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Power sharing among multiterminal high voltage direct current terminals (MT-HVDC) is mainly developed based on a priority or sequential manners, which uses to prevent the problem of overloading due to a predefined controller coefficient. Furthermore, fixed power sharing control also suffers from an inability to identify power availability at a rectification station. There is a need for a controller that ensures an efficient power sharing among the MT-HVDC terminals, prevents the possibility of overloading, and utilizes the available power sharing. A new adaptive wireless control for active power sharing among multiterminal (MT-HVDC) systems, including power availability and power management policy, is proposed in this paper. The proposed control strategy solves these issues and, this proposed controller strategy is a generic method that can be applied for unlimited number of converter stations. The rational of this proposed controller is to increase the system reliability by avoiding the necessity of fast communication links. The test system in this paper consists of four converter stations based on three phase-two AC voltage levels. The proposed control strategy for a multiterminal HVDC system is conducted in the power systems computer aided design/electromagnetic transient design and control (PSCAD/EMTDC) simulation environment. The simulation results significantly show the flexibility and usefulness of the proposed power sharing control provided by the new adaptive wireless method. [ABSTRACT FROM AUTHOR]

Software-defined networking (SDN) is widely used in multiple types of data center networks, and these distributed data center networks can be integrated into a multi-domain SDN by utilizing multiple controllers. However, the network topology of each control domain of SDN will affect the performance of the multidomain network, so performance evaluation is required before the deployment of the multi-domain SDN. Besides, there is a high cost to build real multi-domain SDN networks with different topologies, so it is necessary to use simulation testing methods to evaluate the topological performance of the multi-domain SDN network. As there is a lack of existing methods to construct a multi-domain SDN simulation network for the tool to evaluate the topological performance automatically, this paper proposes an automated multi-domain SDN topology performance evaluation framework, which supports multiple types of SDN network topologies in cooperating to construct a multi-domain SDN network. The framework integrates existing single-domain SDN simulation tools with network performance testing tools to realize automated performance evaluation of multidomain SDN network topologies. We designed and implemented a Mininet-based simulation tool that can connect multiple controllers and run user-specified topologies in multiple SDN control domains to build and test multi-domain SDN networks faster. Then, we used the tool to perform performance tests on various data center network topologies in single-domain and multi-domain SDN simulation environments. Test results show that Space Shuffle has the most stable performance in a single-domain environment, and Fat-tree has the best performance in a multi-domain environment. Also, this tool has the characteristics of simplicity and stability, which can meet the needs of multi-domain SDN topology performance evaluation. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract PID controllers are still widely practiced in the industrial systems. In the literature, many publications can be found considering PID controller design for unstable processes. However, owing to the structural limitations of PID controllers, generally, good closed loop performance cannot be achieved with a PID for controlling unstable processes and usually a step response with a high overshoot and oscillation is obtained. On the other hand, PI–PD controllers are proved to give very satisfactory closed loop performances for unstable processes. The paper presents a simple design method to tune parameters of a PI–PD controller for the control of the unstable processes with time delay. The proposed method is based on plotting the stability boundary locus, which is a locus dependent on the parameters of the controller and frequency, in the parameter plane. The method uses a new concept named centroid of the convex stability region. Simulation examples and an experimental application are given to illustrate the superiority of the proposed method over some existing ones. Highlights • The paper represents a novel method for PI–PD control of the unstable systems. • The proposed method uses a new concept named centroid of convex stability region. • Ability of being extended to uncertain plants of the proposed method by means of Kharitonov theorem is an important advantage. [ABSTRACT FROM AUTHOR]

The proportional-integral-derivative (PID) controllers have experienced series of structural modifications and improvements. Example of such modifications are set-point weighting and fractional ordering. While the former is to achieve two-degree-of-freedom (2DOF) ability of set-point tracking and disturbance rejection, the latter is to ensure smooth control action. Therefore, this paper reviews various forms of PID controllers and provides a comparative analysis of 2DOF PID and 2DOF fractional order PID (FOPID) controllers. The paper also discusses the conversion of one PID form to another. For the comparative analysis of the various controllers, a class of unstable systems are considered. Simulation result shows that in most cases the conversion from one form to another does not significantly affect the performance of the system. It is also observed that the 2DOF controllers (2DOF PID and 2DOF FOPID) improved significantly the performance of the ordinary PID controllers. [ABSTRACT FROM AUTHOR]

This paper proposes a Cascaded PIDA (Proportional-Integral-Derivative-Acceleration) load frequency controller (LFC) for interconnected power systems with Wave Energy Conversion Systems (WECS). The proposed controller parameters are optimized using the Marine Predator Algorithm (MPA), which is a recent optimization technique known to be robust. The Cascaded PIDA controller results are compared to the results of a single structure MPA based PIDA controller and other PIDA controllers whose parameters are optimized using various optimization techniques presented in previous literature. Results show that the MPA-based PIDA-LFC has better results than other PIDA controllers optimized by other techniques, while the MPA-Cascaded PIDA-LFC has proven to have the best performance where the frequency and the tie-line power fluctuations, due to the connected Wave Energy Conversion System, are efficiently damped. Moreover, the results are presented in the form of time-domain simulation conducted via MATLAB /SIMULINK. [ABSTRACT FROM AUTHOR]

In this paper we represent a decentralised LTI control system with decentralised fixed modes (DFMs) by a weighted directed graph and derive sufficient conditions for it to be stabilisable. The sufficient conditions relate to whether the DFMs are decentralised quotient fixed modes (QFMs); decentralised QFMs cannot be shifted by any type of decentralised controller. We use a graph theoretic approach, using existing concepts, and introducing some new ones, to identify the decentralised QFMs for the class of LTI systems that have distinct, repeated, cyclic, or non-cyclic DFMs. It is shown in this paper that a DFM is a QFM, and thus cannot be moved, when some identifiable graphical properties exist. The main results are presented in terms of a Theorem with a constructive proof. Numerical examples are given to illustrate all aspects of the paper. [ABSTRACT FROM AUTHOR]

The paper considers recent trends in the development of electrically operated hydraulic drive. The main requirements to the dynamic characteristics of variable axial piston pumps with electric control and the need for search of ways of their improvement are specified. The investigation results show the dynamic characteristics of the process to control electro-hydraulic axial piston pump capacity at different parameters of pulse width modulation (PWM) signal. The regularity between PWM-signal frequency and the time of establishing the proper pump displacement was found. The paper stresses the need for more detailed study of this fact and its usage for the optimization of variable pump regulation speed in order to be applied in electro-hydraulic flow control systems. [ABSTRACT FROM AUTHOR]

This paper deals with the Newton-Raphson load flow solution for a power system with embedded UPFC, when this device is modeled with the use of so-called Voltage Source Model. The aim of the paper is to present results of the original investigation of the mentioned load flow solution from the numerical point of view. The carried out investigation give the base for the statement that performing the load flow computations in the rectangular coordinate system is much more beneficial than in the polar coordinate system, which is most often used in the existing papers. [ABSTRACT FROM AUTHOR]

In this paper, the considered hybrid power system (HPS) is having a wind turbine generator, a diesel engine generator (DEG) and a storage device (such as capacitive energy storage). This paper presents a comparative study of frequency and power control for the studied isolated wind–diesel HPS with four different classical controllers for the pitch control of wind turbines and the speed governor control of DEG The classical controllers considered are integral, proportional-integral, integral-derivative and proportional-integral-derivative (PID) controller. A quasi-oppositional harmony search (QOHS) algorithm is proposed for the tuning of the controller gains. The comparative dynamic simulation response results indicate that better performance may be achieved with choosing PID controller among the considered classical controllers, when subjected to different perturbation. Stability and sensitivity analysis, presented in this paper, reveals that the optimized PID controller gains offered by the proposed QOHS algorithm are quite robust and need not be reset for wide changes in system perturbations. [ABSTRACT FROM AUTHOR]

This paper investigates the performance of modular dc–dc forward converter in Input Parallel Output Series (IPOS) configuration which is controlled by an effective controller. This IPOS topology facilitates the converter to have high output voltage gain. The role of controller is crucial in ensuring the power sharing between the converters. Fuzzy controller, known for its versatility, is employed in this research work. The fuzzy controller feeds appropriate pulse width modulated control signals for appropriate input and load regulation. The performance of the fuzzy controller is analyzed by comparing it with proportional integral controller and a advanced neural network controller. The proposed IPOS system has been analyzed using MATLAB/Simulink environment and hardware prototype. The simulation and hardware results reveal that the suggested topology with fuzzy controller is very effective compared to its counterparts. [ABSTRACT FROM AUTHOR]

Highlights • The classification of appliances based on energy consumption pattern. • An energy management controller for demand side management. • Fuzzy logic and heuristic optimization techniques are used to reduce cost, energy consumption and PAR. • Fuzzy logic is used to control the throttleable and interruptible appliances. • Heuristic optimization algorithms are employed for scheduling of shiftable appliances. • Simulation results show a significant reduction in energy consumption, cost and PAR. Abstract The integration of information and communication technologies in traditional grid brings about a smart grid. Energy management plays a vital role in maintaining the sustainability and reliability of a smart grid which in turn helps to prevent blackouts. Energy management at consumer's side is a complex task, it requires efficient scheduling of appliances with minimum delay to reduce peak-to-average ratio (PAR) and energy consumption cost. In this paper, the classification of appliances is introduced based on their energy consumption pattern. An energy management controller is developed for demand side management. We have used fuzzy logic and heuristic optimization techniques for cost, energy consumption and PAR reduction. Fuzzy logic is used to control the throttleable and interruptible appliances. On the other hand, the heuristic optimization algorithms, BAT inspired and flower pollination, are employed for scheduling of shiftable appliances. We have also proposed a hybrid optimization algorithm for the scheduling of home appliances, named as hybrid BAT pollination optimization algorithm. Simulation results show a significant reduction in energy consumption, cost and PAR. [ABSTRACT FROM AUTHOR]

This paper proposes a novel approach for the implementation of limit controllers used for stall prevention and rotation speed limitation of a single-spool jet engine. In this approach, the protection requirements regarding the rotation speed are achieved through the use of a filter applied to the reference that will be sent to the power management controller of a Min-Max structure controller. The main controller variable is the turbine's core rotation speed. The filter chooses the most appropriate reference value aiming at respecting the engine established limits, such as the stall margin and the maximum rotation speed, during transient and steady-state behaviors. The Min-Max compensators structure chosen for the implementation of the controllers is proportional-integral with Back Calculation as the anti-windup technique. Simulation model of a GE-J85-13 single-spool jet engine has been used to test the new approach and compare it to the more common Min-Max structure, where each controller is implemented individually. The simulation contemplates the case where a step function is applied to the power management controller, where the final value is the maximum allowed rotation speed value, at sea-level, static and standard-day temperature conditions. The simulation is repeated for different values of Back Calculation gains using both Min-Max structures, and the behavior of the GE-J85-13 engine is evaluated in each case for comparison proposes. [ABSTRACT FROM AUTHOR]

Abstract This paper focuses on the integrated fault detection and control design (IFDCD) problem for continuous-time switched systems under asynchronous switching. Main goal is to design an observer by using piecewise Lyapunov function, H ∞ control technique and average dwell time approach. In addition, switched controllers are designed such that the closed-loop switched system is asymptotically stable. The designed controller/detector are assumed to be asynchronous with the original systems. The admissible solution of the IFDCD problem is obtained by solving linear matrix inequalities (LMIs). Finally, to illustrate the applicability and the effectiveness of the proposed method, a solution is designed for two different case studies of boost converter and highly maneuverable aircraft technology. Highlights • Switched system affected by additive actuator fault and sensor fault. switch asynchronously with the switching of the controller/detector. • The gains of the controller/detector are calculated by LMIs. • Based on piecewise-Lyapunov function and average dwell strict LMIs are constructed in a single-step. • By using a regulating parameter and by integrating all variables in one augmented matrix the conservatism is reduced. [ABSTRACT FROM AUTHOR]

Abstract This paper presents a new tuning method for fractional-order (FO)PID controllers to simplify current tuning and make FOPID controllers more convenient for industry, i.e. facilitate transition from state-of-art to state-of-use. The number of tuning parameters is reduced from five to three based on popular specification settings for PID controllers without the need for reduced process models which introduce modeling errors. A test batch of 133 simulated processes and two real-life processes are used to test the presented method. A comparative study between the new method and the established CRONE controller, quantifies the performance. The conclusion states that the new method gives fractional controllers with similar performances as the current methods but with a significantly decreased tuning complexity making FOPID controllers more acceptable to industry. Highlights • A simplified tuning method for FOPID is proposed. • The amount of tuning parameters for FOPID controllers is reduced from 5 to 3. • The performance of the resulting controllers is comparable to the CRONE controller. • Reduced tuning complexity makes FOPID more acceptable to industry. [ABSTRACT FROM AUTHOR]

Abstract The prime objective of this paper is to design and develop simple and efficient closed loop controllers independently for each of the conversion stages of a Modular Solid State Transformer (MSST) for low/medium voltage applications. The controller design is based on small signal averaged transfer function model using topology independent black box approach. Hence it can be universally adopted for any choice of topologies. The independently designed controllers enhance the modularity of the apparatus such that extension and reduction of ac/dc voltage and power levels are possible by addition and removal of modules as and when required. This paves way for easy maintenance and replacement of modules. Further, the cost and complexity in control is reduced to enable large scale market penetration of the apparatus. Time and frequency response plots are illustrated to validate the performance of the individual converters with the designed closed loop controllers. The simple control design adopted for MSST is shown to mitigate power quality issues to a greater extent possible. Simulation and experimental results are presented which substantiate the appropriateness of the small signal model and hence the controllers designed for the MSST. Graphical abstract Highlights • Transfer function model based on small signal averaging technique is proposed for the individual stages of Modular Solid State Transformer. • The transfer function model is topology- independent and hence universal. • The controller design based on the developed model is validated through simulation as well as laboratory prototype. • The proposed controller is simple and cost-effective thereby supporting easy market penetration. [ABSTRACT FROM AUTHOR]

This study proposes the air conditioner (AC) control system based on users' sensations. The purpose of the system is to improve low-performance ACs in terms of energy efficiency and comfortableness performance. The system consists of wireless sensor nodes and user nodes such as PCs and smartphones, and it is applicable to already installed ACs. The users enter their sensation such as cold, good, a little hot and very hot through the user node, and the system determines the appropriate control according to the users' sensations. The control signal is transmitted via an equipped IR remote controller. The appropriate control policy is determined based on Q-Learning, which is a reinforcement learning method. In this study, we propose several types of methods and investigate effective methods in terms of energy efficiency and comfortableness performance. For multiple users, several methods for integrating users' sensations are presented. These make our proposed system applicable to a large number of users. Further, in order to reduce the energy consumption and the number of users' inputs, several types of reward functions are presented. In addition to the reward functions proposed in [8], in this paper, we propose a new reward function, which improves the performance for the large number of users. In the simulation, five types of methods including a new proposal in this paper, are evaluated in terms of the time needed for providing a comfortable environment and the energy consumption. We clarify the effective methods among them and the tendency of the scalability against the number of users. [ABSTRACT FROM AUTHOR]

With innovation and aesthetics playing leading roles, the landscape of footbridge design continues to evolve towards lightweight, landmark structures, increasing the emphasis on mitigating lively dynamic responses. To satisfy architectural constraints, auxiliary control devices are being used to control the response under infrequent peak-loading events. Nearly all implemented control devices are permanent installations of passive systems, such as viscous dampers or tuned mass dampers (TMDs), that are tuned to a particular structural property and hence specific to the particular application. Recently, the concept of deployable, autonomous control systems has been presented, in which a robotic platform is combined with an active control device to yield a system that is capable of providing short-term control for a range of structures. This concept is particularly attractive in relation to footbridge applications, where the systems can be deployed during predictable peak-loading events such as marathons or used with temporary footbridges where the need for control depends on the intended use. In this paper, analytical modeling of a prototype system is presented to validate experimental identification. Furthermore, the role of the control-structure interaction (CSI) is described and compensated for through an active controller formulation and the use of a position feedback controller for disturbance rejection. The performance of the prototype system is evaluated experimentally and assessed relative to an equivalent passive TMD device. The experimental study validates the controller formulation and demonstrates the effectiveness of the prototype system. [ABSTRACT FROM AUTHOR]

Abstract This paper presents Modified Active Disturbance Rejection Control (MADRC) scheme and a systematic procedure to tune its tuning variables via. observer and controller gains. The problem of tuning is formulated as a constrained multi-objective optimization problem. Depending upon the application appropriate objective functions are chosen, and a unified objective is developed based on weighted sum approach. Five different weight combinations are considered, which result in five objective functions. Each objective function is individually optimized using Teaching-Learning Based Optimization (TLBO), this leads to five sets of tuning variables. Best among five alternatives will be selected based on Analytical Hierarchy Process (AHP). The effectiveness of this approach is validated through its application to a power system with load frequency control problems. Different simulation examples involving single-area and multi-area power systems are considered in the presence of sudden load disturbances, model uncertainties, and parameter variations. Further stability analyses are carried out in a standard two-degree of freedom Internal Model Control (IMC) framework. Highlights • Design of MADRC involving model assisted ESO and state feedback control law. • New tuning procedure for obtaining optimal parameters ω0 and ωc for fast estimation and improved performance. • Efficacy of the proposed method is validated through its application on single area and multi-area power system models. • Stability analysis of the proposed scheme is carried out in a standard two-degree of freedom Internal Model Control scheme. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to control the trajectory of the nonlinear missile model in the pitch channel by using Fractional PID controller (FPID) and Gain Schedule Fractional PID controller (GSFPID). FPID and GSFPID with nonlinear missile model are designed where their parameters are tuned by Simulink design optimization in the Matlab toolbox. This optimization method gives the optimal parameters that achieve the best tracking with step unit reference signal. The GSFPID controller compensates the restrictions that represent physical limits of actuators in the pitch channel. The GSFPID with nonlinear missile model is designed in two phases. The first phase is the boost phase where the thrust force is maximized and the second phase is sustain phase where the thrust force is minimized. The equations of motion for nonlinear missile model with FPID and GSFPID are modelled mathematically in the Matlab-Simulink environment. The results of FPID and GSFPID controllers with the nonlinear missile model are presented and compared. The wind effect and the dynamic uncertainties effects are researched and the results are compared. The closed-loop nonlinear system is linearized by the Simulink linear analysis tool at critical operating point t = 5.8 sec and the stability is studied. [ABSTRACT FROM AUTHOR]

In demand side management (DSM), scheduling of appliances based on consumer-defined priorities is an important task performed by a home energy management controller (HEMC). This paper presents a DSM technique that is capable of controlling loads within a smart home considering time-varying appliances’ priorities. An evolutionary accretive comfort algorithm (EACA) is developed based on four postulations that allow time-varying priorities to be quantified in time and device-based features. Based on the input data considering the appliances’ power ratings, its time of use, and absolute comfort derived from priorities, the EACA is able to generate an optimal energy consumption pattern which would give maximum satisfaction at a predetermined user budget. A cost per unit comfort index ( χ ) which relates the consumer expenditure to the achievable comfort is also demonstrated. To test the applicability of the proposed EACA, three budget scenarios of $1.5/day, $2.0/day and $2.5/day are performed. The results of each of the scenarios using EACA are compared to five base cases in which the appliances are randomly used. The simulation results revealed that the proposed EACA obtained an optimal absolute comfort with reduced cost per unit comfort values for all three scenarios within the budget limits. [ABSTRACT FROM AUTHOR]

Utilizing of supervisory control theory on the real systems in many modeling tools such as Petri Net (PN) becomes challenging in recent years due to the significant states in the automata models or uncontrollable events. The uncontrollable events initiate the forbidden states which might be removed by employing some linear constraints. Although there are many methods which have been proposed to reduce these constraints, enforcing them to a large-scale system is very difficult and complicated. This paper proposes a new method for controller synthesis based on PN modeling. In this approach, the original PN model is broken down into some smaller models in which the computational cost reduces significantly. Using this method, it is easy to reduce and enforce the constraints to a Petri net model. The appropriate results of our proposed method on the PN models denote worthy controller synthesis for the large scale systems. [ABSTRACT FROM AUTHOR]

Distributed drive electric vehicle(DDEV) has been widely researched recently, its longitudinal stability is a very important research topic. Conventional wheel slip ratio control strategies are usually designed for one special operating mode and the optimal performance cannot be obtained as DDEV works under various operating modes. In this paper, a novel model predictive controller-based multi-model control system (MPC-MMCS) is proposed to solve the longitudinal stability problem of DDEV. Firstly, the operation state of DDEV is summarized as three kinds of typical operating modes. A submodel set is established to accurately represent the state value of the corresponding operating mode. Secondly, the matching degree between the state of actual DDEV and each submodel is analyzed. The matching degree is expressed as the weight coefficient and calculated by a modified recursive Bayes theorem. Thirdly, a nonlinear MPC is designed to achieve the optimal wheel slip ratio for each submodel. The optimal design of MPC is realized by parallel chaos optimization algorithm(PCOA)with computational accuracy and efficiency. Finally, the control output of MPC-MMCS is computed by the weighted output of each MPC to achieve smooth switching between operating modes. The proposed MPC-MMCS is evaluated on eight degrees of freedom(8DOF)DDEV model simulation platform and simulation results of different condition show the benefits of the proposed control system. [ABSTRACT FROM AUTHOR]

The paper presents the human Affect Reward Based Automation Ambient Comfort Controller (ACARBC) as the interconnected cloud computing intelligent services that provide intelligent calculus for any instrumented interconnected environment sense and control system. The ACARBC has been modelled and, as the experimental results show, that an environmental state characteristics that create an optimum ambient comfort can be obtained by ACAR index. The ACAR index is dependent on human physiological parameters: the temperature, the ECG- electrocardiogram and the EDA-electro-dermal activity. The fuzzy logic is used to approximate the ACAR index function by defining two fuzzy inference systems: the Arousal-Valence System, and the Ambient Comfort Affect Reward (ACAR) System. The Radial Basis Neural Network is used as the main component of the ACARBC to performing of two roles - the policy structure, known as the Actor, used to select actions, and the estimated value function, known as the Critic that criticizes the actions made by the Actor. The Critic in this paper was used as a value function approximation of the continuous learning tasks of the ACARBC. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a novel wind turbine control system which gives a smooth power output during transitions between different controllers. The paper presents an implementation of a control system designed for an offshore floating wind turbine using a linear Model Predictive Control approach.The performance is investigated in computer simulations, with emphasis on stability in the tower fore–aft motion and behaviour during transition between controllers. The results clearly demonstrate that the wind turbine using the proposed algorithm for smooth transition indeed exhibits a smooth system behaviour. In comparison to a case with sudden transition, the behaviour is found to be significantly improved. Moreover, tower oscillations are found to be stable, by virtue of the controller prediction horizon exceeding the natural periodicity of the tower oscillations.Smooth system behaviour is important to increase the lifetime of critical parts of the turbine. With increasing turbine sizes such considerations are of increasing importance, making the results obtained in this paper of particular relevance for large wind turbines, both onshore and offshore. [Copyright &y& Elsevier]

In the sight of the higher requirement about operation speed and control accuracy in satellite attitude control system, this paper analyzed the feasibility of PD attitude controller by using FPGA, and proposed a method using the input enable and the output control symbol to dominate the internal calculation module to figure out the problem of data synchronization. The paper used hardware description language to achieve the function of each module, and finally instantiated the IP core of PD controller. The result shows that the design is able to accomplish the calculation of attitude control torque by only using 34 clock pulses and the accuracy of control can reach 10-5 magnitude. The speed and accuracy meet the needs of the modern small satellite control system and lay the foundation for using FPGA implementation in small satellite attitude control system. [ABSTRACT FROM AUTHOR]

Abstract: This paper brings forward the Single-Current-Based method which can realize the output power of the solar cell reach the maximum value within this period of time by controlling the current to maximum. The paper firstly elaborates the principle and the function of Single-Current-Based MPPT strategy, and then it includes the main design of DC-DC convertor, and the design of stepping PWM controller which base on the CMOS digital circuit hardware logical programming. Besides, the paper shows the experimental process and results in detail for the analysis of the feasibility of the system and shows its success on achieving the effect of Single-Current-Based method of the MPPT controlling system, which also shows the advantages from other maximum power point tracking strategies. [Copyright &y& Elsevier]

Abstract: In order to improve the control performance of boost converter with large signal disturbance, a composite PWM control strategy for boost converter operating in continuous condition mode (CCM) was proposed in this paper. The parasitical loss of Boost converter was analyzed and a loss compensation strategy was adopted to design feed-forward tracker for converter. The composite PWM controller consisted of the tracker and PID controller. Simulation and experiment results validated the validity of the control strategy presented in this paper. [Copyright &y& Elsevier]

Abstract: In this paper, human-computer interaction was applied as the main features. Human-computer interface programs and programmable logic controller (plc) programs were combined application and address matching and the same address communication mode were adopted. Through the buttons of human-computer interface to trigger the read address set. And further corresponding virtual relays of the plc addresses area were activated. In this paper, Li/MnO2 button battery product line control system was introduced as an example. In the system, according to the process route of product line some areas were set including parameter setting area, single working place debugging area, equipment running area and the alarm browsing area. In order to protect the normal operation of the product line, interlock programs were used to ban parameters modification and single station debugging, avoiding the occurrence of malfunction. At the same time, the fault diagnosis technology was used to have designed a more optimal alarm pattern. The control system has been tested in practice to get good results. [Copyright &y& Elsevier]

Abstract: A new design of decentralized load-frequency controller for interconnected power systems with ac-dc parallel using Particle Swarm Optimization (PSO) algorithm is proposed in this paper. A HVDC link is connected in parallel with an existing ac tie-line to stabilize the frequency oscillations of the ac system. Any optimum controller selected for load frequency control of interconnected power systems should not only stabilize the power system but also reduce the system frequency and tie line power oscillations and settling time of the output responses. In practice Load Frequency Control (LFC) systems use simple Proportional Integral (PI) or Integral (I) controller parameters are usually tuned based on classical or trial-and-error approaches, they are incapable of obtaining good dynamic performance for various load change scenarios in multi-area power system. For this reason, in this paper the PI and I control parameters are tuned based on PSO algorithm method for the LFC control in the two-area power system. A two area interconnected thermal power system is considered to demonstrate the validity of the proposed controller. The simulation results show that the proposed controller provides better dynamic responses with minimal frequency and tie-line power deviations, quick settling time and guarantees closed-loop stability margin. [Copyright &y& Elsevier]

A time-varying generalization of the classical deadbeat controller is derived directly from input-output data in the present paper. The natural extension of the time invariant deadbeat condition to the time-varying case is presented by using the key developments of the observer/Kalman filter time-varying system identification theory reported recently by the authors. In stark contrast to the time invariant deadbeat controller design, it is shown that the time- varying deadbeat controller parameters do not follow the recursive relationship that was developed in the past. In the special case of periodic systems, where repeated experimental data are available naturally, it seems that such a controller can be designed to set the output of the closed-loop system to rest after a few time steps. Numerical simulation example demonstrates the efficacy of the deadbeat controller design method proposed in this paper. A deadbeat controller, realized from the departure motion dynamics of a spacecraft, is then shown to enhance the performance of an attitude control system by minimizing the deviations from a reference trajectory. [ABSTRACT FROM AUTHOR]

Abstract: According to a nonlinear current-voltage characteristic Photovoltaic for exploitation of this optimization we need to track maximum output instantly. The aim of this paper is to search maximum power point (MPP) Based on the Type2 Fuzzy logic controller (T2FLC) which is a novel method in maximum power point tracking (MPPT). Solar cells’ MPP varies with solar insolation and ambient temperature. With the improved efficiencies of power electronics converters, it is now possible to operate photovoltaic (PV) power systems at its MPP in order to improve the overall system efficiency. This paper presents a T2FLC method for tracking MPP in photovoltaic power systems and the control system is established simultaneously. The results of simulation show that the T2FLC significantly improves the robustness of controller''s PV during the tracking phase as compared to a conventional type1 fuzzy logic control (T1FLC) in present of noise in photovoltaic power systems. This noise maybe insert to system when voltage and current are measured. We show that the results obtained with T2FLC are better than the ones obtained with the T1FLC method. [Copyright &y& Elsevier]

Abstract: The main purpose of this paper is to design a decentralized controller for some car-like (wheeled) multi robots to follow and hunt a moving target. Considering geometric dimensions, mass and moment of inertia, robots are very similar to actual cars in which the outputs of the controller are steering and driving wheel torques. All robots are equipped with range and bearing sensors along with antenna, to communicate radio wave signals. A Kalman filter is implemented to estimate relative position, state variables of the target and state variables of other robots. The controller is designed to carry out the group maneuver of the system, based on the system dynamics analysis of inertial agents, as well as minimizing the norm of the error between desired and actual acceleration. A simulation study considering the group maneuver of four robots has been carried out, and the achieved results in positions, velocities and other relevant state variables of agents are depicted in the paper. The control torques of the steering system and driving wheels are derived and depicted appropriately. These results guarantee the performance of the addressed controller coupled with the Kalman filter, despite the existence of nonholonomics in dynamics, inertial behaviors, etc. [Copyright &y& Elsevier]

Abstract: In this paper, a digital redesign methodology of the iterative learning-based decentralized adaptive tracker is proposed to improve the dynamic performance of sampled-data linear large-scale control systems consisting of interconnected multi-input multi-output subsystems, so that the system output will follow any trajectory which may not be presented by the analytic reference model initially. To overcome the interference of each sub-system and simplify the controller design, the proposed model reference decentralized adaptive control scheme constructs a decoupled well-designed reference model first. Then, according to the well-designed model, this paper develops a digital decentralized adaptive tracker based on the optimal analog control and prediction-based digital redesign technique for the sampled-data large-scale coupling system. In order to enhance the tracking performance of the digital tracker at specified sampling instants, we apply the iterative learning control (ILC) to train the control input via continual learning. As a result, the proposed iterative learning-based decentralized adaptive tracker not only has robust closed-loop decoupled property but also possesses good tracking performance at both transient and steady state. Besides, evolutionary programming is applied to search for a good learning gain to speed up the learning process of ILC. [Copyright &y& Elsevier]

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Abstract: The stator-flux-oriented vector control strategy for double-fed induction motor was investigated in this paper. Three phase three-level rectifier was used as AC/DC block. This rectifier worked with low harmonic distortion in the grid side. Besides, it maintained a high power factor while the energy flows in bidirectional way. For the DC/AC converter, three-level inverter was adopted. Using stator-flux oriented vector control, the double-fed induction gained a high dynamic performance when the stator side was controlled operating in a unite power factor condition. In this paper a novel simplified space vector pulse width modulation (SVPWM) method was proposed to simplify the calculation. The neutral-point potential balance can be easily realized with this method. The control strategy was verified by experiments. [Copyright &y& Elsevier]

This paper illustrates the importance of controllers on energy saving opportunity of partial loaded three-phase induction motor in textile mill (ring spinning frame) applications. The economics of a scalar controlled 100 HP induction motor is investigated with three topologies namely star-delta (S/D) connection, constant Volt/frequency (V/f) controller and Differential Evolution (DE) controller in steady-state conditions. In this study, the flux level in a machine has been considered to adjust to give minimum operating cost for the textile mill load. The flux controller improves the economics in terms of operating cost (energy cost and demand charge cost) and the test results show that the flux level in the most economic motor will be adjusted according to load and speed, particularly at light load. Standard benchmark problems (Rastingin and Griewank) have been considered for validation of the proposed DE controller for induction motor operating cost minimization. Case study also presented in this paper. [ABSTRACT FROM AUTHOR]

In this paper a theoretical framework for retrofit reconfigurable flight control is developed and applied to a large class of nonlinear models of aircraft dynamics. The proposed approach solves a difficult problem of retrofit control design that retains a baseline controller and, at the same time, accommodates severe structural damage so that the overall system is stable and the control objective is met. This is accomplished using minimum prior information regarding the baseline controller. It is shown that the retrofit control design strongly depends on the properties of the nominal closed-loop system, which consists of the unperturbed system dynamics and the dynamics of the nominal controller. Using those properties in a judicious manner, it is shown that a retrofit control signal that compensates control effector damage and resulting state-dependent disturbances can be designed using the failure detection and identification subsystem and variable structure adaptation of suitably chosen signals within the proposed retrofit control architecture. In this paper, the focus is on the compensation of the control effector damage and resulting disturbances. It is shown that the proposed retrofit control design results in asymptotic convergence of the tracking error to zero. its properties are illustrated through simulations of a high-performance aircraft dynamics. The end result of the paper is a retrofit reconfigurable control design framework that is well suited for a large class of problems encountered in reconfigurable flight control. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method for non-scan design for testability of controllers that are logically synthesized from a finite state machine (FSM), which provides complete fault efficiency. In the previously used scan method, a test pattern for the combinational circuits of a controller was generated to achieve complete fault efficiency and was applied by using a scan flip-flop. However, in the scan method, the test sequence becomes large and various problems prevent the test from being performed at the actual operating speed. In this paper, the test pattern of the combinational circuits of the controller does not use scan flip-flops, but instead uses the state transitions of an FSM. The proposed method allows performance of the test at the actual operating speed of the circuit, thus reducing the testing time compared to the conventional methods. Moreover, experimental results using benchmarks show that the area overhead is small. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(5): 64–75, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1128 [ABSTRACT FROM AUTHOR]

This paper proposes the application of a Basic Variable Neighborhood Search algorithm in the coordinated and simultaneous tuning of the parameters of damping controllers known as power system stabilizer and thyristor-controlled series capacitor-power oscillation damping. The controllers are inserted into the multi-machine power system New England (10 generators, 39 buses and 46 transmission lines) in order to guarantee its small-signal stability. A current injection model for the thyristor-controlled series capacitor is presented and incorporated into the current sensitivity model, which is used to represent the electric power system and its components. The performance of the method proposed in this work is compared to three other methods found in the literature: local search, iterated local search and particle swarm optimization. The results show that, of the techniques analyzed, the Basic Variable Neighborhood Search is the most efficient for this type of problem, presenting high convergence rates and the shortest processing times with robust solutions considering different scenarios with load variations. [ABSTRACT FROM AUTHOR]

For starting high-voltage asynchronous motor, the voltage regulator based on current-limiting transformer is presented in the paper. Its mathematical model needs to be established analyzing and designing voltage regulator of high-voltage asynchronous motor. The mathematical model of the current-limiting transformer is deduced based on basic circuit theory. It can be found that a continuous variation reactance can describe the current-limiting transformer during starting process. The two variables functions of current and voltage are transformed into one-variable functions, and thus system control is greatly simplified. The voltage regulator is simulated on the basis. The simulation results show that this model has enough accuracy. Finally, the high-voltage asynchronous motor voltage regulator based on current-limiting transformer is designed and tested on this model. [ABSTRACT FROM AUTHOR]

This paper presents an anti-windup self-tuning euzzy proportional-integral-derivative (PID) controller for the speed control of brushless direct-current (BLDC) motor. The proposed controller consists of a self-tuning fuzzy PID controller and an snti-windup controller, which combines the merits of these two controllers. The anti-windup controller is designed as a fuzzy proportion controller and is switched by a logic function based on the output of proposed controller and the speed error. A detailed simulation study in MATLAB/Simulink is performed to investigate the performance of proposed controller, and the simulation experiments are conducted on different conditions. The control system parameters of the proposed controller such as overshoot, settling time and rising time are compared with that of the conventional PID controller. The simulation results show that the proposed controller can accelerate the response speed of BLDC motor, strengthen the ability of anti-windup and make motor runs smoothly, it is proven that anti-windup self-tuning fuzzy PID controller has better performance than conventional PID controller. [ABSTRACT FROM AUTHOR]

This paper is to implement an active wire tensioner which uses a cascade fuzzy logical controller to handle wire tension on a brush-less direct current (BLDC) coil winding machine during the winding process. A manifold winding process of the BLDC machine found by an analysis among various winding processes shows that the wire tension in winding process of the BLDC winding machine is more fluctuated than that in other winding processes. Based on the result of the analysis, a mechanism called as a wire accumulator using a pneumatic servo system is designed to decay the vibration of wire tension encountered with the harsh condition of winding process. In order to ensure the wire accumulator working properly, a magnetic powder clutch is adopted to prevent the wire passing through the wire accumulator freely. The active wire tensioner is defined as a multi-input single-output system with two control inputs for driving the magnetic powder clutch/the pneumatic cylinder and single output as the wire tension force. For such sophisticated behavior of the system's response, a novel cascade fuzzy logical controller (CC-FLC) with the fuzzy rule constructed based on a split-range method is appropriate for controlling the active wire tensioner. Additionally, the CC-FLC is convenient to be built into DSP alone-chip since its processing calculation consumes a low time. The effectiveness of the proposed active wire tensioner using CC-FLC is compared to that of a passive wire tensioner existing on the BLDC winding machine when both wire tensioners are used for coil producing process of the BLDC winding machine. Experimental results show that the BLDC winding machine equipped with the proposed active wire tensioner can operate at high winding speed without breaking the wire and reducing the coil size in the view of dimension. [ABSTRACT FROM AUTHOR]

The paper demonstrates remote control of thermo-optical plant via Android based mobile application. The user can run the experiment in an open or closed loop. The plant control is realized via predefined PID controller whose parameters can be changed. Another possibility is to use own customized controller whereby the control algorithm has to be defined using the syntax of SciLab environment that is running in background of the whole experiment. [ABSTRACT FROM AUTHOR]

In this paper, a brief overview of real time implementation of next generation Robust, Tracking, Disturbance rejecting, Aggressive (RTDA) controller and Model Predictive Control (MPC) is provided. The control algorithm is implemented through MATLAB. The plant model used in controller design is obtained using system identification tool and integral response method. The controller model is developed in Simulink using jMPC tool, which will be executed in real time. The outputs obtained are tested for various constraint values to obtain the desirable results. The implementation of Hardware in Loop is done by interfacing it with MATLAB using Arduino as data acquisition unit. The performance of RTDA is compared with those of MPC and Proportional Integral controller. [ABSTRACT FROM AUTHOR]

This paper considers the stabilization problem of a continuous linear system over a communication channel with network-induced delay. The channel is of finite data rate and connects the measurement sensor to the controller. Under the channel encoder without access to control inputs, a coding scheme based on spherical polar coordinates is proposed for this problem. Two cases are addressed: (1) in the case that the channel decoder does not utilize control inputs, instead of the original system, the corresponding augmented system is used to estimate the upper and lower bounds of the state norm of the original system for quantization, which simplifies the design of the coding scheme. And a definite relation between the quantized data and the corresponding quantization error is used to present the condition for the stability of the system; (2) in the case that the decoder utilizes control inputs, instead of quantizing the system state at each time step as usual, the encoder quantizes the initial state all the time by updating the parameters of the quantizer, which also simplifies the design of the coding scheme. Sufficient conditions guaranteeing that the system is stable are presented for the two cases, respectively, and the corresponding design methods for coding schemes are given. [ABSTRACT FROM AUTHOR]

The paper presents the position control of a permanent magnet synchronous motor by using the finite control set model predictive control. The position, speed and acceleration references are generated by a ramp generator. A new cost function, including feed-forward and load torque compensations, is introduced. In order to save the computational power, a combination of a predictive speed control with proportional position controller is explored as well. Presented methods are compared to the conventional field oriented control structure by a simulation. [ABSTRACT FROM AUTHOR]

Although adaptive control has been used in numerous applications to achieve system performance without excessive reliance on system models, the necessity of high-gain learning rates for achieving fast adaptation can be a serious limitation of adaptive controllers. Specifically, in safety-critical systems involving large system uncertainties and abrupt changes in system dynamics, fast adaptation is required to achieve stringent tracking performance specifications. However, fast adaptation using high-gain learning rates can cause high-frequency oscillations in the control response, resulting in system instability. This paper develops an output feedback adaptive control framework for continuous-time minimum-phase multivariable dynamical systems for output stabilization and command following to address the problem of achieving fast adaptation using high-gain learning rates for systems with partial state information. The proposed framework uses a controller architecture involving a modification term in the update law that filters out the high-frequency content in the control response while preserving uniform boundedness of the system error dynamics. The approach is based on a nonminimal state-space realization that generates an expanded set of states using the filtered inputs and filtered outputs, as well as their derivatives, of the original system, and requires knowledge of only the open-loop system's relative degree and a bound on the system's order. [ABSTRACT FROM AUTHOR]