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With the rapid growth of economy, the demand from different products for packaging is increasing, thus more needs are to meet on the performance of laminating machine. There are disparities between laminating machine made in China and other countries with advanced level in working speed. In order to solve the problem, a study on the electrical motor design is carried out. Servo motor is used to achieve smooth variable motion of paper drive shaft so as to reduce the velocity when the flute rams upper paper and avoid the folding and bending of paper. Through speeding up the moving speed of paper, the average speed of laminating is achieved, thus completing paper lamination at a rapid speed, which means the working efficiency of laminating machine is improved. Complete speed curves of paper transferring are made, tested and debugged in the study to meet different working demands. Research results show that the system can solve problems in upper paper folding and also improve the working efficiency and performance of laminating machine. [ABSTRACT FROM AUTHOR]

The interrupting duty of high-voltage circuit breakers can be reduced by increasing the contact parting time, which is the sum of tripping delay and the circuit breaker opening time. The contact parting time is fixed; however, the tripping delay can be increased. Although this method is not discussed in current technical literature, it is valid according to the ANSI/IEEE standards. Immediate replacement of the circuit breakers or other alternatives to reduce interrupting duties can be avoided, resulting in large cost savings and process downtime. The problem occurred in a large paper mill distribution system, where the circuit breakers were applied well within their close and latch ratings but the interrupting duty exceeded by 6%. By introducing an additional tripping delay of one cycle, the interrupting duty is reduced and the existing breakers are retained in service. This paper demonstrates these calculations. [ABSTRACT FROM AUTHOR]

The profitable commercialization and swift growth in electrified transportation requires load management controllers. Effective load management controllers can reduce the peak load on the power grid, balance the load demand and improve the stability of the power grid. Several techniques are available to optimize the load, including battery swapping, vehicle-to-grid (V2G), vehicle-to-vehicle (V2V) and vehicle-to-home (V2H) approaches. This paper addresses effects of rising adoption of electric vehicles (EVs) and the potential for an increased load on the distribution system, which requires load optimization to ensure sustainable development. This paper offers a comprehensive review of all possible energy management controllers used in EVs for load optimization and power split controllers for splitting power between the battery and super-capacitor in hybrid energy storage systems (HESS) to increase battery life span. These controllers are classified into three categories, fuzzy logic controller, voltage-based controller and soft computing-based controller, with their constraints, advantages and disadvantages and finally sum up with their current challenges and future recommendation. The paper also reveals the wireless charging with their pros and cons. The findings have implications for the design and implementation of controllers for EVs to ensure their sustainable development and reduce fossil fuel usage. This study will be highly helpful to the researchers, industrialist and investors as a ready literature of energy management controllers for EVs, with information of their recommendations and challenges. [ABSTRACT FROM AUTHOR]

This paper presents a simple motion controller of an electric wheelchair by using a push button panel, Arduino platform and a VR2 modified power electronic drive. The aim of this paper its to replace joystick controller by a push button panel, this solution is easy to use it by the cerebral palsy patient who has problems with coordination in their upper extremities(head and hands) and dystonia states. The speed control of the wheels and change the direction is implemented through a digital pulse-width modulation technique, which is varying with the reference generated, by incremented or decremented push button action. Experimental results demonstrate that the proposed solution meets the user requirements in terms of reliability and good driving. [ABSTRACT FROM AUTHOR]

Although the vehicle dynamics effects of variable anti-roll moment distribution actuated through active suspension systems are widely discussed in the literature, their model-based control has only been recently analysed, given the highly nonlinear nature of the involved dynamics. Moreover, the available studies do not discuss the trade-off between internal model complexity and controller performance, nor analyse the opportunities offered by vehicle connectivity, which enables the prediction of the steering angle and reference yaw rate profiles ahead. To address the gap, this paper introduces and assesses three optimal controllers for an electric vehicle with active suspensions, multiple powertrains, and a brake-by-wire system. The formulations are: (a) a gain scheduled output feedback linear quadratic regulator (OFLQR); (b) a nonlinear model predictive controller using a three-degree-of-freedom prediction model, without and with preview of the steering angle and reference yaw rate ahead, respectively referred to as NMPC-3 and NMPC-3-Pre; and (c) a nonlinear model predictive controller based on an eight-degree-of-freedom prediction model, referred to as NMPC-8 and NMPC-8-Pre depending on the absence or presence of preview. The results on an experimentally validated model show that: (i) NMPC-8 provides evident yaw rate tracking benefits with respect to (w.r.t) OFLQR and NMPC-3; and (ii) NMPC-8-Pre can bring ∼20% yaw rate tracking improvement w.r.t. an optimally tuned NMPC-8 configuration. [ABSTRACT FROM AUTHOR]

Copyright of Informatics Control Measurement in Economy & Environment Protection / Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska is the property of Lublin University of Technology 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.)

This paper presents a method to design an integrated path tracking and lateral stability controller for an autonomous electric vehicle with four-wheel independent steering (4WIS) on low friction roads. Recent advances in autonomous driving have led to extensive studies on path tracking control. However, path tracking is difficult on low friction roads. In this paper, path tracking control was converted to the yaw rate tracking one to cope with problems caused by low friction roads. To generate a reference yaw rate for path tracking, we present several methods using a driver model and a target path. For yaw rate tracking, we designed a controller with a two-layer control hierarchy, i.e., upper and lower layers. The control yaw moment was calculated using a direct yaw moment controller in the upper layer. In the low layer, a control allocation method was adopted to allocate the control yaw moment into steering angles of 4WIS. To verify the performance of the proposed controller, we conducted a simulation on vehicle simulation software. From the simulation results, it is shown that the proposed controller is effective for path tracking and lateral stability on low friction roads. To analyze path tracking and lateral stability performance of the proposed controller on low friction roads, the effects of the steady-state yaw rate gain are investigated from the simulation results. [ABSTRACT FROM AUTHOR]

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]

The integration of supercapacitors as hybrid energy storage systems in electric vehicles has attracted the attention of many researchers and has been considered as a promising solution. Bidirectional DC/DC converters (BDDCs) play a fundamental role in HESS, as they manage the power flow by controlling currents and regulating the DC bus voltage. However, they encounter the challenge of uncertainties and high fluctuation power loads, necessitating the fast dynamics, stability, and high robustness of the controller. This paper proposes a novel hybrid proportional–integral and backstepping cascade controller to regulate the DC‐bus voltage under uncertainties and load variations, and to control the current references of the on‐boarded sources. To confirm the asymptotic stability of the whole system, a nonlinear stability analysis is conducted using the Lyapunov theorem. A power management strategy is applied to distribute the power loads and generate reference currents for the BDDCs controller. Simulations results under various driving cycles using MATLAB/Simulink demonstrate the superiority of the proposed controller compared to conventional proportional–integral and backstepping controllers. A real‐time controller‐hardware‐in‐the‐loop test bench is developed to validate the effectiveness of the proposed strategy. [ABSTRACT FROM AUTHOR]

Emulation of an electric machine allows the testing of a drive inverter and controller of an electric drive system, prior to the manufacture of a machine prototype. This paper presents the emulation of a variable flux machine (VFM). The VFM emulator system proposed in this paper uses a detailed look-up table-based machine model for the purpose of emulation. This allows the emulator to mimic all machine magnetic and geometric behaviors such as saturation and torque ripple. In addition, the machine emulator proposed in this paper uses high-performance high-bandwidth linear amplifiers as power amplifiers. This enables a high bandwidth; leading to a high accuracy machine emulation. A detailed control description for the proposed machine emulator system and a machine model look-up table data verification against a prototype machine is initially presented. Experimental results are then presented to validate the utility of the proposed VFM emulator system to emulate various machine transient behaviors at different magnetization levels. Experimental results obtained from the emulator are subsequently compared against the experimental results obtained from a prototype VFM drive to verify the emulation accuracy. [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]

A smart battery electric vehicle control framework is proposed in this paper. The specific controller empowers ceaseless observation and management of the battery's state with the scope of extending the vehicle's driving range under varying temperature and driving pattern conditions. The proposed method utilizes an incorporated scheme for dealing with a crossover energy stockpiling framework to expand a battery's lifespan while further ensuring its smooth activity. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny 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.)

Recent developments in electrical power grids have witnessed high utilization levels of renewable energy sources (RESs) and increased trends that benefit the batteries of electric vehicles (EVs). However, modern electrical power grids cause increased concerns due to their continuously reduced inertia resulting from RES characteristics. Therefore, this paper proposes an improved fractional-order frequency controller with a design optimization methodology. The proposed controller is represented by two cascaded control loops using the one-plus-proportional derivative (1 + PD) in the outer loop and a fractional-order proportional integral derivative (FOPID) in the inner loop, which form the proposed improved 1 + PD/FOPID. The main superior performance characteristics of the proposed 1 + PD/FOPID fractional-order frequency controller over existing methods include a faster response time with minimized overshoot/undershoot peaks, an ability for mitigating both high- and low-frequency disturbances, and coordination of EV participation in regulating electrical power grid frequency. Moreover, simultaneous determination of the proposed fractional-order frequency controller parameters is proposed using the recent manta ray foraging optimization (MRFO) algorithm. Performance comparisons of the proposed 1 + PD/FOPID fractional-order frequency controller with existing PID, FOPID, and PD/FOPID controllers are presented in the paper. The results show an improved response, and the disturbance mitigation is also obtained using the proposed MRFO-based 1 + PD/FOPID control and design optimization methodology. [ABSTRACT FROM AUTHOR]

This paper develops a neural network-based fault tolerant LQR control for orbital maneuvering of satellites in low altitude orbit that are subjected to disturbances like earth gravity, atmospheric drag, third body, and solar radiation. The controller is also developed such that it tolerates the effects of additive and effective loss of actuator faults. A neural network is used in the controller to estimate disturbances and faults and decrease their effects. Due to the high efficiency of electric thrusters, they are used widely in LEO (Low Earth Orbit) missions. Therefore, in this paper Hall effect thrusters are used as the actuator. For the maneuvering purpose, the reference orbit parameters are derived from a reference orbital dynamics which is the Kepler dynamics subjected to only the disturbance of gravity. To avoid singularity, the orbital dynamics of six modified elements are used in the control design besides the six classical elements. Then, by the desired orbital parameters from the reference orbit, the relative motion elements are calculated to apply in control laws. By Lyapunov analysis, the updating laws of the weights of the control and neural network are derived and also ultimately boundedness of the error between the nominal orbital elements and the faulty orbital elements is proved. To show the effectiveness of the proposed control, it is applied in the nonlinear Kepler dynamics which is affected by an accurate model of natural disturbances. [ABSTRACT FROM AUTHOR]

This paper clearly demonstrates the structure of Experimental Advanced Superconducting Tokamak (EAST) power supply system and analyzes principles of the finite-state machine (FSM) elaborately. Depending on the characteristics of EAST power supply system and the requirements of it, this paper chooses the real-time Linux as system platform and experimental physics and industrial control system (EPICS) as development tool to design a control system of the EAST poloidal field power system supply. This paper utilizes a temporal logic control based on the FSM in order to regulate the operation process of real-time sequence logic control of 12 sets of power controllers. This design is evaluated and tested, and it completely meets the real-time requirement of the poloidal field power supply (PFPS) control system. Several experiments have proved that this design definitely meets the real-time sequence logic control requirement of the PFPS control system in the complex situations under magnetic fields. [ABSTRACT FROM AUTHOR]

In the paper by Patra et al., a single-inductor multiple-output switcher was presented to produce buck, boost, and inverted outputs simultaneously. Unfortunately, this study showed some unexpected mistakes, especially in state-space equations and in the calculation of output voltages. The objective of this note was to provide correct analysis and rectify the errors in this paper. Some tables and equations have been modified that were present in the initial draft of this paper. The obtained parameters in this work could be an effective supplement and extension for the original work in the paper by Patra et al. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes an advanced power converter setup to charge an electric vehicle battery from a renewable energy source, such as solar photovoltaic. An improved Z‐source DC–DC boost converter (IZSBC) is utilized in the first stage. A synchronous rectifier (SR) of a phase‐shifted full‐bridge converter (PSFBC) with continuous conduction mode (CCM) is employed in the second stage using the zero voltage switching (ZVS) technique to provide isolation between the source and the load. To address the disadvantage of undesirable dynamic characteristics of the PSFBC‐SR, an advanced voltage control using the advanced model predictive controller (AMPC) is suggested to improve the dynamic characteristic of the PSFBC‐SR converter and prevent output voltage overshoot. An AMPC‐based new control method is preferred to eliminate body‐diode conduction for improved efficiency at any load conditions. Simulation and experimental designs of 0.5 kW with a 25 V DC input from the SPV, a boosted output of 100 V for a 60 V, 16 Ah battery bank and switching frequencies of 100 and 250 kHz for IZSBC and PSFBC‐SR, respectively, are produced and evaluated. Results show an efficiency of 93.7% with 31.44 W loss in simulations and 93.94% with 30.25 W loss in hardware tests. The preferred system has fast dynamics and is robust to sudden load impedance changes, thereby improving current tracking and reducing converter losses. The AMPC strategy proposed in this paper can increase conversion efficiency and control the output voltage without additional gain tuning. [ABSTRACT FROM AUTHOR]

According to the modification requirement for the flywheel tightening device in the assembly line of a well-known automobile manufacturer, this paper designs an electrical control system for flywheel tightening device with the Schneider TXS57 series controller and the XBTGK2330 touch screen as the control core. In order to achieve the precise control over the torque, angle and other parameters during bolt tightening, this paper performs some basic mechanics analysis and experiment on the current bolt tightening methods and techniques, and finally selects the torque-angle method. Under this method, two wrenches are added and tightening is performed according to settings, which makes up for the insufficient capacity of the company, and helps ensure its normal production and operation. The system studied and designed in this paper is of great significance to promoting the application of flywheel tightening devices in automobile engine assembly. It can manage and control tightening data at limited costs, which is an excellent solution for the information construction at factory. [ABSTRACT FROM AUTHOR]

A large class of three-phase electrical power systems possess symmetry conditions that make it possible to describe their behavior using single-input single-output transfer functions with complex coefficients. In such cases, an extended root locus method can be used to design control laws, even though the actual systems are multi-input multi-output. In this paper, the symmetric conditions for a large class of power systems are analyzed. Then, the root locus method is revisited for systems with complex coeffcients and used for the analysis and control design of power systems. To demonstrate the benefits of the approach, this paper includes two examples: 1) a doubly fed induction machine and 2) a three-phase LCL inverter. [ABSTRACT FROM PUBLISHER]

This paper presents a literature review on magnetically-controlled devices, variable inductors (VI), and variable transformers (VT), and their applications to lighting gears for discharge lamps and/or LED lamps. These current-controlled devices are mainly characterized by nonlinear and non-uniform saturation of the magnetic core. The paper describes the fundamentals and basic operating principle of such devices and provides an overview of existing patents. These patents refer the devices, VIs or VTs, as useful or industrially applicable. Some present one or more claims regarding the construction of the device and behavioral characteristic; others refer to specific applications, such as voltage regulation or universal ballast operation. Afterwards, the paper focuses on the review of specific techniques and circuits taking advantage of the presence of a controlled inductance value, by covering recent applications regarding discharge and solid-state lamp drivers. These applications will show how these multi-winding devices, typically not considered due to their low efficiency, may fulfill an important role and add features to state-of-the-art lamp drivers. [ABSTRACT FROM AUTHOR]

This paper uses the five-level neutral-point clamped (NPC) inverter to feed an electric vehicle's traction motor-interior permanent magnet synchronous motor (IPMSM). The model predictive control method controls the energy conversion process according to the model with two prediction steps. The advantage of this method is its fast response, which increases the ability to operate the converter with good voltage quality. Model predictive control (MPC) control is a closed-loop strategy with much potential when integrating multiple control objectives; the calculation process is compact without complex modulation. Within the scope of this article, the MPC strategy will be implemented with two control goals for NPC, including output load current and capacitor voltage balance with low switching frequency. The simulation results on MATLAB/Simulink software were performed to verify the proposed algorithm's effectiveness in minimizing the grid current's harmonics and ensuring an uninterrupted power supply. [ABSTRACT FROM AUTHOR]

Operational life of power transformers and reactors are vastly challenged by several phenomenons capable of causing complete disruption to their insulations and winding structures. Corrosive sulphur is one of the major concerns in the recent past because of its complex dynamics in causing failures to power transformers and reactors. Several failures have been reported due to deposition of copper sulphide (Cu2S) on copper conductor and paper insulations. Effective identification of corrosive sulphur, extraction of chemical compositions of oil and paper insulation affected by corrosive sulphur and its reflection on the electrical properties, development of possible long term mitigation techniques are gaining importance among investigating agencies and industries. This paper is mainly intended to survey major experimental investigations, results and suggestions registered so far on the formation and effects of corrosive sulphur in transformer insulation system. [ABSTRACT FROM AUTHOR]

Large power systems usually comprise more than one area connected together. Load frequency control becomes an important issue, especially with increasing size and complexity of Interconnected Power System (IPS). This paper is a review paper which contains different control schemes and different optimization techniques applied on different controllers to get the desired response of the system frequency and the power in the tie lines connecting the areas. The comparison is done from the point of view of the maximum shooting, settling time, and the system damping. The system under study is a multi-area system (2 areas, 3 areas, etc.). Controller types and optimization techniques will be reviewed latter in each reference. [ABSTRACT FROM AUTHOR]

Shape memory alloys (SMAs) exhibit a unique property that undergoes deformation in response to temperature variation. This characteristic can be utilized via the application of a filiform SMA wire to tendon-driven robotic actuators for biomimetic joint movements. However, due to the inefficiencies in heat dissipation, conventional SMA tendon-driven actuators are characterized by their lower relaxation speeds than other actuators. This paper proposes a novel cooling design for an SMA tendon-driven actuator using thin-fin heat sinks based on a multi-layer wrapped SMA tendon design. In addition, the electric circuit and the controller are refined. Prototype devices are constructed to validate the performance of SMA-based actuators under PID control. The results indicate that the proposed design exceeds previous models in terms of relaxation performance by up to 5.8 times while also being able to stabilize at a target angle within 0.5 s under control. [ABSTRACT FROM AUTHOR]

Impedance Control (IC) and Admittance control (AC) are two control methods for robot-environment interaction which have opposing performance and stability characteristics. Previous research has proposed that the two controllers define a spectrum of controllers. This paper quantifies the IC/AC spectrum as a trade-off between the suppression of force sensor error and modelling error. Unified Interaction Control (UIC) is introduced, which can interpolate across this spectrum of controllers by using a periodic state-reset and an inner-loop gain weighting parameter. The UIC is verified through simulation, experiment, and an eigenvalue analysis. Interpolating across the spectrum allows one to choose an ideal controller given the nature of the robot and environment. This is demonstrated in two case studies: adapting the level of interpolation to optimize performance with a changing environment, and using a static level of interpolation to mitigate the worst-case effects in both IC and AC. [ABSTRACT FROM AUTHOR]

In this paper, a data-driven controller design approach for batch processes is proposed. In this strategy, based on a suitable transformation of the input and output signals, a mathematical description of the process dynamics is not needed, and the working cycle is guaranteed to adapt to the desired operating conditions. Throughout this paper, all the steps of the above algorithm are described in detail with the help of an experimental case study dedicated to a gravimetric blender, which is a key element in the plastic extrusion process. [ABSTRACT FROM PUBLISHER]

The ever growing penetration of distributed generation (DG) in a distribution network has a profound impact on network protection and stability. Traditional protection schemes and algorithms need to be extensively investigated as more and more DGs get introduced into the network. The current version of IEEE Standard 1547 does not present a comprehensive solution for fault current detection in the presence of various kinds of DGs. Power electronic inverter-based DGs (IBDGs) are of special concern in distribution network protection as they are often incapable of providing sufficient fault current and their controllers play a principal role in the DG behavior. In this paper, the effects of voltage and current controllers for IBDGs on industrial and commercial power system protection schemes are investigated. It is shown that the inverter control mode has a direct impact on its fault current levels and duration. A simplified distribution network model with IBDG operating under voltage and current control modes was tested to verify the effects of these controllers. This paper also proposes an adaptive relaying algorithm to detect the faults in the presence of IBDGs with various types of controllers. [ABSTRACT FROM AUTHOR]

This paper presents three types of optimization techniques; Teaching Learned Based Optimization (TLBO), Harmony Search Algorithm (HSA), and Local Unimodal Sampling (LUS) which are used to tune the controller parameters in Automatic Voltage Regulator (AVR) system. AVR system is used to adjust the terminal voltage of synchronous generator. This paper presents two types of controllers: Proportional-Integral-Derivative (PID) and Proportional-Integral-Derivative-Acceleration (PIDA). Each controller is used with TLBO, HSA, and LUS. For PID controller, these techniques show better performance than Many Optimizing Liaisons (MOL), Gravitational Search Algorithm (GSA), Artificial Bee Colony (ABC), Particle Swarm Optimization (PSO), and Differential Evolution (DE) in previous works. For PIDA controller, these techniques show better performance than Bat Search (BAT), Current Search (CS), Tabu Search (TS), and Genetic Algorithm (GA) in previous works. By comparing both controllers, PIDA shows better response in overshoot and steady state error than PID. [ABSTRACT FROM AUTHOR]

In order to strengthen the onshore transmission network in many parts of the world, voltage-source current–high-voltage direct current (VSC–HVDC) will increasingly be utilized. The effect of the operating point of a VSC-HVDC link and the control strategies employed can substantially affect the electromechanical oscillatory behavior of the ac network as well as the dc-side dynamics. In order for the full, flexible capability of VSC-HVDC to be exploited, further study of the effects of these controllers and their interactions with ac system responses is necessary. This paper addresses this gap. Both modal analysis and transient stability analysis are used to highlight tradeoffs between candidate VSC-HVDC power controllers and to study the electromechanical performance of the integrated ac/dc model. Tests are carried out on both a generic two-area model and a large-scale realistic network with detailed ac generator and HVDC models. [ABSTRACT FROM PUBLISHER]

This paper presents low-power circuit techniques for comparators and controllers to reduce increasing power loss of an active diode with offset/delay calibration in a 13.56-MHz CMOS active rectifier. Unlike a conventional switched-offset comparator, the proposed voltage-mode switched-offset comparator reuses its bias current to generate continuously adjustable offset voltage, thereby reducing power loss. Offset calibration for accurate switching is adopted to improve power conversion efficiency (PCE) and voltage conversion ratio (VCR). The proposed switch controller for offset calibration uses dynamic logic circuits and reduces power overhead that NOR-based set-reset latches and edge detectors of conventional switch controllers cause. Under 200- ${\Omega }$ loading and 5-V output, the proposed comparator and controller reduce power consumption by up to 73% and 24% in simulations compared with the conventional comparator and controller, respectively. This paper is implemented with 5-V devices of a 0.35- ${\mu }\mathrm {m}$ CMOS process to support high voltage. A peak PCE of 89.0%, a peak VCR of 90.1%, and a maximum output power of 126.7 mW are measured for 200- ${\Omega }$ loading. [ABSTRACT FROM AUTHOR]

Dealing with convergence time and dealing with steady state are two of the most challenging problems in the field of stability of the hydraulic turbine governing system. In this paper, we solve these two challenging problems by designing fixed-time feedback controllers. The design of the controllers is based on the fixed-time theory and backstepping method. Compared with the existing controllers for fixed-time, finite-time, and other techniques, the designed controllers make the maximum convergence time of the system unaffected by the initial state. The convergence time is also shorter. Meanwhile, they are continuous and do not include any sign function, and hence, the chattering phenomenon in most of the existing results is overcome via nonchattering control. In addition, they give the system better stability and robustness to disturbances. Finally, the numerical simulation results in this paper will contribute to a better understanding of the effectiveness and superiority of the proposed controllers. [ABSTRACT FROM AUTHOR]

To improve the structure layout flexibility and performance of the X-by-wire (XBW) ground vehicle, the control configured vehicle (CCV) principle is implemented on an XBW electric vehicle in this paper. By including the electric control system design together with the mechanical component design for the final layout, the CCV enhances the structure layout flexibility of the XBW ground vehicle considerably. Under the CCV principle, the closed-loop stability of the vehicle lateral dynamics system is improved by the involved yaw control system. In this paper, a robust pole assignment yaw controller with the consideration of parametric uncertainties is used. A full XBW electric vehicle testbed is shown as an example to demonstrate the benefit of the CCV of improving the hardware layout flexibility. Under the CCV, all the XBW components can be located flexibly to any position to enhance the configuration of the electric wires, saving of the space, and convenience of the assembling. The discussion of the yaw moment demand in different cases shows how the mechanical components and electric control systems influence and benefit each other in the CCV. The experiments based on the testbed show the desirable efficiency of the proposed yaw controller. [ABSTRACT FROM PUBLISHER]

Summary: In this paper, we consider the dual‐rate sampled‐data state‐feedback control problem for an active suspension system of an electric vehicle. In the active suspension system, there exist 2 accelerometers to measure the heave acceleration of the sprung mass and the vertical acceleration of the unsprung mass, respectively. When the 2 accelerations are measured by sampled data under different sampling periods, the difficulty arising from the dual‐rate sampled data makes the active suspension stabilization problem challenging but interesting. In this paper, a linear hybrid stabilizer is proposed, which is implemented using dual‐rate sampled‐data state feedback. In order to deal with the more difficult stabilization problem under different triggering time instants, a coordinate transformation is proposed. A useful technical theorem is proposed in the stability analysis to show that the proposed hybrid controller can guarantee the states of the active suspension system being asymptotically stabilized or at least bounded to arbitrarily small domains. The experiment result is similar to the simulation result and indicates that the proposed active suspension controlling system is effective. [ABSTRACT FROM AUTHOR]

In this paper, dynamic performance of automatic generation control (AGC) of two area thermal–thermal power system is determined through the steam chest and reheater constant trajectories. In earlier AGC studies, steam chest and reheater time constants denoted as T\text{SC} and T\text{RH} are considered to be constant, irrespective of plant generation schedules. However, it is discovered that T\text{SC} and T\text{RH} follow the specific trajectories with the plant generation schedules. These time constant trajectories are determined by the power output control strategies being employed to change the plant generation schedules. These control strategies are the different combinations of steam pressure versus flow rate curves used to operate the plant at different generation schedules. In this paper, time constant versus generation schedule trajectories of T\text{SC} and T\text{RH} have been derived for different power output control strategies. Furthermore, these time constant trajectories have been utilized to investigate the dynamic performance of two area reheat thermal power system. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of higher derivative input shaping for minimizing both oscillations, namely hook and payload of a multimode double-pendulum overhead crane (MDPOC) system. The MDPOC has greater nonlinearities and stronger internal couplings, especially when involving two oscillation frequencies with multimode dynamic effects. With a suitable system's natural frequency and damping ratio of the hook and payload oscillations, multimode zero-vibration (ZV-ZV), multimode zero-vibration derivative (ZVD-ZVD) and multimode zero-vibration derivative-derivative (ZVDD-ZVDD) shapers are successfully designed. More interestingly, two scenarios under a fixed cable length and a payload hoisting are considered which are closer to the real practical crane. Thus, an average travel length (ATL)-based shaper method is also considered to further verify the effectiveness and robustness of efficient hook and payload oscillation control under payload hoisting. All the multimode input shaping is simulated using the Matlab software. The simulation results of multimode ZVDD-ZVDD shaper successfully reduced in the overall hook and payload oscillations by 97.9% and 97.2%, respectively, compared to the unshaped system, whereas the multimode ATL-ZVDD shaper reduced hook and payload oscillations by 94.8% and 94.0%, respectively. In fact, the multimode ZVDD-ZVDD and multimode ATL-ZVDD shapers demonstrate the superiority in minimizing the hook and payload oscillations compared to the multimode ZV-ZV, multimode ZVD-ZVD, ATL-ZV and ATL-ZVD shapers. This significant reduction in oscillations enhances the precision and safety of real-world crane operations in industrial settings. It has been proven that considering the additional derivative of input shaping results in a higher level of hook and payload oscillations reduction. [ABSTRACT FROM AUTHOR]

In this paper design and simulation of a rule-based controller explained with performance analysis by using an adaptive-neuro-fuzzy and hybrid electric energy storage system to regulate power flow of electric propulsion in EVs named as (ANF-RBC) controller. In this proposed controller a hybrid electric energy storage system (HEESS) generated reference current and proposed controller for decreasing non-linear similarity generated by the usage of HEESS. Performance analysis of proposed controller carried out under three different load conditions and comparative analysis performed with existing one linear and three non-linear controllers. For performance trac under various loaded conditions done with greater than or equal to 90 % of battery current. By observing performance results of proposed controller, reducing non-linearity generated by HEESS and smooth tracking done well than that of traditional linear and non-linear controllers used in EVs. In performance analysis by using obtained results, we can infer proposed controller 17 %, 12 %, 10 % higher than existing RFOSM control, when compared with ASMC controller the proposed controller 25 %, 17 %, 13 % greater, proposed controller performance is 29 %, 21 %, 15 % greater than that of SMC controller and in case of comparing with existing PIDC controller with that of proposed controller performance is 32 %, 26 %, 19 % greater under heavily loaded, mediumly loaded and under lightly loaded condition respectively for all linear and non-linear traditional controllers. [ABSTRACT FROM AUTHOR]

Software-defined networking (SDN) is a trending networking paradigm that focuses on decoupling of the control logic from the data plane. This decoupling brings programmability and flexibility for the network management by introducing centralized infrastructure. The complete control logic resides in the controller, and thus it becomes the intellectual and most important entity of the SDN infrastructure. With these advantages, SDN faces several security issues in various SDN layers that may prevent the growth and global adoption of this groundbreaking technology. Control plane exhaustion and switch buffer overflow are examples of such security issues. Distributed denial-of-service (DDoS) attacks are one of the most severe attacks that aim to exhaust the controller's CPU to discontinue the whole functioning of the SDN network. Hence, it is necessary to design a quick as well as accurate detection scheme to detect the attack traffic at an early stage. In this paper, we present a defense solution to detect and mitigate spoofed flooding DDoS attacks. The proposed defense solution is implemented in the SDN controller. The detection method is based on the idea of an statistical measure d Interquartile Range (IQR). For the mitigation purpose, the existing SDN-in-built capabilities are utilized. In this work, the experiments are performed considering the spoofed SYN flooding attack. The proposed solution is evaluated using different performance parameters, i.e., detection time, detection accuracy, packet_in messages, and CPU utilization. The experimental results reveal that the proposed defense solution detects and mitigates the attack effectively in different attack scenarios. [ABSTRACT FROM AUTHOR]

This paper is concerned with velocity control in brushless direct current (BLDC) motors. Our control scheme is composed of a classical proportional–integral velocity controller and a proportional electric current controller computed in the extended dq coordinate system. We employ a finite time estimator that has been previously proposed in the literature intended to estimate the unknown back electromotive forces. This estimator has been proven previously to converge locally to the true values. This control strategy is proposed to eliminate torque ripple produced by the fact that back electromotive forces in BLDC motors are nonsinusoidal. We present, for the first time, a formal stability result for this control scheme: (a) the state has an ultimate bound provided that the estimate of the back electromotive forces is close to the true values, and (b) this ultimate bound can be rendered arbitrarily small when the estimate of the back electromotive forces converges to the true values. This result stands when starting from any initial condition such that the finite time estimator is ensured to converge to the true values. We verify our findings through simulations. [ABSTRACT FROM AUTHOR]

Continuous varying load demand conditions in modern power systems causes frequency variations. Hence, an intelligent controller is necessary for frequency regulation. In this paper, a hybrid African Vulture Optimization Algorithm and Pattern Search (hAVOA-PS) based Fractional Order PID controller with derivative Filter (FOPIDF) is suggested for Automatic Generation Control (AGC) of Electric Vehicles (EVs) integrated power systems. Proposed hAVOA-PS algorithm is first tested using four bench mark test functions and compared with original African Vulture Optimization Algorithm (AVOA), Differential Evolution (DE), Gravitational Search Algorithm (GSA), Particle Swarm Optimization (PSO) to show its superiority. The proposed technique is then used to tune various conventional controllers in a single area three-unit power system consisting of thermal hydro and gas power plants for AGC. The superiority of proposed hAVOA-PS algorithm over some recently proposed frequency control approaches has been demonstrated. In the next step, different controllers like PI, PID, and FOPIDF are taken and EVs are integrated in the power system. The proposed approach is also extended to a two-area six-unit power system. It is observed that EVs contribute to control system frequency in presence of load disturbance. [ABSTRACT FROM AUTHOR]

This paper discusses the basic principles of operation of a controller intended to limit the electrical energy consumption. The energy consumer is controlled depending on the amount of energy used, the magnitude of the load current and the pre-set permissible twenty-four-hour limit of electricity. The following possible situations are covered: the consumer has used energy equal to or less than the limit set within a 24-hour period; the consumer has used up the entire energy limit in less than 24 hours; the current through the consumer periodically exceeds the pre-set current limit; and training the consumer to use energy wisely by applying sanctions - temporary disconnections of the power supply. The method for programming and configurating the controller by means of a specialized remote equation is shown. [ABSTRACT FROM AUTHOR]

Centralized control, which can overcome the ill interactional effects among decentralized controllers, impels a real need for fast and reliable computational algorithms to improve the accuracy of phasor and power measurements. This paper deals with discrete Fourier transform (DFT)-based measurement techniques. Based on the practical frequency tracking method proposed by the same authors in another paper, this paper develops practical compensation method to improve the phasor and power measurement accuracy of the DFT algorithm. The method proposed by this paper takes full advantage of the DFT algorithm. It simply modifies the DFT results. With notable accuracy improvement, the calculation burden of the proposed method is little more than the DFT algorithm. The method can be used for on-line purposes. Though the analog signal studied in this paper is sinusoidal signal, the method proposed by this paper has good performance in the presence of harmonics. Some examples are given to demonstrate the feasibility, simpleness and robustness of the proposed method. [ABSTRACT FROM AUTHOR]