Search results for "Induction Motor"

A nonlinear observer for rotor flux estimation considering magnetic saturation effects in induction motor drives

2015

This paper proposes a non-linear observer for In- duction Machine (IM) drives which takes into consideration the saturation effects. The non-linear observer is based on an original formulation of the dynamic model of the IM taking into consideration the magnetic saturation of the iron core. A Lyapunov based convergence analysis is proposed in order to suitably compute the observer gain guaranteeing the stability of the observer. The proposed non-linear observer has been tested in numerical simulation and experimentally on a suitably developed test set-up. Its behaviour has been compared to that obtained with a classic Full-Order Luenberger Observer (FOLO) in variable flux working conditions…

A Nonlinear Observer for Rotor Flux Estimation of Induction Motor Considering the Estimated Magnetization Characteristic

2017

This paper proposes a nonlinear observer for induction machine drives based on space-vector dynamic model of induction machine, expressed in state form, which presents the peculiarity of taking into consideration the magnetic saturation of the iron core. This observer is particularly suitable in order to obtain high accuracy in rotor flux estimation, in both amplitude and phase position, during working conditions characterized by varying flux, among which the most important are those during electrical losses minimization. A Lyapunov-based convergence analysis is proposed in order to suitably compute the numerical observer gain guaranteeing the convergence of the estimation error. The propos…

Linear flux observers for induction motors with quadratic Lyapunov certificates

2016

International audience; We propose a full order Linear Time-Varying (LTV) Luenberger observer for the rotor flux estimation of an induction motor. Introducing a suitable reduced-order Linear-Time-Invariant (LTI) system that is always observable and controllable, we show that any arbitrary LTI design and its quadratic Lyapunov certificates can be lifted to the higher-order original LTV dynamics obtaining the same certificates. As a result, we show that arbitrary global uniform exponential bounds can be imposed on the estimation error, regardless of the rotor speed. Then applying a suitable order reduction technique, we build a reduced observer providing the same guarantees. We also establish…

Drivetrain design optimization for electrically actuated systems via mixed integer programing

2015

The proposed paper presents a method to optimally select components of a drivetrain for an electrically actuated machine. A simple mathematical model of the machine is established and inequality constraints which determine the choice of drivetrain components are formulated. Elements to be picked (namely, a motor, a gearbox, and a drive) are taken from a discrete set of data provided in the catalogs of industrial motors and drives manufacturers. By solving an optimization problem, a combination of components which both satisfy design requirements and minimize the total drivetrain cost is selected. The operation of the selected drivetrain is verified against the motor loadability curves. In a…

Parameters identification of induction motor dynamic model for offshore applications

2014

The paper presents a technique to identify parameters of the LuGre dynamic friction model applied to represent mechanical losses of an induction motor. This method is based on Artificial Neural Networks (ANNs) system identification which is able to estimate parameters of nonlinear mathematical models. Within the presented approach, the network is first trained to associate model parameters with predicted friction torque, being given the reference motor speed. When this process completes, the inverse operation is performed and the network delivers estimated parameters of the model based on the reference friction torque. These parameters are then integrated with the dynamic model of the induc…

Hybrid model of an inventer-induction motor system

1969

A model of the three-phase bridge inverter with a wide range of validity is proposed. This model can be used for the simulation of the inverter induction motor system on a hybrid computer or an analogue computer. In the latter case it is necessary to achieve a logical device which realizes the inverter model. After a block diagram for the simulation of the inverter induction motor system is illustrated as well as the circuital diagram of the device which simulates the inverter. Finally the authors describe the tests carried out in order to verify the validity of the inverter model and the correct operating of the device which simulates the inverter.

A Rotor Flux and Speed Observer for Sensorless Single-Phase Induction Motor Applications

2012

It is usual to find single-phase induction motor (SPIM) in several house, office, shopping, farm, and industry applications, which are become each time more sophisticated and requiring the development of efficient alternatives to improve the operational performance of this machine. Although the rotor flux and rotational speed are essential variables in order to optimize the operation of a SPIM, the use of conventional sensors to measure them is not a viable option. Thus, the adoption of sensorless strategies is the more reasonable proposal for these cases. This paper presents a rotor flux and rotational speed observer for sensorless applications involving SPIMs. Computer simulations and the…

Spin-up instability of electromagnetically levitated spherical bodies

2000

Stability of a solid sphere in both uniform and linear alternating magnetic fields is considered with respect to virtual rotations. When the frequency of the alternating magnetic field exceeds a certain critical threshold depending on the configuration of the field, the sphere is found to spin up around a horizontal axis. The physical mechanism of this instability is the same as that of operation of a single-phase induction motor. Sufficiently small rotational disturbances can be completely suppressed by imposing an axial steady magnetic field of strength comparable to that of the alternating field. Nonlinear stability analysis shows that for sufficiently high frequencies, spin-up can be ca…

Rotor “Nonsynchronous” Control Of Induction Motors. Part I: Determination Of A Mathematical Model

1983

Electromechanical properties of a disc‐type salient‐pole brushless DC motor with different pole numbers

2003

A brushless, permanent magnet, three‐phase disc‐type salient‐pole DC motor with co‐axial flux in the stator is considered. Electromechanical properties of a basic eight‐pole motor are compared with those for a 16‐pole one of the same volume, in order to contrast the two potential candidates for variable‐speed, low‐cost drives. As a basis of the comparative analysis, 3D FEM magnetic field modelling and circuit analysis considering an electronic commutator are employed. Increasing the number of poles results in unfavourable raising in the switching frequency. The eight‐pole motor construction has been shown in simulations to have higher efficiency and lower power losses than its 16‐pole count…