Rural Power Grid Research Articles

Modeling load distribution for rural photovoltaic grid areas using image recognition

Expanding photovoltaic (PV) resources in rural-grid areas is an essential means to augment the share of solar energy in the energy landscape, aligning with the “carbon peaking and carbon neutrality” objectives. However, rural power grids often lack digitalization; thus, the load distribution within these areas is not fully known. This hinders the calculation of the available PV capacity and deduction of node voltages. This study proposes a load-distribution modeling approach based on remote-sensing image recognition in pursuit of a scientific framework for developing distributed PV resources in rural grid areas. First, houses in remote-sensing images are accurately recognized using deep-learning techniques based on the YOLOv5 model. The distribution of the houses is then used to estimate the load distribution in the grid area. Next, equally spaced and clustered distribution models are used to adaptively determine the location of the nodes and load power in the distribution lines. Finally, by calculating the connectivity matrix of the nodes, a minimum spanning tree is extracted, the topology of the network is constructed, and the node parameters of the load-distribution model are calculated. The proposed scheme is implemented in a software package and its efficacy is demonstrated by analyzing typical remote-sensing images of rural grid areas. The results underscore the ability of the proposed approach to effectively discern the distribution-line structure and compute the node parameters, thereby offering vital support for determining PV access capability.

Performance Optimization Design Study of Box-Type Substations Subjected to the Combined Effects of Wind, Snow, and Seismic Loads

As a pivotal node in both urban and rural power grids, the box-type substation not only serves the functions of power conversion and distribution but also need to provide structural support and environmental adaptability. However, deficiencies in strength, stiffness, or vibration characteristics may lead to vibration and noise issues, and extreme environmental changes can pose risks of structural damage. This study aims to verify and optimize the seismic resistance and environmental adaptability of box-type substations through finite element simulation methods. Using SOLIDWORKS, a three-dimensional model of the box-type substation was constructed, and static and dynamic analyses were conducted using Ansys Workbench to comprehensively evaluate the dynamic response of the box-type substation under wind, snow loads, and seismic action. Through iterative simulations and a comparison of multiple design solutions, the structural optimization of the substation was achieved. The optimized structure balances strength and stiffness, significantly reducing the weight of the substation body, with the wall thickness reduced by 60%. Additionally, the phenomenon of stress concentration on the side walls was eliminated, ensuring that the equivalent stress is below the material yield strength. This research provides methods and empirical results for enhancing the performance and reliability of box-type substations under seismic conditions, confirming the feasibility of a lightweight design, while ensuring structural safety.

Analysis on the development of modern rural power grids with low carbon serving rural revitalization from the perspective of scientific and technological innovation

Abstract Our country is a large agricultural nation where the development of rural areas holds paramount importance. To achieve rural revitalization, the development of electric power infrastructure is crucial. However, to ensure sustainable growth, attention must be directed towards low-carbon initiatives. With the continuous advancement of science and technology, rural power grids are steadily transitioning towards intelligent development, marking a significant stride in our nation’s power grid evolution. The establishment of smart grids can effectively address energy consumption issues in rural areas, simultaneously aiding in the reduction of energy usage and carbon emissions. Information technology, interactivity and automation are pivotal technical features characterizing the intelligence of rural power grids, leveraging technological advancements to drive the reform of modern rural power systems. This article intends to focus on optimizing low-carbon development within the ambit of intelligent rural power grid construction, alongside a comprehensive analysis of related developments. Such efforts aim to seamlessly integrate rural power development with a low-carbon economy, offering crucial insights and guidance for the sustainable growth of rural power grids. This endeavor contributes to the overarching objectives of rural revitalization and fostering a low-carbon economy.

Development path of a modern rural power grid under dual carbon target based on data analysis

Abstract In China’s economic and social development planning, dual carbon goals and modern rural constructions have become new keywords. It is important to realize the green transformation of energy systems and complete the construction of a modern rural power grid based on data analysis under the guidance of dual carbon goals. Based on the systematic summary of the rural energy structure, this paper assesses the current situation of the scientific and technological development of rural power grids, analyzes the main problems faced by the development of rural power grids, and gives suggestions on the path of energy transformation and the path of rural power grid development. The results show that rural energy transformation plays an important role in the implementation of the dual carbon goals, and the relationship between the long-term and short-term goals of rural energy transformation, top-level design and differentiated development, government regulation and market forces, development stage and energy consumption expenditure must be handled well. In addition, as an important support, rural power grid enterprises should seize the opportunities brought by the construction of rural power grids under the dual carbon goals, make rural power a technology to be valued, and promote the further development of new energy-related technologies.

СОВЕРШЕНСТВОВАНИЕ ЦЕН НА ОПЛАТУ ПОТРЕБЛЕННЫХ ЭНЕРГОРЕСУРСОВ В ЖИВОТНОВОДСТВЕ

At large scale dairy producing enterprises, having an innovative technical-and-technological resource in livestock there is an expanded type of reproducing. At the same time, scientific-and-technological progress in the technical-and-technological production’s improvement in animal breeding, feeding and other areas of dairy cattle management, ensuring a products’ unit in labor intensity and cost reducing is being achieved. Despite the Russian Federation Government’s measures by the agriculture development, dairy cattle breeding have continued a tendency to the number of cows is facilitated by a long industry production cycle reducing, as well as weak material-and-technical base and dairy farms and complexes’ an inadequate energy system supplying. As a result, the milk production sustainability in the regions is low. The methodology of the industry’s power supply systems technical-and-economic assessment in the context of accelerating technical-and-technological reequipment and livestock’s reliable and high quality energy supply to importance is presented. The effectiveness of electrification of technological processes’ technical means for the industry products’ producing using largely depends on the quality of power supplying. In addition the electricity supply reliability, it is necessary the energy supply system efficiency by the electricity’s supply quality parameters influence taking into account the level of economic losses from insufficient reliability of rural power grids increasing. A calculating method for economic feasibility of local energy supply systems using in livestock has been proposed, that has been tested in the divisions of a large, closed cycle meat and dairy products "from field to counter", agroholding "Agropromkomplektatsiya" producing. The results confirming the economic feasibility of local energy supply systems for large scale production using study and of livestock products processing. The energy production by the energy complex cost turned out to be almost in 40% lower than the electricity tariff and more than in 20% lesser than the thermal energy tariff establishing.

АНАЛИЗ КОНФИГУРАЦИИ СЕЛЬСКИХ ЭЛЕКТРИЧЕСКИХ СЕТЕЙ 10 КВ

Currently, the works of domestic and foreign scientists explore options for improving medium-voltage electrical grids by introducing distributed automation tools. However, statistical data on the configuration of existing rural power grids of 10 kilovolts are not sufficiently presented in the literature. (Research Purpose) The research purpose is analyzing the configuration of rural electrical grids of 10 kilovolts, taking into account the transformer substations connected to them and the types of wires used. (Materials and methods) The analysis of 165 supporting schemes of 10 kilovolt overhead power transmission lines of one of the electric grid companies was carried out. (Results and discussion) It is found out that the arithmetic mean of the length of the overhead line of 10 kilovolts to the most remote point of the grid is 9.2 kilometers, and the total length is 13.2 kilometers. It is found that that the specific power per kilometer of the rural grid of 10 kilovolts is 82 kilovolt amperes per kilometer. At the same time, an average of 5 taps are from one 10-kilovolt line, and the average length of the them is 0.68 kilometers. It was also revealed that 72 percent of the total length of the analyzed power transmission lines of 10 kilovolts does not meet the requirements for mechanical strength under icy and wind loads. (Conclusions) The analysis reflects the current configuration of rural 10 kV power grids in the Orel region, while 10 kV overhead lines in other regions may have their own characteristics.

АНАЛИЗ ПЛАНОВЫХ И АВАРИЙНЫХ ОТКЛЮЧЕНИЙ В СЕЛЬСКИХ ЭЛЕКТРИЧЕСКИХ СЕТЯХ 0,4 КВ

Interruptions in the power supply of rural consumers are associated with emergency and planned outages. Using the example of one of the central regions of Russia, an analysis of statistical data on accidents and planned outages in rural power grids of 0.4 kilovolts for the period 2018-2023 was carried out. (Research Purpose) The research purpose is analyzing statistical data on emergency and planned outages in rural power grids of 0.4 kilovolts and identifying the relationships of these types of outages. (Materials and methods) Used literature sources, collected statistical data on the number of emergency and planned outages. Their analysis was performed by descriptive and diagnostic methods. (Results and discussion) It was shown during the descriptive analysis that there is an increase in outages of all kinds with a peak in 2023. It was determined during the diagnostic analysis that this is due not only to physical and moral wear and tear of the equipment, but also to changes in the accounting procedure for emergency shutdowns adopted in 2021. We have identified a significant impact on the number of outages of the self-isolation period due to COVID-19, as in 2020 the number of planned repairs decreased by 38 percent compared to 2019. It was found that due to a decrease in the number of scheduled repairs, there was an increase in emergency shutdowns in 2022 - by 1.5 times, in 2023 - by 5.7 times. (Conclusions) A correlation analysis was carried out by the number, duration of emergency and planned outages and the total power turned off by types of outages. It was stated that the correlation for all the studied indicators for the period 2021-2023 has become higher compared to the period 2018-2021, as the system for recording outages after the changes in 2021 turned out to be more objective. It was noted that the number of planned and emergency outages has a linear correlation of at least 0.83 for the entire study period.

ОЦЕНКА ВЕРОЯТНОСТИ НЕСАНКЦИОНИРОВАННОЙ ПОДАЧИ НАПРЯЖЕНИЯ В СЕЛЬСКИХ ЭЛЕКТРИЧЕСКИХ СЕТЯХ 0,4-10 КВ

One of the causes of electrical injuries in rural power grids of 0.4-10 kilovolts is the unauthorized power supply, which is caused by various causes: the fall of a wire from one power line to another (disconnected), incorrect connection of an electric generator in a private household, etc. At the same time, the occurrence of a power supply in the 0.4 kilovolt grid due to reverse transformation at the 10/0.4 kilovolt transformer substation leads to the appearance of a voltage in the 10 kilovolt grid and poses a danger of electric shock both in 0.4 and 10 kilovolt grid. However, it is not possible to identify the number of cases of unauthorized power supply based on statistics or other data due to the fact that this information is not recorded until the accident occurs. Therefore, the definition of cases of unauthorized voltage supply is actual. (Research Purpose) The research purpose is estimating the probability of unauthorized power supply in electrical grids of 0.4-10 kilovolts. (Materials and methods) Methods of expert survey and processing of its results were applied. 74 experts serving rural power grids of 0.4-10 kilovolts were interviewed, who were asked questions about actual cases of unauthorized power supply and the expectation of meeting with such cases. Based on the results of the survey, the specific probabilities of the unauthorized power supply per kilometer of the line were determined (Results and discussion) The actual number of cases of unauthorized power supply recorded by experts has been determined, which amounted to 91 cases over five years, and the specific value is 0.011 cases per kilometer of lines per year. The assessment was carried out taking into account the total length of the grid serviced by experts - 1704 kilometers. The specific value of the probability of unauthorized power supply was determined according to experts (0.0056 cases per kilometer of lines per year). (Conclusions) The number of cases of unauthorized power supply predicted by experts is lower than the actual one, which confirms the need for additional training of personnel of power grid organizations on this issue.

Study on the Development of Distributed Energy in Northern China of Rural Energy Transformation

Distributed energy is a crucial breakthrough and focus for the green and low-carbon transformation of rural energy in China. It has experienced rapid development in recent years. However, mismatches between rural energy production and consumption capacities, and between the unregulated construction of distributed energy systems and the capacity of rural power grids, have become increasingly severe. These issues are hindering the establishment of a new energy system and the modernization of rural areas. This paper addresses the problems and challenges faced in the development of rural energy in China. Through an investigation and analysis of the experiences and shortcomings in the development and utilization of distributed energy in Northern China, the paper proposes measures and suggestions to promote the scientific development of distributed energy in rural China.

Analysis of Technical Problems and Construction Safety Measures of Rural Power Grid Engineering

In recent years, the state attaches great importance to the construction and improvement of the rural power grid, and the implementation of a series of power grid engineering transformation and new projects, such as a new round of rural power grid transformation project has effectively improved the power supply capacity of the rural power grid, for the agricultural development of rural areas to provide a solid and powerful power grid foundation. This paper probes into its technical problems and construction safety.

Study on the Change of Power Consumption Structure in Xumai Township, Nimu County, Lhasa, Xizang

The research on the evolution of rural power consumption structure in Xizang reflects the information on rural power development in Xizang, and the information on rural power development shows the people's living standards and demand trends. In order to understand the depth of changes in the power consumption structure of farmers and herdsmen households, the project team conducted a field survey of the changes in power supply sources, power consumption structure, power consumption equipment, and operation and management status of Sumai Township, a typical village in Nimu County, Lhasa City, Xizang over the years, and explored the history and trend of power development in remote villages in Xizang. Field research has found that before 2014, the township mainly relied on small-scale independent solar photovoltaic power supply, which was almost used for lighting; Since the implementation of the State Grid in 2014, electricity consumption has shifted from low voltage to wide voltage. In the past three years, the annual electricity consumption growth rate in Xumai Township has exceeded 6%, and the power supply stability has reached 90%. At the same time, the township utilizes solar photovoltaic street lights. The electrical appliances used have developed from a single lamp to power appliances such as household appliances, agricultural electric vehicles, tsamba machines and oil presses. The distribution line of the township is gradually being replaced with medium and low voltage, and is equipped with a 35kV Xumai substation. The 10kV medium and low voltage distribution network project of the rural power grid is gradually being put into operation and put into practice. However, research has found that villagers hope to use more clean energy such as solar energy for power supply and heating, in order to reduce the cost of electricity and gas bills.

Research on rural power grid planning method based on improved genetic annealing algorithm

Current power grid planning mainly relies on planning experience in personnel selection schemes. Planning results of subjectivity are stronger, making the planning after the network loss difficult to meet the requirements. According to the above defects, research on rural power grid planning methods based on an improved genetic annealing algorithm is proposed. Using the directed graph, the operation mode of the rural power grid is analyzed, and the network load of different distributed power sources is calculated. The multi-objective programming model is established from two aspects of the economy and environmental protection of the rural power grid. The annealing algorithm is introduced in the crossover and mutation stage of the genetic algorithm. In the example experiment, the cost reduction of the improved genetic annealing algorithm is 57.45%, and the network loss rate is lower than that of the other planning methods, which makes the network power supply more reliable.

The Application of Photovoltaic-Electric Spring Technology to Rural Power Grids

Rural power grids are essential for rural development, impacting the lives of farmers, the agricultural economy, and the overall efficiency of agricultural production. To ensure the reliable operation of these grids, finding ways to provide high-quality power is imperative. In recent years, the penetration rate of distributed photovoltaic (PV) in the distribution network has been increasing. When the output of PV and load are not matched, the voltage fluctuation of the network affects the safe and stable operation of the distribution network. In this study, we propose that the stable operation of rural power grids can be achieved by employing a photovoltaic-electric spring (PV-ES) device. A state space model of PV-ES is established and a single PV-ES voltage control method, based on a PI controller, is proposed, taking a rural user household with a monthly power consumption of about 120 access to distributed power supply as an example. We analyzed the device’s effectiveness in addressing voltage fluctuation issues as well as how light intensity impacts its effectiveness. The implementation of the PV-ES device solves the most significant problem faced by rural power grids, namely, the unstable power supply that occurs during peak electricity consumption periods. In addition, the PV-ES device ensures a high-quality electricity consumption experience for consumers.

Assessment method of large-scale distributed power consumption capacity for rural grids

As the scale of photovoltaic (PV) access continues to expand, both transmission and distribution grids are experiencing systemic consumption problems, with rural distribution grids being particularly prominent. An accurate assessment of distributed power consumption capacity is crucial to the improvement of distributed power consumption capacity. Firstly, taking into account the uncertainty of the output of the distributed power supply and comprehensive consideration of power quality, reliability of the electricity supply and operational influences, A comprehensive index evaluation system has been established to assess the ability of distributed power sources to consume; secondly, hierarchical analysis and improved gray correlation analysis are used to assign weights to the indexes; finally, a Monte Carlo model is used to identify the consumption capacity of rural power grids. This method can provide a comprehensive and accurate assessment of the consumption capacity of large-scale distributed power sources in new rural power grids, and also provide data support for solving the problem of new energy consumption in power grids.

Research on application of power Internet of Things technology in leakage fault diagnosis of rural power grid

The accuracy and efficiency of current leakage fault diagnosis methods in rural areas are low. In view of this defect, a rural power leakage diagnosis system based on narrowband Internet of Things is studied and designed. Aiming at the defect that the magnetic modulation sensor with single magnetic core structure is prone to zero drift and temperature drift, which increases the measurement error, a magnetic modulation sensor with double magnetic core structure is proposed. Aiming at the problem that the output voltage waveform of the sensor in the square wave excitation scheme is not ideal and the calculation is complex, a half-wave excitation scheme is proposed to make the output voltage waveform of the sensor more ideal and reduce the calculation complexity. The experimental results show that the diagnostic accuracy of the leakage diagnosis system of rural power grid designed according to the research has reached 95%. To sum up, the rural power grid leakage diagnosis system can effectively improve the diagnosis accuracy of power grid leakage, and provide guarantee for rural people’s livelihood and economic development.

A brief discussion on the problems and suggestions of post-supply management in China

With the rapid development of China's social economy, the problem of post-supply management of public goods has become increasingly prominent. This paper takes the rural power supply system as an example to make an in-depth study of post-supply management. In recent years, the rapid development of rural areas has put forward higher requirements for the supply and management of rural power grid. Therefore, we must pay more attention to rural power grid transformation, and timely respond to farmers' demand for rural power grid to meet the needs of rural development in the new era. This paper firstly clarifies the concept of post-supply management, then analyzes the formation background and performance of this problem in practice, and finally analyzes the problems existing in the process of rural grid transformation in detail, and puts forward the framework of the feasibility scheme.

Peak Load Shifting Control for a Rural Home Hotel Cluster Based on Power Load Characteristic Analysis

The large-scale rural home hotel clusters have brought huge pressure to the rural power grid. However, the load of rural home hotels not only has the inherent characteristics of rural residential buildings but is also greatly impacted by the occupancy rate, which is very different from conventional buildings. Therefore, the existing peak shifting strategies are difficult to apply to rural home hotels. In view of the above problems, this study took a typical visitor village in Zhejiang Province as the research object, which had more than 470 rural home hotels. First, through a basic information survey and power load data collection, the characteristics of its power load for heating, cooling and transition months were studied, and a “No Visitors Day” model was proposed, which was split to obtain the seasonal load curve for air conditioning. Then, combined with the characteristics of the air conditioning power load and the natural conditions of the rural house, a cluster control peak-load-shifting system using phase change energy storage was proposed, and the system control logic was determined and established. Finally, the collected power load data was brought into the model for actual case analysis to verify its feasibility and the effect of peak-load shifting. The results showed that due to the influence of the number of tourists, the electricity loads on weekends and holidays were higher, especially the electricity load of air conditioning equipment in the heating and cooling seasons. An actual case was simulated to verify the peak-shifting effect of the proposed regulation strategy; it was found that the maximum peak load of the cluster was reduced by 61.6%, and the peak–valley difference was 28.6% of that before peak shifting.

Application of Low Voltage Treatment Device Based on Electrochemical Energy Storage

With the rapid development of social economy, the power supply capacity of the existing power grid has been far from the increasing load demand, especially the summer (winter) peak period. The problems such as heavy overload of power grid equipment and low voltage of line are extremely prominent and seriously affects the safe and stable operation of the power grid. This problem is more serious in the rural power grid. In order to increase the progress, shorten the construction cost of upgrading and transformation of the traditional power grid, a technical scheme is proposed in this paper by using electrochemical energy storage technology to solve the overload and low voltage problems of local power grid equipment, and obvious results have been achieved through pilot project.

Study on Comprehensive Efficiency Evaluation of Rural Power Grid under Rural Revitalization Strategy Considering Regional Differences

Study on Comprehensive Efficiency Evaluation of Rural Power Grid under Rural Revitalization Strategy Considering Regional Differences

A novel forecast scenario-based robust energy management method for integrated rural energy systems with greenhouses

Traditional energy supplies in rural areas are mainly rural power grids and fossil energy, which makes energy use inefficient and is not environmentally unfriendly. With the development of agricultural intelligence and the increasing seriousness of environmental problems, rural areas urgently need to make full use of the rich local renewable resources such as biogas and wind power. Meanwhile, it is also necessary to jointly optimize the supply of electricity and heat energy to improve energy utilization efficiency and reduce emissions. In this paper, a cooperative operation framework of the integrated rural energy system with greenhouses (IRES-GH) is introduced and a novel forecast scenario-based robust energy management method is presented to hedge the uncertainty of electric load and wind power output. Based on the forecast bounds of uncertain variables, a two-stage robust optimization (TSRO) model of the IRES-GH is first built. Using the TSRO model, the operation status of the units and energy storage elements in the worst-case scenario can be got. Then, the deterministic dispatch model is constructed based on the obtained operation status of devices and the day-ahead hourly point forecast scenario of uncertain variables to enhance the economy of the dispatch results. Since the second stage of the TSRO model includes binary variables, the nested column and constraint generation (NC&CG) algorithm is used to solve it. The effectiveness of the model and solution method is verified by two cases with different scales.