Uncertain Saturated Discrete‐Time Sliding Mode Control for A Wind Turbine Using A Two‐Mass Model

The aim of this paper is to propose a new design variable speed wind turbine control by discrete‐time sliding mode approach. The control objective is to obtain a maximum extraction of wind energy, while reducing mechanical loads and rotor speed tracking combined with an electromagnetic torque. For this application, we designed a discrete time sliding mode control using the equivalent discrete time reaching law. Furthermore, a systematic and improved design procedure for uncertainties discrete‐time sliding mode control (SMC) with saturation problem is provided in this paper. The saturation constraint is reported on inputs vector. LMI technique and polytopic models are used in the design of the switching surface. To achieve some performance requirements and good robustness, in the sliding mode, the pole clustering method is investigated. Based on the unit vector control approach, a robust control is developed, then, to direct and maintain the system states onto the sliding manifold in finite time. Finally, a systematic design procedure for DSMC required to achieve a given performance level is provided and its effectiveness is varied by applying it to variable speed wind turbine systems.     

Maintaining consistency between CAD elements in collaborative design using association management and propagation

The complete definition of a product often requires the collaboration of various partners. Data sharing and exchange between partners has thus become an important task throughout a product's entire life cycle. Even while subsets of the product definition are exchanged (as work packages) and modified by various partners, the global product definition must remain consistent. This paper focuses on maintaining consistency between Computer-Aided Design (CAD) work packages and the global product Digital Mock-Up (DMU). The approach is designed to ensure better management of the associations between objects when a work package is extracted from the global DMU, modified by a partner, sent back to the originator and then re-inserted into the global DMU, which must be modified in turn so as to maintain consistency. To this end, we propose an association management model for the digital mock-up (Digital Mock-up Association Management Model, DMU-AMM) that transposes the associations that exist between a DMU and a work package, including package extraction and modifications, to ultimately guide the evolution of the DMU so as to reconcile the associations between a modified DMU and the modified work package and there by maintain consistency.