Rolls-Royce Motor Cars

About: Rolls-Royce Motor Cars is a based out in . It is known for research contribution in the topics: Turbine & Gas compressor. The organization has 3845 authors who have published 4934 publications receiving 58973 citations. The organization is also known as: Rolls-Royce Motor Cars Limited.

Tensile Fillet Stresses in Loaded Projections

Abstract: The loaded projection is an essential feature of practically every machine and structure—the screw thread, gear tooth, and simple cantilever are examples. The strength frequently depends on the fil...

Multiscale fatigue life prediction model for heterogeneous materials

Abstract: SUMMARY A multiscale fatigue life prediction model is developed for heterogeneous materials. The proposed model combines a two-scale asymptotic homogenization approach in time with a ‘block cycle jump’ technique into a unified temporal multiscale framework that can be effectively utilized for arbitrary material architectures and constitutive equations of microphases. The unified temporal multiscale approach in combination with a spatial multiscale approach based on the reduced order homogenization is characterized for high temperature ceramic matrix composites. Copyright © 2012 John Wiley & Sons, Ltd.

Modulated Model Predictive Control for Modular Multilevel Converters With Easy Implementation and Enhanced Steady-State Performance

Abstract: Model predictive control (MPC) is widely employed in voltage-source converters due to its fast-dynamic response, straightforward realization, and flexible inclusion of multiobjective regulation. However, the MPC has several technical challenges when it comes to the control of modular multilevel converters, such as computational complexity, variable switching frequency, poor steady-state performance as well as tedious weighting factor selection. To solve these problems, this article proposes a new modulated MPC method, which can directly acquire the optimal modulation references at every sampling period based on the duty cycles of two fixed voltage levels. The optimal modulation references are then fed into the modulation stage to generate gate signals. Therefore, the proposed method is easy to implement with a very low calculation burden, which is independent of the number of submodules (SMs). The switching state or voltage-level evaluation, cost function calculation, and weighting factor selection are eliminated as well. Because of the inherent circulating current suppression capability without limitations and modulation stage, this method has a satisfactory steady-state performance and evenly distributed switching loss for every SM. The effectiveness and performance of the proposed method are verified by experimental results.