the relevant person in charge of the planning department of State Grid Corporation of China, big data is the foundation of building ubiquitous power Internet of things. However, as long as high-quality data that can verify the authenticity of each other is really valuable data, it can improve the perception ability, interaction level and operation efficiency of power grid. The line loss system of the same period first completes the "three flows" of energy flow, information flow and transaction flow in the scope of power management.Accurate diagnosis of abnormal point of line loss
Compared with the previous line loss management system, the line loss management system in the same period has broken through professional barriers such as deployment, dispatching, transportation inspection and marketing in the horizontal direction, and completed the "four points" line loss online calculation, automatic generation and real-time monitoring in the vertical direction in the sub areas, sub voltage, sub lines and sub station areas. It can accurately locate the weak link of high loss, expose the equipment and management in time, and give full play to the line loss rate index. Sensitive monitoring effect of the target.
On February 23, 2018, Xiushan County power supply company of Chongqing used the line loss system of the same period to conduct an abnormal analysis of 10kV lines, and found that Yongguang line suffered high loss for many months. Through investigation, the staff found that the meter of meijiaju property company had more than 50 open records, suspected of stealing electricity. Through the case investigation of the public security organ, it is found that 14 meters related to the user are equipped with electric stealing equipment, resulting in abnormal high loss of 5 10kV lines. According to calculation, since July 2015, the user has stolen more than 4.4 million kwh of electricity and paid less than 3.3 million yuan of electricity fee. The line loss rate of 5 10kV lines in the same period of line loss system decreased significantly after the power stealing users were removed.
State Grid Chongqing electric power company's relevant person in charge said that with the line loss system of the same period, monitoring data will be left where the current passes, and every equipment operation will leave traces. These data can be shared in the system, and problems will be exposed at any time, and users like electricity stealing have nowhere to hide. It is also based on the remarkable effect of this skill that many electricity stealing users are afraid, and Xiushan County has the phenomenon of electricity stealing users queuing up to pay for electricity.
Relying on the massive data mixed by various disciplines, the line loss system of the same period can intelligently calculate the daily and monthly line losses online, strengthen the system data monitoring and analysis of high loss platform area, and take the analysis results of the system as the guide to conduct targeted on-site investigation of abnormal users of electricity, effectively block the flow of electricity, improve anti stealing handling ability, and achieve accurate loss reduction.
The accurate diagnosis of line loss system in the same period has not only been widely used in Chongqing, but also achieved remarkable results in many provinces of the country. On February 10, employees of Liaoning Jinzhou power supply company found a 10kV line with high loss. There are 140 enterprise users on this line. Power supply employees quickly and accurately locate the power stealing enterprise through the formula calculation of data in the system. Relying on the line loss system of the same period, in June, Fujian Sanming power supply company became the first batch in China and the first one in Fujian Province to completely eliminate 10kV line. And Taiwan District loss bearing city company. The occurrence of negative loss is that the power supply is less than the power purchase, which indicates that the power supply enterprise has the problem of inaccurate measurement or handling gap, and the use of line loss system in the same period makes the negative loss problem get useful governance.
With the extensive promotion of the line loss system in the same period, the State Grid has completed the organic and orderly interconnection of the "plant station line transformer household" metering equipment of the whole network, completed the quasi real-time online monitoring of power and line loss information at all levels, specialties and links, occupying the three technical difficulties of data specification divergence, grid topology splitting and data abnormal distortion, and further verified the root. According to the feasibility of integrating and unifying terminals to support multi-disciplinary use, a digital power ecosystem has been built, which is an important practice in the construction of ubiquitous power Internet of things terminals.
Multi professional integration and participation to provide customers with efficient power services
"I didn't expect that before I called for repair, the repair technician came." One day in July, Guo Wei, who lives in jinjixiaolu community, Hangzhou, Zhejiang Province, enjoyed the automatic repair service of power supply workers.
The rush repair master came quickly, thanks to the fast and accurate data. The precise data comes from Hangzhou power supply company's efforts to promote line loss management in the same period, which lays a solid foundation for automatic repair.
This is just a microcosm of line loss system serving customers in the same period. The use of line loss system in the same period is the detailed performance of the Internet of things skills of State Grid Corporation of China, and is an important practice of ubiquitous power Internet of things. Han yingduo, academician of the Chinese Academy of engineering and professor of Tsinghua University, said: "ubiquitous power Internet of things is not an intention, but a technique. It will be useful to deal with the serious problems in the development, transmission, distribution, use, management and service of China's power system, and promote the development of power revolution."
The line loss changes objectively reflect the running through problem of operation and distribution. During the same period, the line loss system has established the enterprise level visual big data use covering the whole voltage level of power grid, handling all levels of State Grid Co., Ltd. and producing all specialties. According to the objective quantitative data, it has constructed a set of multi specialty and cross category cooperative operation forms, which is useful to promote the coordination of development, regulation, operation and inspection, marketing and other specialties. Integration, friendly interaction and joint management lay a solid foundation for meeting the needs of economic and social development.
The professional cooperation and integration has achieved remarkable results. State Grid Beijing electric power company launched the planning department to summarize Wu Honglin from the planning department, who said: "at present, 423 data exchanges of 6 professional systems of State Grid Beijing Electric Power Co., Ltd. are shared, with a daily data exchange volume of 16 million. State Grid Beijing Electric Power Co., Ltd. has established the line loss rate, collection concealment rate, collection success rate, measurement equipment change, file change, model configuration and other line loss chain throughout the analysis, quickly find and handle problems, gradually improve the qualified rate of line loss, summarize the steady decline of line loss rate, and provide customers with more secure and reliable power supply services. "
In recent years, the prevention and control of air pollution has been paid more attention. "Coal to electricity" has become the current prevention and control of air pollution due to its low difficulty and quick effect.
