Note: [1140] Reference EPFL-ARTICLE-227341 Record created on 2017-04-04, modified on 2017-04-05
There are few methods to archive improved voltage waveform in synchronous hydro generators, while keeping noise and vibrations at satisfactory levels. The number of stator slots, winding arrangement, slot skew and damper bar pitch can all effect the quality of the waveform, but each has both advantages and disadvantages. This method review options, focusing on the slot skewing method.
Note: [1155] Reference EPFL-ARTICLE-229983 Record created on 2017-07-19, modified on 2017-07-20
A rehabilitation scheme at the more than 100 year-old Fully hydro scheme, where the penstock had shown signs of ageing, has involved converting the original single power station into a cascade of three plants, which have been integrated in a municipal water supply system. This paper presents the main stages of the rehabilitation studies, the reasons for the solution adopted, as well as an overview of the construction challenges. The scheme is now nearing completion, with the last small plant scheduled to be commissioned in December.
Reservoir sedimentation is an ongoing issue, which endangers the sustainability of reservoirs. As well as reducing the capacity of a reservoir, sedimentation causes damage to hydraulic structures such as turbine intakes and bottom outlets. In addition, downstream problems related to the river’s ecosystem are also observed. Venting turbidity currents is one method for managing sedimentation problems. This paper presents the main conditions for venting, as well as examining its application and efficiency in various scenarios.
The authors present the current context for energy transition and hydropower development in Switzerland, summarizing the activities in the field of hydropower infrastructure research carried out over the past three years and presenting the development objectives for the coming four years. The focus is on increasing operational flexibility and winter production. The plan includes three large scale pilot projects, the first on recently commissioned small hydro schemes, the second on sediment release through the powerhouses, and the third being a multidisciplinary project in the multi-reservoir multi-powerplant scheme operated by Kraftwerke Oberhasli in the Bernese Oberland.
The Zambezi river basin, one of the largest in Africa, holds significant hydropower potential, which has yet tobe exploited. To make the most of this opportunity and address the challenges it poses, local Stakeholders must coordinate efforts, politically, institutionally, and technically. While recent progress on these fronts has been remarkable, legitimate concerns regarding data ownership, maintenance, and analysisstill need to be addressed. This paper presents the African Dams Project's (ADAPT) water resources database, which relies on open source technology and is based on three key ideas: the total empowerment of stakeholders; the association of valuable analysis tools and data; and, an adaptable and simple architecture.
Study of the behaviour of CFRD (concrete face rockfill dams) founded on active faults. It is generally accepted that embankment dams founded on active faults exhibit good behaviour during the rupture of a fault, whereas concrete gravity dams may be more seriously affected if significant differential movements occur at their foundations. However, experience with CFRDs subjected to fault displacements at their foundation is limited and therefore it is important to analyse the likely response of CFRDs in such a scenario.
Cameroon’s electricity sector is undergoing significant changes. Before 1974, electricity was supplied by many different companies until they were nationalized and merged into a single, vertically integrated company that had responsibility for production, transmission, distribution and electricity retail sales. This monopolistic organization has, however, certain limitations and the national company was privatized in 2001. This article presents assessment of the hydro sector, previous and current legislation, and opportunities for private investors.
Anumber of major hydropower schemes have been developed in the lambezi river basin to ensure astable energy output. Although this main objective is well met, there is considerable scope to optimize operation of the plants. This paper presents the results of an integrated water resource management study, called the African Dams Project (ADAPTl, and focuses on how hydropower schemes can be adopted to meet environmental needs.
Experiments are conducted using a 10 MW Kaplan hydropower machine with a PowerFormerT M generator, the Porjus U9 research machine. This machine is outfitted with an extensive array of sensors to det ...
Sediment erosion not only reduces efficiency and life of hydropower turbines but also causes problems in operation and maintenance. Several factors are responsible for this erosion in hydro turbine ...
Hydropower has been a source of clean, renewable electricity in the USA for more than 100 years. Today, approximately 2500 US dams provide 78 GW of conventional and 22 GW of pumped-storage hydropower. In contrast, another approximately 80 000 dams in the USA do not include hydraulic turbine equipment and provide non-energy related services, such as flood control, water supply, navigation, and recreation.
