Country's Power Grid Research Articles

The Construction and application of analytical framework of power grid management system

The power grid management system is an important institutional foundation supporting the development of the electric power industry. The current power grid management system analysis framework with the relationship between transmission and distribution as the core cannot explain the facts well. This paper builds a power grid management system analysis framework composed of "structure layer + factor layer", which can analyze the basic outline of a country's power grid management system and the driving factors behind it in a more comprehensive and systematic way.

Exploring wind curtailment effects and economic implications in the growing variable renewable energy penetration

Several countries continue to invest in variable renewable energy (VRE) sources to replace fossil fuels and achieve a nationally determined contribution. Consequently, as the share of VRE generation in each country's power grid increases, its curtailment also increases. Current studies on VRE curtailment are based on a comparative analysis of statistical data collected from different countries. However, only a few studies present detailed results based on historical curtailment data collected from individual wind farms. This study analyzes the curtailment data collected for three wind farms over four years. The duration, curtailed output, and cost per curtailment were determined to be 200 min, 38 MWh, and $3.02k, respectively. Finally, the curtailment loss to wind farms caused by the increasing share of VRE generation in the power grid was estimated. The curtailed output and curtailment cost are estimated to increase by 1.3 GWh and $107.6k, respectively, when the share of VRE in the power grid increases by 1%. These findings can aid in identifying the curtailment experienced by wind farm operators and subsequent potential economic losses. Moreover, they can form the basis for establishing an efficient curtailment cost compensation system.

Impact of electric vechicles on power transmission grids

This paper presents a methodology for assessing the impact of electric vehicles (EVs) on the power transmission grid of the Costa Rica Power System. The methodology considers penetration scenarios, user preferences, charging habits, and expected fleet growth. Using ETAP software, the study simulates power flow, demand behavior, and voltage levels in the presence of high penetration of electric vehicles. The analysis covers a 15-year horizon and focuses on voltage and demand profiles in 2025, 2030, and 2040. The results indicate a decline in voltage profiles that reaches dangerous levels after 2030, primarily in the distribution grid, and an increase in demand by ▪ for 2040 in the most severe scenario. The analysis also reveals several key findings (a) the identification of problems in the electrical infrastructure starting in 2030 and a major insufficiency in accommodating the increase in EVs by 2040; (b) the need to evaluate stability in transmission grids considering loadability and voltage; (c) the necessity of investing in electrical infrastructure, driven by public policies, to meet future energy requirements and strengthen transmission networks; (d) the significance of accounting for both EV growth and electric infrastructure improvements in system analysis; and (e) the anticipation that the system's performance will fall within the extreme demand values presented in the analysis. The study emphasizes the importance of considering a broader range of scenarios and variability in parameters, especially user charging behaviors, to enable decision-makers to plan for the challenges and opportunities associated with the widespread adoption of EVs in a country's power grid.

Simulation Research on Distribution Characteristics of Electromagnetic Field of AC UHV Transmission Line

With the development of UHV and long-distance power transmission technology in my country's power grid, the electromagnetic environment of 100kV UHV transmission lines will be one of the key issues affecting the feasibility of UHV transmission. The impact of low-frequency noise from UHV AC transmission lines on the lives of residents along the corridor should not be ignored. In particular, pure AC sound attenuates slowly along the line and spreads far away, which often has more serious impacts on the lives of nearby residents. In order to study the distribution law and influence degree of pure sound, this article mainly conducts a more in-depth study on the wiring method of UHV transmission lines through theoretical calculation and computer simulation.

Vehicle-to-grid technology and its suitability for the Moroccan national grid

Thanks to the technological advances in electronic devices and bidirectional power inverters, electric vehicles (EVs) are no longer viewed as just transportation tools. Rather, they could also serve as electric storage units for the grid and supply ancillary services within the framework of vehicle to grid (V2G) technology. Following the successful implementation of this emerging technology in several countries such as Germany and Spain, numerous scientific papers and research activities are addressing the use of V2G via plug-in cable energy transfer or inductive wireless charging. This paper investigates the suitability of such technology for the Moroccan national grid. It outlines the state of art of the V2G technology together with the current status of the country's power grid. Furthermore, the paper takes into consideration the evolution of the EV market in the country as well as the EV charging infrastructure deployed within its territories. Moreover, a survey on the services that the V2G could provide is presented. Finally, the authors conclude that the V2G would be very beneficial for the national power grid, providing up to 7.7 GW of controllable, and mobile loads by 2030, as well as for the EV owners once the recommended incentives are put in place.

Diagnosis and clustering of power transformer winding fault types by cross‐correlation and clustering analysis of FRA results

The power transformer is one of the vital and substantial elements of each country's power grid which not only require high investment, but they are also important in terms of economy, social, political, and strategy. Since this equipment is exposed to different electrical and mechanical winding faults during operation, they should be monitored continuously. One of the main monitoring methods is the use of frequency response analysis (FRA), which has a high sensitivity. The main challenge of the FRA is that the detecting task of the status of the transformer is done by a specialist and with a visual evaluation of the records. To overcome this problem, first, frequency responses in the healthy and present states are calculated through simulation of electrical and mechanical fault in the winding of the transformer and then, new statistical methods are used to interpret FRA results based on the obtained transfer function. In this study, for the first time, clustering analysis and cross-correlation methods are used to interpret FRA results for clustering and diagnosis of different short circuits turns, axial displacement, and radial deformation. Results and simulations verify ability and advantage of these methods in detection and determination of different faults.

Design of Dispatcher Interactive Platform Based-on Text Technology

Recently, voice dispatching telephone is applied as one of information interactive by power grid dispatching in China, playing a significant role in the progress of power grid dispatching. However, with the increasing of grid scale, more and more information should be figured out by dispatchers. Conventional dispatching telephone in communication presents enormous challenge, thus, much effort should be made to solve this problem. In the article, the shortcomings of dispatching telephone in communication are systematically analyzed by the point of our actual country power grid dispatching. To remedy telephones shortcomings, text technology is introduced and a uniform dispatcher interactive platform is formed. This platform meets the requirements of interactive in power grid dispatching perfectly.

Blackouts illuminate India's power problems

For two consecutive days in July, India experienced blackouts that took down large portions of the country's power grid. The second outage was the largest in history, leaving more than 600 million people, nearly a tenth of the world's population, without electricity. The blackouts brought renewed attention to the country's power sector, which is struggling to supply India's growing demand. They exposed weak links in the transmission system, inadequate fail-safe systems for preventing cascading failures, and a lack of proper outage planning.

Comparison of Various Auxiliary Signals for Damping Subsynchronous Oscillations Using TCR-FC

Because of large-capacity, long-distance and cross-region power transmission in our country's power grid, the subsynchronous oscillation (SSO) will arise from the use of series capacitor compensation and HVDC. Damping subsynchronous oscillation using static VAR compensators (SVC) is investigated in this paper.TCR-FC (Thyristor Controlled Rectifier with Fixed Capacitor) is a well known combination to improve voltage stability. Supplementary signals such as variation in reactive power, variation in frequency, variation in active power, variation in current can be used to enhance the dynamic response of the system. Their derivatives also can be used for better performance. In this paper three signals are compared and it is shown that Deviation in Reactive power gives best performance.

Building a North American Spatial Data Infrastructure

ABSTRACT: This paper addresses the state of spatial data infrastructures within North America in late 1997. After providing some background underlying the philosophy and development of the SDI concept, the authors discuss effects of technology, institutions, and standardization that confront the cohesive implementation of a common infrastructure today. The paper concludes with a comparative framework and specific examples of elements and initiatives defining respective spatial data infrastructure initiatives in the United States and Canada. Introduction Over the last three decades, governments and industry in countries around the world have invested tens of billions of dollars in the development of independent land systems designed largely to serve specific communities (forestry, land records management) within a local and regional framework. During the next decade the focus will increasingly shift to the challenges associated with integrating these systems together into--in each case--a national spatial data infrastructure (NSDI). This infrastructure will have the potential to act as an highway which links together environmental, socio-economic, and institutional databases (the horizontal highway) and provides for movement of from the local to national levels and, eventually, to the global community (the vertical highway). Proponents of the infrastructure concept often envision a data infrastructure as being analogous to networks of national highways (Branscomb 1982) or electric power grids in countries around the world. The highway metaphor conveys the notion of new or heightened connections to different locations. Further, as with electric power grids, the physical location of the source is usually less important to the end user than the continuing availability, reliability, and cost of the itself (Anderson 1990). These two metaphors have been widely employed over the past five years in defining and promoting a shared vision of the development of strategic networks and databases. Especially since 1990, a third metaphor--the information marketplace--has attracted the imagination and support of the business community (Coleman and McLaughlin 1998). The proposed development of national spatial data infrastructures has received considerable attention from institutional suppliers, the private sector, and user communities in developed countries around the world. Evolving from earlier data-sharing and program coordination efforts, the term NSDI has come to encompass the sources, systems, network linkages, standards, and institutional issues involved in delivering spatially related from many different sources to the widest possible group of potential users. The development of common frames of reference, technology, and related standards is crucial to the evolution of a data infrastructure that can support interoperability across provinces, states, and countries. This paper outlines the current state of corresponding spatial data infrastructure initiatives in North America and the issues affecting their implementation. From Integrated Mapping to Spatial Data Infrastructure The data-sharing paradigms underpinning the development of geo-spatial networks today are not new. In the 1960s, proponents of integrated mapping practices advocated the registration, overlay, interpretation and analysis of different layers or disparate themes of spatially related data sets to the practical solution of problems in land-use planning and inventory (McHarg 1969). Through the 1970s, the multipurpose cadastre concept launched major topographic and cadastral base-mapping megaprograms to support land administration at the local, state, and federal levels across North America, Australasia, and in emerging nations (McLaughlin 1975). By the early 1980s, the notion of information as a corporate resource (Diebold 1979) emerged, and the resources management movement encouraged individual organizations to implement enterprise approaches to the collection, management, and sharing of designated hard-copy and computer-based data holdings of corporate-wide interest. …