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The purpose of this paper is to focus on various control strategies for permanent magnet synchronous generator (PMSG) systems, in order to stabilize the dc link output voltage over a wide operation speed range.

Two control methods, namely, the flux regulation control (FRC) which adjusts the stator flux linkage and then indirectly stabilize the dc link voltage, and the direct voltage control (DVC) which directly stabilize the dc link voltage by regulating the power angle, are proposed in this paper. Both methods can be realized by either approach of the conventional space vector pulse width modulation (SVPWM) or the proposed single voltage vector modulation (SVVM).

The FRC can optimize the field in the PMSG, however, the realization is complicated. The DVC need not estimate and regulate the stator flux linkage, hence is easy to implement. On the other hand, the SVPWM can provide smooth armature current and dc link voltage, while the SVVM applies only one voltage vector during each control cycle, hence, is simple to realize and requires the minimum switching on the PWM rectifier. All cross-combinations between the two control methods and the two realization approaches work well.

The proposed FRC and DVC methods are simpler than the conventional field oriented control, while the proposed SVVM is a novel and efficient approach to generate the PWM status. Optimal cross-combination, either of SVPWM-FRC, SVVM-FRC, SVPWM-DVC and SVVM-DVC, can be chosen to satisfy the system characters and requirements.

The aim of the paper is to conduct an analytical study of a new method of induction motor torque and flux direct control with nonlinear controllers.

The method is based on the inverter state predictive determination in order to minimize the torque and flux errors.

The proposed method allows one to eliminate known DTC disadvantages, i.e. the hexagonal flux shape and nonsinusoidal current at a low motor speed, and also secures a decrease of torque and flux pulsation.

This new method enables a more precise reproduction of the motor torque and flux command signals, working with the same sampling frequency of the control processor as in the case of the standard DTC method. The decreased torque pulsations cause a decrease of the motor speed pulsation.

An innovative optimal control method is presented. The correctness of the initial assumptions as well as the expected final results have been verified in practice.

The purpose of this paper is to analyze electromagnetic performance and develop an analytical approach to find the suitable coil combination and no-load flux linkage of the proposed hybrid excited consequent pole flux switching machine (HECPFSM) while minimizing the drive storage and computational time which is the main problem in finite element analysis (FEA) tools.

First, a new HECPFSM based on conventional consequent pole flux switching permanent machine (FSPM) is proposed, and lumped parameter magnetic network model (LPMNM) is developed for the initial analysis like coil combination and no-load flux linkage. In LPMNM, all the parts of one-third machine are modeled which helps in reduction of drive storage, computational complexity and computational time without affecting the accuracy. Second, self and mutual inductance are calculated in the stator, and dq-axis inductance is calculated using park transformation in the rotor of the proposed machine. Furthermore, on-load performance analysis, like average torque, torque density and efficiency, is done by FEA.

The developed LPMNM is validated by FEA via JMAG v. 19.1. The results obtained show good agreement with an accuracy of 96.89%.

The proposed HECPFSM is developed for high-speed brushless AC applications like electric vehicle (EV)/hybrid electric vehicle (HEV).

The proposed HECPFSM offers better flux regulation capability with enhanced electromagnetic performance as compared to conventional consequent pole FSPM. Moreover, the developed LPMNM reduces drive storage and computational time by modeling one-third of the machine.

The purpose of this paper is to estimate that the start-up current parameters are stochastic or not. Electronic equipment in luminaries significantly improves their luminous efficiency, thereby increasing the energy efficiency of lighting installations. However, the use of electronics [e.g. electronic ballasts for discharge lamps or power supply units for light-emitting diode (LED) luminaries] may also cause some negative effects in lighting installations. One of such effects is large inrush current, which can greatly exceed the admissible line load and trigger the overcurrent protective devices.

The paper presents results of laboratory tests together with their statistical analysis of the inrush currents of lighting luminaires. Three road luminaires build in different technologies of similar power have been selected for the study. The theoretical distributions described by the analytical formulas matched the empirical distributions by using the MATLAB’ Statistical Toolbox.

As parameters that characterize short-time overcurrent at start-up are the maximum value of overcurrent amplitude in start-up moment (I_PIC), the duration of overcurrent in start-up moment (t_PIC) and melting integral MI. The aim of this statistical analysis of the selected parameter is to provide an overcurrent mathematical description allowing to estimate the probability of occurrence of values. For lighting luminaire fitted with magnetic ballasts, the parameters analyzed will randomly vary with the moment of power on. For electronic ballasts, the occurrence of this phenomenon depends on the adopted construction solution.

This will allow, for example, to estimate the probability of activation of protection device by comparing the value of the inrush current Joule’s integral MI with its value for the analyzed protection device. The proposed method may be useful for checking the selectivity of the protection devices in the lighting system.

The study enables application of a probabilistic model for analysis of inrush currents of lighting luminaire and predicting the possible consequences of their occurrence.

The direct torque control (DTC) of induction motor (IM) drive is featured by high ripples in the electromagnetic torque and stator flux profiles because they are controlled by two hysteresis regulators. Furthermore, the machine flux is not directly measurable. Hence, it is better to reconstitute it from the instantaneous electrical equations of the machine. Once the stator flux is estimated, we can guarantee a reliable sensorless DTC control. Thus, the purpose of this research work is to ensure fast response and full reference tracking of the IM under sensorless DTC strategy with desired dynamic behavior and low ripple levels.

In this work, an improved DTC strategy, which is DTC_SVM_3L, is suggested. The first step of the designed approach is to substitute the conventional inverter feeding the motor with a three-level inverter because it guarantees reduced switching losses, improved quality of voltage waveform and low-current total harmonic distortion rate. The second aim of this paper is to make the IM operate at a constant switching frequency by using the nearest three vectors-based space vector modulation (SVM) technique rather than hysteresis controllers. The third objective of this study is to conceive a sliding-mode stator flux observer, which can improve the control performances by using a sensorless algorithm to get an accurate estimation, and consequently, increase the reliability of the system and decrease the cost of using sensors. The stability of the proposed observer is demonstrated based on the Lyapunov theory. To overcome the load change disturbance in the proposed DTC control strategy, this paper exhibits a comparative assessment of four speed regulation methods: classical proportional and integral (PI) regulator, fuzzy logic PI controller, particle swarm optimization PI controller and backstepping regulator. The entire control algorithm was tested under different disturbances such as stator resistance and load torque variations.

It was ascertained that the IM, controlled with three-level inverter, exhibits good performances under the proposed DTC-SVM strategy based on a sliding-mode observer. The robustness of the suggested approach against parameter variations is also proved.

The theoretical development of the proposed control strategy is thoroughly described. Then, simulations using Matlab/Simulink software are launched to investigate the merits of the sensorless DTC-SVM command of three-level inverter-fed IM drive with different speed regulators.

The worldwide production and the consumption of CFCs are now controlled through the Montreal Protocol. A meeting in London in June 1990 of the signatories of the Protocol will almost certainly tighten the controls on CFCs and introduce regulations to control other common chlorinated solvents. This paper gives the reasons why worldwide control of emissions of chlorinated substances is necessary, the events that led up to the present controls and the prognosis for future regulations. The properties and uses of the six key chlorinated solvents are discussed. Each industrial solvent‐using sector has a range of options available to implement cutbacks and eventual elimination of chlorinated solvents.

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 the control method proposed in this paper is to address the problem of the poor anti-interference of the suspension winding current in the traditional bearingless induction motor (BL-IM) direct suspension force control process.

A model predictive direct suspension force control of a BL-IM based on sliding mode observer is proposed in this paper. The model predictive control (MPC) is introduced to the traditional direct suspension force control to improve the anti-interference of the suspension current. A sliding mode flux linkage observer is designed and applied to the MPC system, which reduces the error of the parameter observation and improves the robustness of the system. The strategy is designed and implemented in the MATLAB/Simulink and the two-level AC speed regulation platform.

The simulation and experimental results show that the performance of the BL-IM under the control method proposed in this paper is better than that under the traditional direct suspension force control, and the suspension performance of the motor and the anti-interference of the control system are improved.

This study helps to improve the suspension performance of the motor and the anti-interference of the control system.

The lengthy review of the Food Standards Committee of this, agreed by all public analysts and enforcement officers, as the most complicated and difficult of food groups subject to detailed legislative control, is at last complete and the Committee's findings set out in their Report. When in 1975 they were requested to investigate the workings of the legislation, the problems of control were already apparent and getting worse. The triology of Regulations of 1967 seemed comprehensive at the time, perhaps as we ventured to suggest a little too comprehensive for a rational system of control for arguments on meat contents of different products, descriptions and interpretation generally quickly appeared. The system, for all its detail, provided too many loopholes through which manufacturers drove the proverbial “carriage and pair”. As meat products have increased in range and the constantly rising price of meat, the “major ingredient”, the number of samples taken for analysis has risen and now usually constitutes about one‐quarter of the total for the year, with sausages, prepared meats (pies, pasties), and most recently, minced meat predominating. Just as serial sampling and analysis of sausages before the 1967 Regulations were pleaded in courts to establish usage in the matter of meat content, so with minced meat the same methods are being used to establish a maximum fat content usage. What concerns food law enforcement agencies is that despite the years that the standards imposed by the 1967 Regulations have been in force, the number of infringements show no sign of reduction. This should not really surprise us; there are even longer periods of failures to comply; eg., in the use of preservatives which have been controlled since 1925! What a number of public analysts have christened the “beefburger saga” took its rise post‐1967 and shows every indication of continuing into the distant future. Manufacturers appear to be trying numerous ploys to reduce the content below the Regulation 80% mainly by giving their products new names. Each year, public analysts report a flux of new names and ingenious defences; eg, “caterburgers” and similar concocted nomenclature, and the defence that because the name does not incorporate a meat, it is outside the statutory standard.

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.