Experimental Research on Compensation for Power Fluctuation of the Renewable Energy Using the SMES Under the State-of-Current Feedback Control

2015 ◽  
Vol 25 (3) ◽  
pp. 1-5 ◽  
Author(s):  
Daisuke Miyagi ◽  
Ryosuke Sato ◽  
Natsumi Ishida ◽  
Yuuki Sato ◽  
Makoto Tsuda ◽  
...  
2020 ◽  
Vol 1 (2) ◽  
pp. 189-193
Author(s):  
Aisha Naiga ◽  
Loyola Rwabose Karobwa

Over 90% of Uganda's power is generated from renewable sources. Standardised Implementation Agreements and Power Purchase Agreements create a long-term relationship between Generating Companies and the state-owned off-taker guaranteed by Government. The COVID-19 pandemic and measures to curb the spread of the virus have triggered the scrutiny and application of force majeure (FM) clauses in these agreements. This article reviews the FM clauses and considers their relevance. The authors submit that FM clauses are a useful commercial tool for achieving energy justice by ensuring the continuity of the project, despite the dire effects of the pandemic. Proposals are made for practical considerations for a post-COVID-19 future which provides the continued pursuit of policy goals of promoting renewable energy sources and increasing access to clean energy, thus accelerating just energy transitions.


Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3765
Author(s):  
Jarosław Brodny ◽  
Magdalena Tutak ◽  
Peter Bindzár

The global economic development is, to a great extent, dependent on access to large amounts of cheap energy sources. The growing social awareness of ecology and the enormous damage to the Earth’s ecosystem due to the production of energy from conventional sources have forced fundamental changes in the energy sector. Renewable energy is considered to be an opportunity for such changes. The current state of the art allows such changes to be made without restricting economic development. Therefore, activities related to the energy transition are being taken all over the world. The European Union has definitely managed to achieve the most tangible effects in this regard. This article presents the findings of the research aimed at presenting the current state of renewable energy in the European Union and analyzing the changes reported in this sector in the last decade. The research was carried out using a selected set of 11 indicators characterizing renewable energy in individual countries. These indicators were selected on the basis of literature review and own studies of the state of renewable energy and its development prospects. Based on these indicators, changes in the energy structure of individual European Union countries between 2008–2018 were determined. The study is divided into two main stages. The principal components analysis (PCA) was used for the first analysis. In turn, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was adopted to assess the level of renewable energy development in the European Union countries. Both these methods and the extended statistical analysis were applied to determine the state of renewable energy development in the European Union countries in the studied period and to divide the Member States into classes with different levels of development. The results of the study showed that the EU countries are characterized by significant differences in the development of RES during the period in question. The unquestionable leaders in this respect are Sweden, Austria, Finland, and Latvia. Based on the findings, it is possible to evaluate the effects of activities related to renewable energy development and to prepare assumptions for future activities. Additionally, both the research and its findings broaden the knowledge of the directions of renewable energy development in individual European Union countries. This is particularly important in the context of changes related to the need to reduce harmful substance emissions and the implementation of the European Green Deal idea.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2301
Author(s):  
Yun-Sung Cho ◽  
Yun-Hyuk Choi

This paper describes a methodology for implementing the state estimation and enhancing the accuracy in large-scale power systems that partially depend on variable renewable energy resources. To determine the actual states of electricity grids, including those of wind and solar power systems, the proposed state estimation method adopts a fast-decoupled weighted least square approach based on the architecture of application common database. Renewable energy modeling is considered on the basis of the point of data acquisition, the type of renewable energy, and the voltage level of the bus-connected renewable energy. Moreover, the proposed algorithm performs accurate bad data processing using inner and outer functions. The inner function is applied to the largest normalized residue method to process the bad data detection, identification and adjustment. While the outer function is analyzed whether the identified bad measurements exceed the condition of Kirchhoff’s current law. In addition, to decrease the topology and measurement errors associated with transformers, a connectivity model is proposed for transformers that use switching devices, and a transformer error processing technique is proposed using a simple heuristic method. To verify the performance of the proposed methodology, we performed comprehensive tests based on a modified IEEE 18-bus test system and a large-scale power system that utilizes renewable energy.


2014 ◽  
Vol 971-973 ◽  
pp. 337-340
Author(s):  
Gui Ling Ju ◽  
Wei Hai Sun ◽  
Jian Du ◽  
Yun Chang Hang

This paper deals with the adaptive feedback control for the nonholonomic systems with strongly nonlinear uncertainties. The state-input scaling technique and back-stepping approach are used to design the output feedback controller. In order to make the state scaling effective, a new switching control strategy based on the output measurement of the first subsystem is employed.


2010 ◽  
Vol 12 (2) ◽  
pp. 165-192 ◽  
Author(s):  
Natalie Florea Hudson ◽  
Michael J. Butler

2021 ◽  
Vol 12 (3) ◽  
pp. 631
Author(s):  
Sergey BESPALYY

The growth of renewable energy sources (RES) shows the desire of the government of Kazakhstan to meet challenges that affect the welfare and development of the state. National targets, government programs, policies influence renewable energy strategies. In the future, renewable energy technologies will act as sources of a green economy and sustainable economic growth. The state policy in the field of energy in Kazakhstan is aimed at improving the conditions for the development and support of renewable energy sources, amendments are being made to provide for the holding of auctions for new RES projects, which replaces the previously existing system of fixed tariffs. It is expected that the costs of traditional power plants for the purchase of renewable energy will skyrocket, provided that the goals in the field of renewable generation are achieved. This article provides an assessment of international experience in supporting renewable energy sources, as well as analyzes the current situation in the development of renewable energy in Kazakhstan and the impact on sustainable development and popularization of the «green» economy. The study shows that by supporting the development of renewable energy sources, economic growth is possible, which is achieved in an environmentally sustainable way.


Sign in / Sign up

Export Citation Format

Share Document