5 research outputs found
Parameter identification of PMSM using EKF with temperature variation tracking in automotive application
International audiencePermanent magnet synchronous machine is widely used for electric vehicles traction because of its high power density and its efficiency on a large flux weakening range. This paper focuses in particular on the estimation of PMSM parameters using EKF, we present a study assessing the temperature variations impact on the behavior of PMSM motor, and therefore we propose to estimate the temperature-dependent parameters. The main contribution in this work is an effective method for estimating parameters or their temperature variation, makes it possible to study and to avoid performance degradation by tracking and adapting the parameters in torque observer in order to find the same performance at any temperature and can be also used for thermal monitoring, which allows for better availability of motor, without causing damage, however, the knowledge of degradation mechanisms also gives insight for the design of this machine. Nowadays, there are essentially maps of reference currents according to the torque and speed that are used by car manufacturers and no account is then given of the parameter variations. The effectiveness of the proposed estimation method verified by both simulation and experiment
Magnetic field effect on nonlocal resonance frequencies of structure-based filter with periodic square holes network
International audienceIn this paper, we investigate the magnetic field, thermal loads and small scale effects on the dynamics vibration of a nanobeam structure composed of a rectangular configuration perforated with periodic square holes network and subjected to axial magnetic field based on Euler–Bernoulli beam model (EBM) and Timoshenko beam model (TBM). The developed resonance frequencies expressions are derived by modifying the standard equations of dynamics beam vibration. The small scale effect is adopted via the Eringen's nonlocal theory while the coupled governing equations are obtained and solved using analytical solution method in order to determine the resonance frequency of perforated nanobeam. It is found that the resonance frequency change, the magnetic field intensity, the thermal loads and small scale effects are in dependence with geometrical parameters such as size and number of holes. Therefore, these results are discussed for the investigation of the structure dynamic deformation and compared with literature results where new remarks are deduced and presented with detail for a proper design of M/NEMS structures
Mathematical model for the adsorption-induced nonlocal frequency shift in adatoms-nanobeam system
International audiencehis paper models and investigates the resonance frequency shift induced by the adsorption phenomena for an adatoms-nanobeam system including the small scale effect as well as rotary inertia and shear distortion effects. The Lennard-Jones (6–12) type potential is used to determine the adsorption-induced energy owing van der Waals (vdW) interaction mechanism between adatom-adatom and adatom-substrate. The small scale effect is introduced by using Eringen's nonlocal elasticity theory while the explicit expressions of inertia moment and shear force are derived from the standard Timoshenko beam equations in which the residual stress effect is accounted as an additive axial load. Numerical results showed that the resonance frequency shift is depended on each of the adsorption density, mode number and small scale effects. Thus, numerical results are discussed in detail for a proper analysis of dynamic vibration behavior of adatoms-nanobeam systems which are of interest in the development of mass sensing devices