Search results for "motors"

Age affects myosin relaxation states in skeletal muscle fibers of female but not male mice

2018

The recent discovery that myosin has two distinct states in relaxed muscle–disordered relaxed (DRX) and super-relaxed (SRX)–provides another factor to consider in our fundamental understanding of the aging mechanism in skeletal muscle, since myosin is thought to be a potential contributor to dynapenia (age-associated loss of muscle strength independent of atrophy). The primary goal of this study was to determine the effects of age on DRX and SRX states and to examine their sex specificity. We have used quantitative fluorescence microscopy of the fluorescent nucleotide analog 2′/3′-O-(N-methylanthraniloyl) ATP (mantATP) to measure single-nucleotide turnover kinetics of myosin in skinned skel…

Fracture Mechanics of Collagen Fibrils: Influence of Natural Cross-Links

2013

AbstractTendons are important load-bearing structures, which are frequently injured in both sports and work. Type I collagen fibrils are the primary components of tendons and carry most of the mechanical loads experienced by the tissue, however, knowledge of how load is transmitted between and within fibrils is limited. The presence of covalent enzymatic cross-links between collagen molecules is an important factor that has been shown to influence mechanical behavior of the tendons. To improve our understanding of how molecular bonds translate into tendon mechanics, we used an atomic force microscopy technique to measure the mechanical behavior of individual collagen fibrils loaded to failu…

Diffusion Acceleration in Randomly Switching Sawtooth Potential

2005

We investigate an overdamped Brownian motion in symmetric sawtooth periodic potential switched by Markovian dichotomous noise between two configurations. The two configurations differ each other by a translation of half of period. The calculation of the effective diffusion coefficient is reduced to the mean first‐passage time problem, and we obtain the exact expression valid for arbitrary mean rate of switchings and arbitrary intensity of white Gaussian noise. We find the area at parameters plane where acceleration of diffusion in comparison with the free diffusion case takes place.

Automotive Brushless Motor Powered by Fuel Cell

2014

Active Disturbance Rejection Control of Synchronous Reluctance Motors

2020

This paper describes how the ADRC (Active Disturbance Rejection Control) strategy can be successfully applied to SynRM (Synchronous Reluctance Motor) drives. The ADRC is an adaptive robust extension of the input-output Feedback Linearization Control (FLC). Its main feature is that the nonlinear transformation of the state is computed on-line and not by using the model. As a consequence, any unmodelled dynamics or uncertainty of the parameters can be addressed. The control strategy has been verified successfully with experimental tests confirming the high dynamic response of the drive.

A Cogging Torque Minimization Procedure for Interior Permanent Magnet Synchronous Motors Based on a Progressive Modification of the Rotor Lamination …

2022

This article describes a simple cogging torque minimization procedure for interior permanent magnet synchronous machines (IPMSMs), consisting of a progressive modification of the rotor lamination geometry. This procedure can be generalized for the main topologies of PMSM, independently of the number of stator slots or the location of the permanent magnets. For this purpose, a basic IPMSM structure is analyzed by means of the FEM (finite element method) approach, and then, several other IPMSM geometries, obtained by adequately modifying the rotor lamination geometry of the basic IPMSM model without changing its stator configuration, are proposed and discussed. The trends of the cogging torqu…

A dq axis theory of the magnetic, thermal, and mechanical properties of Curie motor

2011

A dq axis theory of a thermomagnetic Curie motor is presented. This theory allows one to estimate the performances of a Curie motor from its geometrical, magnetic, and thermal properties. The proposed approach shows that the thermomagnetic Curie motor is equivalent from a magnetic point of view to a dc electric machine. The physical meaning of the parameters used in the dq theory of Curie motor is explicated. The theory is validated by using experimental data.

Enhanced flexible algorithm for the optimization of slot filling factors in electrical machines †

2020

The continuous development in the field of industrial automation and electric mobility has led to the need for more efficient electrical machines with a high power density. The improvement of electrical machines’ slot filling factors is one of the measures to satisfy these requirements. In recent years, this topic has aroused greater interest in the industrial sector, since the evolution of the winding technological manufacturing processes allows an economically sustainable realization of ordered winding arrangements, rather than random ones. Moreover, the manufacture of electrical machines’ windings must be preceded by an accurate design phase in which it is possible to evaluate the maximu…

A model of a linear synchronous motor based on distribution theory

2012

The fundamental idea of this paper is to use the distribution theory to analyze linear machines in order to include in the mathematical model both ideal and non ideal features. This paper shows how distribution theory can be used to establish a mathematical model able to describe both the ordinary working condition of a Linear Synchronous Motor (LSM) as well the role of the unavoidable irregularities and non ideal features.

Automatic detection of thermal anomalies in induction motors

2021

The paper proposes a methodology based on Artificial Intelligence techniques for the automatic detection of abnormal thermal distributions in electric motors, to rapidly identify pre-faults or fault conditions. The proposed approach, applied to induction motors of different sizes, installed in waterworks plants, is based on the execution of Thermographic Non-Destructive Tests, which allow identifying abnormal operating conditions without interrupting the ordinary working conditions of the system. Thermographic images of induction motors are acquired at the installation site and with perspectives visible to the operator, which are sometimes partially obstructed. These thermographic images ar…