Search results for "stato"
showing 10 items of 384 documents
Speed and rotor flux estimation of induction motors via on-line adjusted extended kalman filter
2006
This paper deals with the estimation of speed and rotor flux of induction motors via Extended Kalman Filter (EKF) with on-line adjusting of the system noise covariance matrix. The predictor of EKF consists of a discrete time model obtained by means of a second order discretization of the original nonlinear model of the induction motor. In order to obtain accurate estimation of the above mentioned variables, the load torque is included in the state variables and then estimated. Three different system noise models are also illustrated and compared each other by simulations carried out in Matlab/Simulink environment. For one of these models, EKF is adjusted on-line by means of an additional PI…
Speed Control of a two-Degrees of Freedom Induction Motor with Rotor Helical Motion for Industrial Applications
2014
This paper describes the realization of a two-degrees of freedom induction motor prototype with rotor helical motion, suitable for several industrial applications as grinders, augers, drilling and milling spindles, robotic arms and drives for medical tools and prostheses. This prototype was realized by combining a three-phase tubular linear induction motor (TLIM) with the stator of a three-phase rotary induction motor, resulting in a THMIM (Tubular Helical Motion Induction Motor). Moreover, a possible simple electrical drive, capable to control the helical motion, is proposed, simulated and analyzed. In particular, the mathematical model of the THMIM has been initially developed and, then, …
A study on the influence of permanent magnet dimensions and stator core structures on the torque of the disc-type brushless DC motor
2000
This paper presents a three-dimensional analysis of the magnetic field distribution for a disc-type, double-sided, permanent magnet, brushless dc motor with a toroidal stator core. Calculations are carried out using the OPERA (3D) package with the TOSCA module. The electromagnetic torque is determined from the Maxwell stress tensor. For comparison, various permanent magnet dimensions and slotless vs. quasi-slotted stator cores are analysed, with an iron powder-resin composite effectively used to imitate the slotted core. The torque ripple is shown to be effectively reduced by appropriate permanent magnet dimensions. The simulation results are in good agreement with experimental data obtaine…
Fast procedure for the calculation of maximum slot filling factors in electrical machines
2017
This paper presents an algorithm for the calculation of maximum slot filling factor in electrical machines. The determination of whole wire cross section that occupy the area of a stator slot is very important in order to estimate the copper losses: The greater is the filling factor the lower are copper losses. The main goal of this paper is to define a simple algorithm for the determination of slot filling factors suitable for all type of slot profiles. The algorithm can be considered as an additional useful tool for the fast design of electrical machine windings.
GA-based Off-Line Parameter Estimation of the Induction Motor Model Including Magnetic Saturation and Iron Losses
2020
This paper, starting from recent papers in the scientific literature dealing with Rotating Induction Motor (RIM) dynamic modelling, as a first step, improves its space-vector dynamic model, including both the magnetic saturation and iron losses; The main original aspects of the proposed model are the following: 1) the magnetic saturation of the iron core has been described on the basis of both current versus flux and flux versus current functions, 3) it includes the iron losses, separating them in hysteresis and eddy current ones, 4) it includes the effect of the load on the magnetic saturation. Afterwards, it proposes an off-line technique for the estimation of electrical parameters of thi…
Transverse flux generators a solution for stand-alone wind mill
2015
The transverse flux generator (TFG) proposed in the paper as a solution for stand-alone wind electric power plants has a topology derived from a reluctance one. This variant has a permanent magnet on the rotor derived for a well-known topology in literature. Consequently, the number of rotor poles becomes double compared with stator one. The paper analyses the possibility of using a multiple modules one phase structure in comparison with poly-phase topology. The costs, torque harmonic content and the different rotor poles' topology are discussed and the conclusions are useful for the plant designer.
Mathematical Model of a PM Brushless Motor with Different Stator-Rotor Pole Pairs Number
2013
The paper presents a mathematical model of Permanent Magnet AC brushless machines (PMSM) having a number of stator poles-obtained via the distribution of the three-phase winding- different from the rotor one, realized by the displacement of the permanent magnets. For these so- called ‘Fractional-Slot’ motors (where few total slots generate high equivalent number of poles) the available mathematical models appear partial and/or incomplete, despite of numerous designing considerations made in literature. In this paper an analytical approach is developed to point out an instantaneous- values mathematical model with concentrated parameters, that can be suitable for control architecture systems …
ROTOR FLUX OPTIMAL ESTIMATION FOR INDUCTION MOTOR CONTROL
2005
Abstract The aim of this paper is to analyze and design reduced order observers of the rotor flux of induction motors. The design requirements are: a) the convergence rate of the rotor flux estimation error; b) a low sensitivity to stator and rotor resistance variations; c) a low sensitivity to errors due to the implementation of the observers on microprocessor-based systems. It is shown that, in order to satisfy the requirements a)-c), it is sufficient to solve a constrained optimization problem according to a criterion in which these requirements appear explicitly. The implementation of the observer is discussed. The observer is tested by simulation and experiments.
Design and Sensitivity Analysis of a Reduced-Order Rotor Flux Optimal Observer for Induction Motor Control
2007
This paper aims to give simple and effective design criteria of rotor flux reduced-order observers for motion control systems with induction motors. While the observer is optimized for rotor and stator resistance variations, a sensitivity analysis is carried out in the presence of variations of all the motor parameters by means of either transfer function from true to observed rotor flux or simulation in a MATLAB-SIMULINK environment, assuming the voltages supplying the motor to be different from those supplying the observer. The sensitivity analysis makes it possible to establish design criteria for the observer in question. The behaviour of the proposed reduced order observer is compared …
Least squares and genetic algorithms for parameter identification of induction motors
2001
Abstract This paper deals with off-line parameter identification of induction motors by means of least square (LS) techniques and genetic algorithms (GA), using stator voltages, stator currents and velocity as input–output data. For analytical identification by LS algorithms, filtering of experimental data is performed by means of anticausal filters. Two models useful for identification are derived in which the products of acceleration and rotor fluxes, usually neglected, are taken into account. The GA-based identification method consists of the determination of the best parameters which match input–output behaviour of the motor. Both methods are investigated and compared by means of experi…