Funded Project
Start Date : 01 Jan 2015-01 Jan 2015
The sustainable development of Sinai is of true national interest. This call for proposals and the recent Sinai for New Egypt conference are examples of initiatives aimed at putting forth the general views regarding different means of socioeconomic development in Sinai. Initiatives such as DESERTEC have highlighted the substantial wind and solar energy resources of Sinai. Exploiting these resources can stimulate the economy, provide new job opportunities, as well as preserve Sinai’s environment. Sinai’s strategic location as a link between the European Union, Middle East and North Africa makes it a strategic partner in any initiative between these regions, such as an interconnected electrical grid. Wind power is now the world's fastest growing renewable energy source and has also become one of the most rapidly expanding industries. High power wind generators may soon be the most economical way to produce renewable energy on a large scale. Among the different types of wind generators, direct-drive permanent magnet (PM) generators are emerging as an effective means of wind energy conversion in medium and large power ratings as they not only provide higher efficiency and annual energy production but also reduce the operational and maintenance cost. These gearless generators are characterized by their large dimensions and weight, which makes their modular construction of significant interest. Additionally, two of the main metrics in the design of such generators are torque quality and cost. High magnitude torque ripples due to cogging torque and the stator winding’s MMF reaction yield serious vibration and acoustic noise which, in turn, affect the lifetime of the drive train. Moreover, at low turbine speeds, the corresponding developed torque is very low hence, cogging torque can consequently lead to complete failure of the PM generator start-up. Thus, minimizing torque ripples is an important aspect in designing PM generators. Recent work by the PI, although lacking experimental validation due to funding constraints, has resulted in a novel PM generator architecture using a non-overlap single layer winding resulting in a cost-effective modular design with numerous merits, including ease of manufacturing, reduced torque ripples, high voltage quality, and high fault tolerant capability [3]. The objective of this proposal is to develop a complete wind energy conversion system based on a direct-drive configuration using an improved performance generator and generator-friendly current waveform front-end converter. Torque ripples due to both cogging torque and air-gap spatial harmonics are significantly reduced compared with existing architectures. A generator-friendly current waveform front-end converter based on a current source converter (CSC) topology is also proposed. The CSC has shown superior performance to its voltage source counterpart in medium and high power applications. It not only provides a generator-friendly current waveform but also offers reliable short-circuit protection. The proposed system topology is expected to maximize energy harvesting by improving the generator power density and efficiency reduce maintenance by improving the torque quality simplify generator construction by employing a single layer non-overlap winding layout and finally, improve system dynamic response under healthy and fault conditions by optimizing the converters’ controllers.