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Pumped‐storage hydropower plants can contribute to a better integration of intermittent renewable energy and to balance generation and demand in real time by providing rapid response generation. The utilisation of variable‐speed pump‐turbine units with a doubly fed induction machine is being progressively applied due to its overall efficiency and high level of operating flexibility. This study presents state‐of‐the‐art pumped energy storage system technology and its AC–DC interface topology, modelling, simulation and control analysis. It also provides information on the existing global capacities, technological development, topologies and control strategies of the pumped‐storage system. This report also outlines the analysis of dynamic performances of the system. It also attempts to recommend the future works in this area. This study concludes that pumped storage is the most suitable technology for small autonomous island grids and massive energy storage, where the energy efficiency of pumped storage varies in practice. Around the world, the size of the pumped‐storage plant mostly lies in the range of a small size to 3060 MW. The back‐to‐back voltage source converter topology is mostly conducted due to its significant features. Due to its imperative features, the vector control strategy is widely used. The pumped‐storage plant is dedicated to power management and stability regulation of grid and isolated power systems.

Pumped‐storage hydropower plants can contribute to a better integration of intermittent renewable energy and to balance generation and demand in real time by providing rapid response generation. The utilisation of variable‐speed pump‐turbine units with a doubly fed induction machine is being progressively applied due to its overall efficiency and high level of operating flexibility. This study presents state‐of‐the‐art pumped energy storage system technology and its AC–DC interface topology, modelling, simulation and control analysis. It also provides information on the existing global capacities, technological development, topologies and control strategies of the pumped‐storage system. This report also outlines the analysis of dynamic performances of the system. It also attempts to recommend the future works in this area. This study concludes that pumped storage is the most suitable technology for small autonomous island grids and massive energy storage, where the energy efficiency of pumped storage varies in practice. Around the world, the size of the pumped‐storage plant mostly lies in the range of a small size to 3060 MW. The back‐to‐back voltage source converter topology is mostly conducted due to its significant features. Due to its imperative features, the vector control strategy is widely used. The pumped‐storage plant is dedicated to power management and stability regulation of grid and isolated power systems.

Using the Information–Motivation–Behavioral Skills (IMB) model as a theoretical framework, we examine the direct effects of knowledge, attitude, and subjective norms on young women’s intention toward purchasing green cosmetics, and whether self-efficacy mediates these effects. Data were collected from 433 young female consumers and analyzed using the PROCESS macro for SPSS. Green-cosmetics-related knowledge and motivation (attitude and subjective norms) were positively related to green cosmetics purchase intention. Self-efficacy partially mediated the effects of knowledge, attitude, and subjective norms on purchase intention. The IMB model offers a useful framework for understanding the factors affecting young Vietnamese women’s intention toward purchasing green cosmetics. Marketers promoting green cosmetics should aim to increase consumers’ confidence in comprehending their products.

Using the Information–Motivation–Behavioral Skills (IMB) model as a theoretical framework, we examine the direct effects of knowledge, attitude, and subjective norms on young women’s intention toward purchasing green cosmetics, and whether self-efficacy mediates these effects. Data were collected from 433 young female consumers and analyzed using the PROCESS macro for SPSS. Green-cosmetics-related knowledge and motivation (attitude and subjective norms) were positively related to green cosmetics purchase intention. Self-efficacy partially mediated the effects of knowledge, attitude, and subjective norms on purchase intention. The IMB model offers a useful framework for understanding the factors affecting young Vietnamese women’s intention toward purchasing green cosmetics. Marketers promoting green cosmetics should aim to increase consumers’ confidence in comprehending their products.

This paper proposes a method of load shedding in a microgrid system operated in an Island Mode, which is disconnected with the main power grid and balanced loss of the electrical power. This proposed method calculates the minimum value of the shed power with reference to renewable energy sources such as wind power generator, solar energy and the ability to control the frequency of the generator to restore the frequency to the allowable range and reduce the amount of load that needs to be shed. Computing the load importance factor (LIF) using AHP algorithm supports to determine the order of which load to be shed. The damaged outcome of load shedding, thus, will be noticeably reduced. The experimental results of this proposed method is demonstrated by simulating on IEEE 16-Bus microgrid system with six power sources.

This paper proposes a method of load shedding in a microgrid system operated in an Island Mode, which is disconnected with the main power grid and balanced loss of the electrical power. This proposed method calculates the minimum value of the shed power with reference to renewable energy sources such as wind power generator, solar energy and the ability to control the frequency of the generator to restore the frequency to the allowable range and reduce the amount of load that needs to be shed. Computing the load importance factor (LIF) using AHP algorithm supports to determine the order of which load to be shed. The damaged outcome of load shedding, thus, will be noticeably reduced. The experimental results of this proposed method is demonstrated by simulating on IEEE 16-Bus microgrid system with six power sources.