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The end-effects is a well-recognized phenomenon occurring in the linear induction motor (LIM) which makes the analysis and control of the LIM with good performance very difficult and can cause additional significant non-linearities in the model. So, the compensation of parameters uncertainties due to these effects in the control system is very necessary to get a robust speed control. The purpose of this paper is to propose a new technique of LIM end-effects estimation using the inverse rotor time constant tuning in order to compensate the flux orientation error in the indirect field-oriented control (IFOC) control law.

First, the dynamic model of the LIM taking into consideration the end-effects based on Duncan model is derived. Then, the IFOC for LIM speed control with end-effects compensation is derived. Finally, a new technique of LIM end-effects estimation is proposed based on the model reference adaptive system (MRAS) theory using the instantaneous active power and the estimated stator currents vector. These estimated currents are obtained through the solution of LIM state equations.

Simulations were carried out in MATLAB/SIMULINK to demonstrate the effectiveness and robustness of LIM speed control with the proposed MRAS inverse rotor time constant tuning to estimate end-effects value. The numerical validation results show that the proposed scheme permits the drive to achieve good dynamic performance, satisfactory for the estimated end-effects of the LIM model and robustness to uncertainties.

The end-effects causes a drop in the magnetizing, primary and the secondary inductance, requiring a more complex LIM control scheme. This paper presents a new approach of LIM end-effect estimation based on the online adaptation and tuning of the LIM inductances. The proposed scheme use the inverse rotor time constant tuning for end-effects correction in LIM vector control block.

The waste recycling industry increasingly relies on magnetic density separators. These devices generate an upward magnetic force in ferro-fluids allowing to separate the immersed particles according to their mass density. Recently, a new separator design has been proposed that significantly reduces the required amount of permanent magnet material. The purpose of this paper is to alleviate the undesired end-effects in this design by altering the shape of the ferromagnetic covers of the individual poles.

The paper represents the shape of the ferromagnetic pole covers with B-splines and defines a cost functional that measures the non-uniformity of the magnetic field in an area above the poles. The authors apply an iso-geometric shape optimization procedure, which allows us to accurately represent, analyze and optimize the geometry using only a few design variables. The design problem is regularized by imposing constraints that enforce the convexity of the pole cover shapes and is solved by a non-linear optimization procedure. The paper validates the implementation of the algorithm using a simplified variant of the design problem with a known analytical solution. The algorithm is subsequently applied to the problem posed.

The shape optimization attains its target and yields pole cover shapes that give rise to a magnetic field that is uniform over a larger domain.

This increased magnetic field uniformity is obtained at the cost of a pole cover shape that differs per pole. This limitation has negligible impact on the manufacturing of the separator. The new pole cover shapes therefore lead to improved performance of the density separation.

Due to the larger uniformity the generated field, these shapes should enable larger amounts of waste to be processed than the previous design.

This paper treats the shapes optimization of magnetic density separators systematically and presents new shapes for the ferromagnetic poles covers.

The purpose of this paper is to propose mover position control of linear induction motor (LIM) using an adaptive backstepping approach based on field orientation.

First, the indirect field‐oriented control LIM is derived. Then, an adaptive backstepping approach based on field‐oriented control of LIM is proposed to compensate the uncertainties which occur in the control. Mover position amplitude tracking objective is formulated, under the assumption of unknown total mass of the moving element, viscous friction, and load force, so that the position regulation is achieved.

The effectiveness and robustness of the proposed control scheme are verified by numerical simulation using Matlab/Simulink model. The numerical validation results of the proposed scheme have presented good transient control performances and robustness to uncertainties compared to the conventional backstepping control design.

The paper presents an adaptive backstepping approach for LIM control that achieves mover position amplitude tracking objective under mechanical parameter variation.

The purpose of this paper is to develop a combined control (CC) technique based on the direct torque control (DTC) strategy and vector control (VC) method, to improve the overall performance of a three-phase induction machine (TPIM) drives.

The proposed control scheme includes a table-based DTC strategy in connection with a proportional-integral-sliding mode controller and pulse width modulation switching strategy. The control system has merits of DTC technique such as simple structure, less dependent on machine parameters, fast dynamic response and merits of VC technique such as high accuracy and constant switching frequency.

To validate the effectiveness of the proposed control system, simulation and experimental studies are carried out for a 0.75 kW TPIM in different operating conditions. The achieved results show the superiority of the proposed method in terms of fast dynamics and simple structure compared to the VC strategy and low speed and torque ripples and constant switching frequency compared to the DTC method.

Compared to the conventional CC strategies, the control law of the proposed method is based on DTC theory and modulation is established based on VC. In other words, the variable switching frequency which is one of the main disadvantages of the conventional CC strategies is rectified using the proposed CC scheme.

This paper proposes a new framework for optimizing investment decisions when deciding about information security remedies.

The framework assumes that the organization is aware of a set of remedies that can be employed to address end‐effects that have been identified. The framework also assumes that the organization defines its information security policy by setting a minimum level of protection for each end‐effect. Given the two sets of costs, that of the end‐effect and the potential damage it can cause and that of the remedy and the required level of protection from each end‐effect, this framework can be used to identify the optimal set of remedies for a given budget that complies with the organization's information security policy. The framework is illustrated using a practical example concerning investment decision optimization in a financial organization.

The paper shows that exhausting the information security budget does not assure a higher level of security required by the organisation.

Concentrating on end‐effects and on the organizational requirements eases the process of remedy selection. The proposed methodology circumvents the common process of assuming probabilities of information security events.

This research proposes a practical and an easily implementable framework, enabling the information security manager to align the information security remedies and best practice methodological requirements with organizational budget constraints and business requirements while maintaining a required level of security.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

The purpose of this paper is to investigate and compare the influence of end-effect on the torque-speed characteristics of three conventional switched flux permanent magnet (SFPM) machines having different stator/rotor pole combinations, i.e. 12/10, 12/13 and 12/14 as well as three novel topologies with less permanent magnets (PMs), i.e. multi-tooth, E-core and C-core.

SFPM machines combine the advantages of simple and robust rotor and easy management of the temperature due to the location of the PMs and armature windings on the stator. However, due to spoke location of the PMs a large flux leakage in the end region, i.e. end-effect, can be observed which could result in a large reduction in the electromagnetic performance. Therefore, the influence of end-effect on the torque-speed characteristics is investigated. 3D-finite element analyses (FEA) results are compared with their 2D-FEA counterparts in order to account for the end-effect influence.

It has been concluded that due to end flux leakage, lower torque capability in the constant torque region is observed in the six machines. However, improved flux-weakening capability in the conventional machines can be exhibited at high current levels, whereas due to the large inductance lower power capability in the multi-tooth, E-core and C-core machines is obtained.

The influence of temperature rise on the performance is not included.

This paper has analysed the influence of end-effect on the torque-speed characteristics of several SFPM machines.

The purpose of this paper is to present an analysis of the force ripples of an open slot permanent magnet linear synchronous motor (PMLSM). A calculation procedure using 2D finite elements method (2D‐FEM) is then evaluated with experimentations.

First, the studied PMLSM and its main features are introduced. Then, the 2D‐FEM model used to study the motor is presented. The methods used to calculate the force and the meshing procedures are also highlighted. The calculated no‐load force is compared to measurements. Lastly, the validated model is used to study the influence of the current magnitude on the force ripples at load.

In addition to the no‐load case, the influence of the current magnitude on these forces is presented.

The paper is orientated with a sound industrial background. For that reason, the impact of the current saturation on the thrust generation is presented via the evolution of the thrust coefficient, which is the force to the RMS currents ratio.

The purpose of this paper is to present a calculation optimization method that is able to achieve the best induced power profile (and subsequent temperature distribution) in a disk or billet workpiece processed by induction heating.

A volume integral method, also known as the mutually coupled circuits method, is implemented in MatLab^® environment to solve axial‐symmetrical induction systems. It is completed with an optimization procedure based on Nelder‐Mead simplex algorithm, with the goal of obtaining a specified distribution of the induced power in the load. In this way, it is possible to predict current amplitudes for implementing the so‐called “zone controlled induction heating” (ZCIH) process.

Some examples of calculation results are given, both for disc and billet loads. By the excitation of the inductor coils with a set of currents of appropriate amplitude and phase values, it is possible to achieve an optimized profile of induced power distributions.

This paper validates a method to predict currents and phases in a load‐inductor ZCIH system, confirming the possibility of obtaining specified induced power density distributions, according to the process requirements, e.g. for compensation of the load edge‐effect.

To develop structured guidelines for the synthesis of dynamic force simulators that are required for the testing of high speed aerospace actuators. To provide realistic and proven solutions at both test bench hardware and control design levels.

The state of the art in control design applied to load simulators in mainly based on complex controllers and does not take into account practical considerations. The objective of the present work is to provide generic preliminary design rules to ensure that the test bench architectures (frame, power transmission and control) and the components specifications are consistent with the targeted performance. Once selected the appropriate power transmission architecture, a linear approach is used as a foundation to generate design rules. Then, preliminary design is achieved thanks to the introduction, as early as possible, of the unavoidable technological defects.

A step‐by‐step methodology allows the designer to select the controller architecture and to specify components with special care to their consistency with the required dynamic performance. The linear then practical approach generates key rules that can be used in the very early phase of the test bench design.

Practical considerations on the components static and dynamic limitations are introduced progressively to make the natural test bench performance as consistent as possible with the performance requirements. Consequently, the controller becomes simpler to design and robust.