In recent years, the European and in particular the German transmission system have been faced with a significant increase of grid congestion issues. Contemporary congestion management heavily relies on redispatch of ...
详细信息
ISBN:
(纸本)9783800749546
In recent years, the European and in particular the German transmission system have been faced with a significant increase of grid congestion issues. Contemporary congestion management heavily relies on redispatch of large-scaled conventional power plants. This needs to be reconsidered as the power system develops towards distributed generation and increased importance of flexibility. This paper presents concepts on how virtual power plants (VPP) of aggregators could be incorporated in redispatch procedures. To this end, the technical redispatch potential of VPPs is calculated by an optimization-based methodology. In the context of this paper, a VPP may consist of flexible generators, storage systems, electric mobility and flexible loads. The effectiveness of the methodology is demonstrated by applying it to case studies considering different grid structures, VPP combinations and installed power of flexible generation and load.
Distinguished with the traditional tooth flank of spiral bevel gears, an accurate spherical involute tooth profile is of obvious advantages for the design and manufacture. For obtaining the gear model with enough toot...
详细信息
Distinguished with the traditional tooth flank of spiral bevel gears, an accurate spherical involute tooth profile is of obvious advantages for the design and manufacture. For obtaining the gear model with enough tooth flank accuracy, simulation and optimization methodologies of computer numerical control-milling model are proposed. Initially, it gives an identification of the spherical involute tooth flank based on an improved formation theory. A universal simulation machining of the universal multi-axis computer numerical control-milling center is proposed to obtain an initial model. Then, in order to get/for getting improved tooth flank accuracy of the initial gear model, it presents some optimization methods included in the applications which are (1) non-uniform rational B-spline reconstruction by the Skinning method and (2) an overall interpolation based on Energy method. Finally, some given numerical examples are utilized to verify the form error of tooth flank. In addition, a closed-loop experiment scheme is provided to verify the validity of proposed methods.
Artificial neural network models that predict the Charpy-impact toughness values as a function of composition, heat treatment, and shielded metal arc welding process parameters were coupled with multipurpose optimizat...
详细信息
Artificial neural network models that predict the Charpy-impact toughness values as a function of composition, heat treatment, and shielded metal arc welding process parameters were coupled with multipurpose optimization software. This coupled model was used to optimize the carbon, nickel, and manganese concentrations in a weld to achieve a maximum toughness of 120 J at -60degreesC. The coupled model used linear and nonlinear techniques to explore the possible combinations of carbon, manganese, and nickel concentrations for a given set of welding process parameters. An optimum weld metal composition was achieved only with nonlinear methods. The number of iterations and the exploration of input parameter space varied depending upon the type of nonlinear technique. The predicted weld metal composition was in agreement with published results.
暂无评论