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The purpose of this paper is to integrate the function of a speed controller for induction motor (IM) drive, such as the speed PI controller, the current vector controller, the slip speed estimator, the space vector pulse width modulation scheme, the quadrature encoder pulse, and analog to digital converter interface circuit, etc. into one field programmable gate array (FPGA).

First, the mathematical modeling of an IM drive, the field-oriented control algorithm, and PI controller are derived. Second, the very high speed IC hardware description language (VHDL) is adopted to describe the behavior of the algorithms above. Third, based on electronic design automation simulator link, a co-simulation work constructed by ModelSim and Simulink is applied to verify the proposed VHDL code for the speed controller intellectual properties (IP). Finally, the developed VHDL code will be downloaded to the FPGA for further control the IM drive.

In realization aspect, it only needs 5,590 LEs, 196,608 RAM bits, and 14 embedded 9-bit multipliers in FPGA to build up a speed control IP. In computational power aspect, the operation time to complete the computation of the PI controller, the slip speed estimator, the current vector controller are only 0.28 μs, 0.72 μs, and 0.96 μs, respectively.

Fast computation in FPGA can speed up the speed response of IM drive system to increase the running performance.

This is the first time to realize all the function of a speed controller for IM drive within one FPGA.

The purpose of this paper is to analyze the impact of magnetic saturation on the steady‐state operation of the induction motor (IM) drive in regard to rotor field‐oriented control (RFOC). The aim of the presented two methods is to obtain the required steady‐state torque with minimal stator current, which thus reduces stator coper losses considerably.

The first method is based on an analytic calculation of the peak torque‐per‐ampere ratio curve of saturated IM. The torque characteristics obtained at a constant stator current are used to calculate that value of magnetizing current which gives the minimal stator current for the required load torque. The second method directly searches the minimal stator current for the required load torque. Experiments completely confirm the efficiency of the proposed selection of a magnetizing current reference.

Operation of the IM drive strongly depends on a proper selection of the rotor flux linkage reference value, the selection of which represents an additional degree of freedom in control design. Therefore, it can be used to optimize some of those drive features subjected to voltage and current constraints. The proposed calculation procedure is simple so that can be easily implemented in practically application. However, some additional IM data like magnetizing curve, inertia moment, and coefficient of viscous friction are necessary.

The substantial impact of saturation on the stead‐state torque characteristics of IM, determined for the constant stator current and the constant d‐axis stator current, is determined analytically and numerically.

The role played by the marketing function (MF) has been subjected to considerable academic and public media attention. Recent research reflects an ongoing debate on MF's decreasing influence attributed by some to its poor performance. However, studies have analyzed the general marketing (GM) function and domestic operations and remained silent on international marketing's (IM) influence and its impact on firms’ international operations and performance as another aspect of marketing's influence. This lacuna is unfortunate, given that internationalization is crucial to many firms in today's globalizing world. The purpose of this paper is to examine the interactions between IM and GM functions as determinants of IM's influence.

The study extends previous models to the international context, utilizes an inclusive set of strategic international orientations as consequences and mediators of IM's influence, and assesses possible synergy between orientations.

IM functions are influential, valuable, and play an important role. IM-GM coordination enhances IMs’ influence while IM-GM conflicts and IM's influence are unrelated. IMs’ influence enhances performance directly and indirectly through orientations. Importantly, the combined orientations had a negative synergistic effect on performance.

International marketers and top management should consider tactics to increase IMs’ influence and thus benefit their firms.

The study is the first to recognize and empirically focus on the relationships between IM and GM as distinct functions. The study accounts for a combined impact of international orientations on international performance.

The purpose of this paper is to present a complete solution for speed sensorless AC drive with voltage source inverter, induction machine, and motor choke. Major problems with adjustable speed drives are underlined and the use of motor choke is justified. An AC drive with motor choke can work only if specific modifications in the control algorithms are done.

The goal of the paper is to present new nonlinear vector control method for induction motor drive. In the control system, the presence of motor choke is taken into account. The choke changes the structure of the predictive controller and state observer. The new concept of integrating the predictive controller with electromagnetic forces observer is presented. The paper presents theoretical description of the system as well the simulation and experimental verification.

The paper shows that the suggested decoupled AC drive control system is operating better than a system without decoupling. The system with motor choke requires modifications in the current controller and observer system. With omitting the motor choke a speed sensorless drive cannot work properly.

The solution is oriented for industrial applications because in numerous industrial dives the motor choke is utilized. However, with motor choke many sophisticated control algorithms cannot work properly. The concept presented in the paper solves such practical problems.

The paper presents a completely new decoupled field‐oriented control system with load angle controller, predictive current controller and state observer for AC drive with motor choke.

The purpose of this paper aims to design a robust wind turbine emulator (WTE) based on a three-phase induction motor (3PIM).

The 3PIM is driven by a soft voltage source inverter (VSI) controlled by a specific space vector modulation. By adjusting the appropriate vector sequence selection, the desired VSI output voltage allows a real wind turbine speed emulation in the laboratory, taking into account the wind profile, static and dynamic behaviors and parametric variations for theoretical and then experimental analysis. A Mexican hat profile and a sinusoidal profile are therefore used as the wind speed system input to highlight the electrical, mechanical and electromagnetic system response.

The simulation results, based on relative error data, show that the proposed reactive power control method effectively estimates the flux and the rotor time constant, thus ensuring an accurate trajectory tracking of the wind speed for the wind emulation application.

The proposed architecture achieves its results through the use of mathematical theory and WTE topology combine with an online adaptive estimator and Lyapunov stability adaptation control methods. These approaches are particularly relevant for low-cost or low-power alternative current (AC) motor drives in the field of renewable energy emulation. It has the advantage of eliminating the need for expensive and unreliable position transducers, thereby increasing the emulator drive life. A comparative analysis was also carried out to highlight the online adaptive estimator fast response time and accuracy.

The main purpose of this paper is to evaluate the two energy saving position control strategies for AC drives valid for a wide range of boundary conditions including an analysis of their energy expenses.

For energy demands analysis, the optimal energy control based on mechanical and electrical losses minimization is compared with the near-optimal one based on symmetrical trapezoidal speed profile. Both control strategies respect prescribed maneuver time and define acceleration profile for preplanned rest-to-rest maneuver.

Presented simulations confirm lower total energy expenditures of energy optimal control if compared with near-optimal one, but the differences are only small due to the fact that two energy saving strategies are compared.

Developed overall control system consisting of energy saving profile generator, pre-compensator and position control system respecting principles of field-oriented control is capable to track precomputed state variables precisely.

Energy demands of both control strategies are verified and compared to simulations and preliminary experiments. The possibilities of energy savings were confirmed for both control strategies.

Experimental verification of designed control structure is sufficiently promising and confirmed assumed energy savings.

This paper aims to present the findings from research that sought to evaluate the construction industry's approach to information management at the project level and to review the operation of an information management systems (IMS) on selected projects.

Data from three IMS used on three separate construction projects were extracted over a four‐year period as the life of the construction stage of each project came to an end. Three distinct databases of the IMS were analysed and document statistics were extracted to demonstrate the level of activity within the construction project, and between members of the construction team, using a simple counting technique for each document type.

The paper finds that major construction projects generate, process and store considerable quantities of real‐time information prior to, during, and post on‐site construction. The construction activities are shrouded in information and management of the construction project requires appropriate systems which facilitate bi‐directional data input, information processing, dissemination and functional access. Historically, the onus of storing, disseminating and managing project information has fallen to each of the individual project team members of the many organisations involved within the project. Hardware advances, coupled with improved electronic and paper‐based IMS facilitate synergistic standardised filing and information control, which reduces the reliance on each individual or organisation to undertake the task of storing and controlling information. An IMS also has the capability to engage with performance management and reporting systems which aid not only management of the project, but also management of the organisation.

Case reviews show that in today's complex construction environment the use of an appropriate IMS has the potential to bring about team syntegrity and engender increased collaboration and integration among project members. The findings from completed projects exemplify a number of benefits to be accrued from adoption of an IMS and the resultant change in operating culture. Crucially, however, the pitfalls of such IMS systems are also identified.

The findings provide new knowledge about the management of information from construction projects.

This paper aims to explore the types of learning engendered by internal mobility (IM) by referring to the principles elaborated by Bateson (1972).

A qualitative methodology is followed with interviews among 50 professionals working at four large French firms.

A system of classification for IM is proposed, namely, replication, adaptation, innovation and revolution.

The identification of these categories invites human resource managers to reconsider the traditional career paths.

This paper brings a new perspective on the possible link between learning and IM and questions what employees really learn thanks to their moves.

This paper aims to propose an improved direct torque control (DTC) for the induction motor’s performance enhancement using dual nonlinear techniques. The exact feedback linearization is implemented to create a linear decoupled control. Besides, the fuzzy logic control approach has been inserted to generate the auxiliary control input for the feedback linearization controller.

To improve the DTC for induction motor drive, this work suggests the incorporation of two nonlinear approaches. As the classical feedback linearization suffers while the presence of uncertainties and modeling inaccuracy, it is recommended to be associated to another robust control approach to compensate the uncertainties of the model and make a robust control versus the variations of the machine parameters. Therefore, fuzzy logic controllers will be integrated as auxiliary inputs to the feedback linearization control law.

The simulation and the experimental validation of the proposed control algorithm show that the association of dual techniques can effectively achieve high dynamic behavior and improve the robustness against parameters variation and external disturbances. Moreover, the space vector modulation is used to preserve a fixed switching frequency, reduce ripples and low switching losses.

The theoretical, simulation and experimental studies prove that the proposed control algorithm can be used on different AC machines for variable speed drive applications such as oil drilling, traction systems and wind energy conversion systems.

The proposed DTC strategy has been developed theoretically and realized through simulation and experimental implementation. Different operation conditions have been conducted to check the ability and robustness of the control strategy, such as steady state, speed reversal maneuver, low-speed operation and parameters variation test with load application.

The purpose of this paper is to deal the adaptation of a direct torque control (DTC) strategy, originally dedicated to three level three leg inverter fed induction motor (IM) drives, following a leg failure that required the reconfiguration of the inverter from three to two legs.

In case of troubles with one leg of a three level inverter, it is interesting in some applications to keep operating using the two remaining legs. So, after the detection and isolation of the faulty leg, the drive connection should be rearranged with the connection of the motor phase, previously linked to the faulty leg, to the mid point of the DC-bus voltage, leading to a three level two leg inverter topology (also called bridge B8-inverter).

It has been found that the IM drive exhibits better performances under the proposed DTC strategy dedicated to the reconfigured inverter than those yielded by the DTC of the IM drive under healthy operation of the inverter. It has been noticed that the only drawback affecting the reconfigured inverter fed IM drive is the speed range limitation.

This work should be extended by an experimental validation of the proposed DTC strategies.

The power factor of the reconfigured three level inverter fed IM drive is higher than the one yielded by the three level three leg inverter fed one. This represents a crucial cost benefit.