The reliability of modern onshore wind turbines is at present at an acceptable level. This means ... more The reliability of modern onshore wind turbines is at present at an acceptable level. This means that, assuming 100 % site accessibility and implementing a well-organised efficient maintenance strategy, most onshore wind turbines show availability levels of above 98 %. In other words the yearly downtime due to service and repair is less than 1 week.
The European Academy of Wind Energy (eawe), representing universities and institutes with a signi... more The European Academy of Wind Energy (eawe), representing universities and institutes with a significant wind energy programme in 14Â countries, has discussed the long-term research challenges in wind energy. In contrast to research agendas addressing short- to medium-term research activities, this eawe document takes a longer-term perspective, addressing the scientific knowledge base that is required to develop wind energy beyond the applications of today and tomorrow. In other words, this long-term research agenda is driven by problems and curiosity, addressing basic research and fundamental knowledge in 11Â research areas, ranging from physics and design to environmental and societal aspects. Because of the very nature of this initiative, this document does not intend to be permanent or complete. It shows the vision of the experts of the eawe, but other views may be possible. We sincerely hope that it will spur an even more intensive discussion worldwide within the wind energy commu...
International Journal of Electrical Engineering Education, 1976
The article has particular relevance to designing electrical engineering laboratories in developi... more The article has particular relevance to designing electrical engineering laboratories in developing countries and discusses some of the problems of planning the power circuit distribution system. Tables of power supplies, outlets and stabilisation equipment suitable for a laboratory are presented with a comprehensive bibliography.
3rd IET International Conference on Power Electronics, Machines and Drives (PEMD 2006), 2006
Abstract The study describes a power electronic conversion and control scheme for a 8.5 kW, multi... more Abstract The study describes a power electronic conversion and control scheme for a 8.5 kW, multi-coil, linear, permanent magnet, air-cored generator for direct-drive wave energy conversion developed for a wave energy Test Rig developed for the New & Renewable ...
Proceedings of the 41st International Universities Power Engineering Conference, 2006
ABSTRACT The paper presents an analysis and simulation study of the power extraction capability o... more ABSTRACT The paper presents an analysis and simulation study of the power extraction capability of a direct drive wind turbine realised using a modular permanent magnet generator connected to the 11 kV grid via a cascaded multilevel voltage source inverter (CMVSI) without an interface transformer. The DC link in each of the CMVSI modules is supplied by a pair of generator coils connected through uncontrolled bridge rectifiers. The DC link voltage is determined by the required real and reactive power output to the grid, which constrains the available speed range of the turbine, limiting the power extraction at low wind speeds
2007 IEEE International Electric Machines & Drives Conference, 2007
... The loops in characteristic is shared with the doubly-fed slip ring ... offers brushless oper... more ... The loops in characteristic is shared with the doubly-fed slip ring ... offers brushless operation. ... appropriately designed BDFM rotor, which implies thatof the two harmonic fields are 1110 Hz (20 pole) and 130 wound BDFM rotors need less copper area than DFIM Hz (16 pole). ...
4th IET International Conference on Power Electronics, Machines and Drives (PEMD 2008), 2008
ABSTRACT Direct drive power take off eliminates the need for a mechanical interface to match the ... more ABSTRACT Direct drive power take off eliminates the need for a mechanical interface to match the low speed reciprocating motion of a wave device to high speed rotational motion of conventional electrical generators. However, direct drive generators are physically large and heavy due to the low velocities encountered. Iron cored PM machines suffer from magnetic attraction forces which is challenging for the structural and bearing design. An air-cored machine solves the issue of magnetic attraction forces, which will benefit the mechanical design. The performance of an air-cored PM tubular machine is investigated in this paper under displacements typical of a wave energy device.
IET International Conference on Agile Manufacturing (ICAM 2007), 2007
ABSTRACT Much research has concentrated on understanding the supply chain process and inter-compa... more ABSTRACT Much research has concentrated on understanding the supply chain process and inter-company relationships in order to develop standardised methods for controlling and managing the facade procurement procedure. This paper concentrates on analysing potential gaps in the supply chain process related to developing and managing cost plans related to the facade sector in UK construction industry. The methodology presented in this research will be based on developing an agile manufacturing system that will be implemented in stages to cope with the continuously changing demands of the facade design, particularly related to an aesthetically demanding project. The different stages that will be discussed in this paper are summarised under technology implementation and integration, knowledge management, and finally an integrated agile system. The main aim of the system is to allow the architect, the manufacturer and the installer to achieve a cost effective balance between the aesthetics, the performance, product manufacture and the buildability of the facade, PSP Ltd. will be used as an example to demonstrate the implementation and techniques that will be discussed in this paper.
The reliability of modern onshore wind turbines is at present at an acceptable level. This means ... more The reliability of modern onshore wind turbines is at present at an acceptable level. This means that, assuming 100 % site accessibility and implementing a well-organised efficient maintenance strategy, most onshore wind turbines show availability levels of above 98 %. In other words the yearly downtime due to service and repair is less than 1 week.
The European Academy of Wind Energy (eawe), representing universities and institutes with a signi... more The European Academy of Wind Energy (eawe), representing universities and institutes with a significant wind energy programme in 14Â countries, has discussed the long-term research challenges in wind energy. In contrast to research agendas addressing short- to medium-term research activities, this eawe document takes a longer-term perspective, addressing the scientific knowledge base that is required to develop wind energy beyond the applications of today and tomorrow. In other words, this long-term research agenda is driven by problems and curiosity, addressing basic research and fundamental knowledge in 11Â research areas, ranging from physics and design to environmental and societal aspects. Because of the very nature of this initiative, this document does not intend to be permanent or complete. It shows the vision of the experts of the eawe, but other views may be possible. We sincerely hope that it will spur an even more intensive discussion worldwide within the wind energy commu...
International Journal of Electrical Engineering Education, 1976
The article has particular relevance to designing electrical engineering laboratories in developi... more The article has particular relevance to designing electrical engineering laboratories in developing countries and discusses some of the problems of planning the power circuit distribution system. Tables of power supplies, outlets and stabilisation equipment suitable for a laboratory are presented with a comprehensive bibliography.
3rd IET International Conference on Power Electronics, Machines and Drives (PEMD 2006), 2006
Abstract The study describes a power electronic conversion and control scheme for a 8.5 kW, multi... more Abstract The study describes a power electronic conversion and control scheme for a 8.5 kW, multi-coil, linear, permanent magnet, air-cored generator for direct-drive wave energy conversion developed for a wave energy Test Rig developed for the New & Renewable ...
Proceedings of the 41st International Universities Power Engineering Conference, 2006
ABSTRACT The paper presents an analysis and simulation study of the power extraction capability o... more ABSTRACT The paper presents an analysis and simulation study of the power extraction capability of a direct drive wind turbine realised using a modular permanent magnet generator connected to the 11 kV grid via a cascaded multilevel voltage source inverter (CMVSI) without an interface transformer. The DC link in each of the CMVSI modules is supplied by a pair of generator coils connected through uncontrolled bridge rectifiers. The DC link voltage is determined by the required real and reactive power output to the grid, which constrains the available speed range of the turbine, limiting the power extraction at low wind speeds
2007 IEEE International Electric Machines & Drives Conference, 2007
... The loops in characteristic is shared with the doubly-fed slip ring ... offers brushless oper... more ... The loops in characteristic is shared with the doubly-fed slip ring ... offers brushless operation. ... appropriately designed BDFM rotor, which implies thatof the two harmonic fields are 1110 Hz (20 pole) and 130 wound BDFM rotors need less copper area than DFIM Hz (16 pole). ...
4th IET International Conference on Power Electronics, Machines and Drives (PEMD 2008), 2008
ABSTRACT Direct drive power take off eliminates the need for a mechanical interface to match the ... more ABSTRACT Direct drive power take off eliminates the need for a mechanical interface to match the low speed reciprocating motion of a wave device to high speed rotational motion of conventional electrical generators. However, direct drive generators are physically large and heavy due to the low velocities encountered. Iron cored PM machines suffer from magnetic attraction forces which is challenging for the structural and bearing design. An air-cored machine solves the issue of magnetic attraction forces, which will benefit the mechanical design. The performance of an air-cored PM tubular machine is investigated in this paper under displacements typical of a wave energy device.
IET International Conference on Agile Manufacturing (ICAM 2007), 2007
ABSTRACT Much research has concentrated on understanding the supply chain process and inter-compa... more ABSTRACT Much research has concentrated on understanding the supply chain process and inter-company relationships in order to develop standardised methods for controlling and managing the facade procurement procedure. This paper concentrates on analysing potential gaps in the supply chain process related to developing and managing cost plans related to the facade sector in UK construction industry. The methodology presented in this research will be based on developing an agile manufacturing system that will be implemented in stages to cope with the continuously changing demands of the facade design, particularly related to an aesthetically demanding project. The different stages that will be discussed in this paper are summarised under technology implementation and integration, knowledge management, and finally an integrated agile system. The main aim of the system is to allow the architect, the manufacturer and the installer to achieve a cost effective balance between the aesthetics, the performance, product manufacture and the buildability of the facade, PSP Ltd. will be used as an example to demonstrate the implementation and techniques that will be discussed in this paper.
Uploads