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This repository contains postprocessed results that are part of the paper "Identification of reliable locations for wind power generation through a global analysis of wind droughts" published in Communications Earth & Environment. The results are provided on a latitude-longitude grid, except where specified, and include: mean wind speed, annual mean wind speed, mean wind power density, annual mean wind power density, minumum annual mean wind power density, energy deficits for seasonal variability, energy deficits for weather variability, energy deficits for wind droughts, wind speed time series at Lat 53.00 Lon 3.00. Code and instructions required to reproduce these results are available in the GitHub repository at https://github.com/eantonini/Global_wind_droughts.

Load modeling plays an important role in transmission planning studies to anticipate the response of a power system following fault. The composite load model is the latest and the state-of-the-art load model available for transmission planning studies. Many utilities in the US are already using the composite load model or transitioning to use the composite load model for their transmission planning studies. However, the usage of any aggregated load model can in some cases lead to unanticipated and suspect simulation results during certain grid conditions. This paper briefly introduces the composite load model and presents two scenarios where an informed sensitivity study can help transmission planners gain deeper insights into otherwise ambiguous results obtained while using the composite load model during simulations.

With the deterioration of the environment and the difference of peak and valley of the power grid, the promotion of the technology of electric energy storage and energy storage becomes a trend. Removing the policies those have little influence on the promotion of the electric heat storage technology by reliability analysis and calculating the weights of each policy factor on electric heat storage technology promotion by analytic hierarchy process (AHP), providing the government a reference in policy-making. At the same time, we analyze the current situation of electric heat storage technology popularization in China, find out the existing problems in the promotion of the electric heat storage technology. Moreover, by analyzing its main body and its behavior of the electric heat storage technology using some evolutionary game theory models, we find out that different policy ought to be carried out corresponding to different subject. Integrating the emphasis of the electric heat storage technology promotion policy, the current situation analysis and behavior analysis of different subjects, we make some suggestions as reference for the promotion policies of alternative technology of the electric heat storage type electric energy.

With the development of power electronic technology, flexible AC transmission systems (FACTS), such as thyristor controlled series capacitor (TCSC) are widely used. Not only enhancing the control capacity of the system, but also increasing the complexity of the power grid control. At the same time the completed UHV AC/DC hybrid power grid puts forward new requirements for power grid operation and control. In this paper, based on the extended equal-area criterion (EEAC) introduced system of the first swing and reverse swing instability mechanism. Aimed at the access of TCSC to power grid, the problem of lacking of existing security control methods in some system failures that may worsen the problem of unstable modes is furtherly studied. It is noted that the access of TCSC may have negative effects on the security and stability of the power grid. The effects of TCSC will have on the system security and the traditional emergency control are analyzed by the actual power grid data, as well as the corresponding solutions.

Audible noise of can-type filter capacitors in high- voltage direct current converter stations originates from the vibration of capacitor cases, so it is meaningful to investigate the vibration characteristics. However, no experiment under practical excitations or thorough theoretical analysis was presented for the vibration characteristics. This study theoretically and experimentally investigated the vibration characteristics of can-type filter capacitors with stacked elements parallel to bottom. The vibration amplitude was found to be proportional to voltage squared. If the frequency spectrum of excitation voltage included several harmonics (more than three), vibration amplitude on some specific frequencies was related with the phases of these voltage components. Each capacitor surface had a concavo-convex vibration shape and the vibration of the bottom surface and the side surfaces were in opposite phases. The vibration amplitude of the bottom surface was the largest. Moreover, frequency characteristics of capacitor vibration were studied. The frequency response of the bottom surface was bigger than that of narrow and broad side surfaces for lower frequencies, while was smaller for higher frequencies. It was inferred that bottom surface vibration was mainly caused by elastic forces from direct contact and side surfaces vibration mainly came from damping forces from dielectric liquids.

Large-scale integration of wind power generators into power grid brings severe challenges to power system economic dispatch due to its stochastic volatility. Unit commitment including wind farm is analyzed from the two parts of modeling and solving methods. The structures and characteristics can be summarized after classification has been done according to different objective function and constraints. Finally, the issues to be solved and possible directions of research and development in the future are discussed, which can adapt to the requirements of the electricity market, energy-saving power generation dispatching and smart grid, even providing reference for research and practice of researchers and workers in this field.

The defects of the present fault chain model of power grid cascading failures have been summarized and a defined method for forecasting cascading failures is presented based on a fault chain model and Fuzzy C-Means. First, in order to reduce the workload and overcome the limitation of present means, this method selects a number of lines with the high value of predictive index to be the next outage lines during fault chain forecasting. Then, this paper analyzes the correlations among lines. Finally, taking IEEE 39-bus system as example, the rationality of the method proposed is verified based on comparison with other means.

This paper proposes a novel algorithm based on the identification of the most influential lines to speed up the simulation of severe cascading failures in power systems. To this end, we first extend the concept of interaction graph to take into account the impact of hidden failures. Then we devise a PageRank-based algorithm to assess the influence of individual lines, which remarkably facilitates finding such severe cascading failures. Numerical experiments carried out on the New England system show that our algorithm can enhance the efficiency of finding severe blackouts of 1∼2 orders of magnitude.

Market demands on the product performance and additional service of oil-immersed distribution transformer have become increasingly diversified. Single form of oil-immersed distribution transformer product and pure business relationship cannot adapt to current needs. Product service system innovation design can change single product form to the combination of product and service, it has the significance of further satisfying user requirements, and it is an extension service in a new form of physical product. In this paper, according to Kano model, user requirements were collected and classified. Then based on analytic hierarchy process (AHP), each class of user requirements was sorted by optimal weight and recombined. Finally, user requirements were mapped into correlative function/service characteristics, innovation design of oil-immersed distribution transformer product service system was achieved. The results have a certain guiding role for transformer manufacturers to adapt to the demands of power supply enterprises.

Partial discharges (PD) detection for power equipments mainly includes the pulse current method, transient earth voltage (TEV) method, ultrasonic detection method, ultra-high-frequency (UHF) method, and optical detection method. Among them, those PD detection methods realized based on optical fiber sensing technologies has the advantages of safety, insulation and anti-electromagnetic interference. So they are suitable to be designed as embedded or intrusive sensors installed into the power equipments of PD on-line monitoring or live detection with prospects for development. In this paper, the measurement methods of PD ultrasonic signals based on optical fiber sensing technologies, principle parameters and advantages and disadvantages are summarized. At last, the optical fiber sensing technology using extrinsic Fabry-Perot Interferometers (EFPI) is pointed out that it has good application prospect due to its high sensitivity and stability.