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Energy Conversion, IEEE Transactions on

Issue 3 • Date Sept. 2013

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Displaying Results 1 - 25 of 37
  • Table of contents

    Publication Year: 2013 , Page(s): C1 - C4
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    Freely Available from IEEE
  • IEEE Transactions on Energy Conversion publication information

    Publication Year: 2013 , Page(s): C2
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    Freely Available from IEEE
  • No-Load Voltage Waveform Optimization and Damper Bars Heat Reduction of Tubular Hydrogenerator by Different Degree of Adjusting Damper Bar Pitch and Skewing Stator Slot

    Publication Year: 2013 , Page(s): 461 - 469
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (971 KB) |  | HTML iconHTML  

    To analyze the influence of no-load voltage waveforms and damper bar losses and heat by the damper bar pitch and stator slot skew, finite-element model (FEM) computations are conducted. The calculation models are multislice moving electromagnetic field-circuit coupling model for the hydrogenerator and three-dimensional temperature field FEM for the rotor. This analysis considers the factors such as the rotor motion and the nonlinearity of time-varying electromagnetic field, the anisotropic heat conduction of the rotor core lamination, and the different heat dissipation conditions on the windward and the leeward sides of the poles. Then, the no-load voltage waveforms of a 36 MW tubular hydrogenerator are optimized and the damper bar heat at the rated load is reduced with the design scheme by adjusting the damper bar pitch and the stator slot skew. The results show that the waveforms of the no-load voltage are improved and the temperature of damper bars are reduced when reasonably increasing damper bar pitch and skewing stator slots. The calculated results are well coincident with the test data. The research is helpful for improving the design standard and enhancing the operation reliability of the large tubular hydrogenerator and electric network. View full abstract»

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  • Data-Driven Modeling and Predictive Control for Boiler–Turbine Unit

    Publication Year: 2013 , Page(s): 470 - 481
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (949 KB) |  | HTML iconHTML  

    This paper develops a novel data-driven modeling strategy and predictive controller for boiler-turbine unit using subspace identification and multimodel method. To deal with the nonlinear behavior of boiler-turbine unit, the system is divided into a number of local regions following the analysis of the nonlinearity distribution along the operation range, and then the corresponding measurement data are organized to identify the local models through the subspace method. By transforming local models into the same basis, the resulting multimodel system (MMS) is shown to represent the boiler-turbine unit very closely, and thus, used in designing a multimodel-based model predictive control (MMPC). As an alternative approach, a data-driven direct predictive controller (DDPC) is developed by utilizing the intermediate subspace matrices as local predictors. Online update of the predictor is also implemented on the multimodel structure to make the controller responsive to plant behavior variations. Simulation results demonstrate the feasibility and effectiveness of the proposed approach. View full abstract»

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  • Electromagnetic Energy Conversion Efficiency Enhancement of Switched Reluctance Motors With Zero-Voltage Loop Current Commutation

    Publication Year: 2013 , Page(s): 482 - 492
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1286 KB) |  | HTML iconHTML  

    Zero-voltage loop (ZVL) commutation in switched reluctance (SR) motor operation can result in a significant improvement of their performance by lowering the flux-linkage peaks and harmonic magnitudes of the magnetic flux densities within the core of the SR motor. The efficiency enhancement provided by ZVL commutation, especially in high-speed SR motoring has not been thoroughly investigated to-date. This paper investigates the energy conversion efficiency of SR motors with ZVL current commutation. The lowering of core losses is investigated with finite element modeling of a 250 kW 12/8 SR motor. An enhancement of efficiency in the ranges of 0--3% and 0--5% is computed considering operation below base-speed and above base-speed respectively. The effect of core material on the ZVL commutation performance is also investigated for the 250 kW 12/8 SR motor. The increase of efficiency with ZVL is further validated with experimental results on a 300 W 6/4 SR motor which achieves an enhancement in the range of 2-6%. View full abstract»

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  • Split Ratio Optimization for High-Torque PM Motors Considering Global and Local Thermal Limitations

    Publication Year: 2013 , Page(s): 493 - 501
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (850 KB) |  | HTML iconHTML  

    The split ratio of an interior rotor permanent-magnet machine, which relates the rotor diameter to the total motor diameter, can be optimized with the goal of generating maximum torque for a given motor volume. For that purpose, thermal constraints have to be considered that limit the producible magnetomotive force and, consequently, the torque output. Both a maximum local current density in the coils and a maximum global copper loss density related to the motor surface are respected. In this paper, the analytical calculations for torque and split ratio are derived and the influence of these thermal constraints is elaborated. View full abstract»

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  • Asymmetrical Low-Voltage Ride Through of Brushless Doubly Fed Induction Generators for the Wind Power Generation

    Publication Year: 2013 , Page(s): 502 - 511
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1994 KB) |  | HTML iconHTML  

    Compared with the Doubly fed induction generators (DFIG), the brushless doubly fed induction generator (BDFIG) has a commercial potential for wind power generation due to its lower cost and higher reliability. In the most recent grid codes, wind generators are required to be capable of riding through low voltage faults. As a result of the negative sequence, induction generators response differently in asymmetrical voltage dips compared with the symmetrical dip. This paper gave a full behavior analysis of the BDFIG under different types of the asymmetrical fault and proposed a novel control strategy for the BDFIG to ride through asymmetrical low voltage dips without any extra hardware such as crowbars. The proposed control strategies are experimentally verified by a 250-kW BDFIG. View full abstract»

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  • A Novel Cascaded Boost Chopper for the Wind Energy Conversion System Based on the Permanent Magnet Synchronous Generator

    Publication Year: 2013 , Page(s): 512 - 522
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (9589 KB) |  | HTML iconHTML  

    In the wind energy conversion system (WECS) based on the permanent magnet synchronous generator, the topology that a wind generator is connected to a voltage source inverter through a diode rectifier and a boost chopper is widely adopted for its low cost and high reliability. However, with the increasing power level of the WECS, the power switch device of a boost chopper in the topology has to endure high instantaneous voltage and current stress, thus reducing the system reliability. Although the traditional multiple boost converter reduces the transmission power level of single circuit units in terms of structure, it is still limited by narrow speed regulation range. Thus, a novel switchable-cascaded-mode boost chopper is proposed in this paper. The operation principle of the new converter and the generator speed control strategy are analyzed. At last, the effectiveness of the new converter is verified with an experimental prototype. The experimental results demonstrate that speed range is extended by using the new topology as generator-side converter in the permanent magnet wind generation system. View full abstract»

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  • Stator Winding Connection-Mode Management in Line-Start Permanent Magnet Motors to Improve Their Efficiency and Power Factor

    Publication Year: 2013 , Page(s): 523 - 534
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2316 KB) |  | HTML iconHTML  

    Three-phase line-start permanent magnet motors (LSPMs) are a recent entrance in the marketplace. In general, such motors are designed to meet IE4/Super-Premium Class requirements. As with squirrel-cage induction motors, LSPMs can benefit in terms of efficiency and power factor from a proper magnetizing flux adjustment as a function of their load. This is important to improve the motor performance when it is oversized and/or driving variable-load fixed-speed applications. In this paper, an experimental study on the improvement potential of steady-state partial-load efficiency and power factor in special multiconnection LSPMs with up to six different flux levels is presented. Some novel conclusions are offered regarding the efficiency and power factor gains and connection-mode management as a function of motor actual load, including the delta-star change in conventional six-terminal LSPMs. With the proposed solution, efficiency gains of 6-8% points and power factor gains of 0.4-0.5 points can be obtained in LSPMs at light partial loads, representing a very significant performance improvement. Moreover, it is demonstrated that reactive power injection into the mains grid is possible with LSPMs. View full abstract»

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  • Evaluation of the Performance of a DC-Link Brake Chopper as a DFIG Low-Voltage Fault-Ride-Through Device

    Publication Year: 2013 , Page(s): 535 - 542
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (911 KB) |  | HTML iconHTML  

    The performance of the doubly fed induction generator (DFIG) during grid faults is attracting much interest due to the proliferation of wind turbines that employ this technology. International grid codes specify that the generator must exhibit a fault-ride-through (FRT) capability by remaining connected and contributing to network stability during a fault. Many DFIG systems employ a rotor circuit crowbar to protect the rotor converter during a fault. Although this works well to protect the generator, it does not provide favorable grid support behavior. This paper describes an experimental investigation of an alternative FRT approach using a brake chopper circuit across the converter dc link to ensure that the dc-link voltage remains under control during a fault. Two different approaches to chopper control are examined and the resulting FRT performance is compared with that of a conventional crowbar approach. The new chopper-based control methods are experimentally evaluated using a 7.5-kW DFIG test rig facility. View full abstract»

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  • Optimal Design of Adjustable Air-Gap, Two-Speed, Capacitor-Run, Single-Phase Axial Flux Induction Motors

    Publication Year: 2013 , Page(s): 543 - 552
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1022 KB) |  | HTML iconHTML  

    -In this paper, a new optimized structure for two-speed, capacitor-run, single-phase axial flux induction motor (AFIM) for direct-drive operation is presented. Although, there are many advantages for direct-drive systems, their axial forces between the stator and rotor increases with reduction in air-gap length and is of serious concern. An increase in the air-gap length will result in the deterioration of performance characteristics of the motor. In this paper, a new construction technique is proposed to fabricate an AFIM with adjustable air-gap length. After presenting a comprehensive design algorithm, all geometrical dimensions and electrical equivalent circuit parameters are analytically calculated. Then, a multiobjective and multivariable optimization for a high efficiency and power factor with minimum usage of core materials is carried out. Optimization process is verified using three-dimensional, time-stepping finite-element analyses, and finally, the prototype of the optimal motor is fabricated and tested. Good agreements between analytic, finite element, and experimental results show the success of the proposed design. View full abstract»

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  • Efficiency Optimization in Low Inertia Wells Turbine-Oscillating Water Column Devices

    Publication Year: 2013 , Page(s): 553 - 564
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1043 KB) |  | HTML iconHTML  

    The Wells turbine is a bidirectional air turbine which operates efficiently over a restricted range of air flow. The optimization of its efficiency requires control of rotational velocity in order to maintain the ratio between airflow and tip speed within the high efficiency range. This paper introduces two generator control strategies that optimize the power take-off efficiency for low inertia turbine systems in which instantaneous control of the turbine air flow to tip speed ratio is a realistic goal. The first control strategy requires measurement of turbine rotational speed and air chamber pressure, and the second strategy removes the requirement for air pressure measurement. The implementation issues associated with this level of control are examined and the simulation results are validated in an experimental test rig. View full abstract»

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  • A Fast PV Power Tracking Control Algorithm With Reduced Power Mode

    Publication Year: 2013 , Page(s): 565 - 575
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1687 KB) |  | HTML iconHTML  

    This paper presents a fast maximum power point tracking (MPPT) control algorithm for the photovoltaic (PV) in a hybrid wind-PV system, in which the PV generatormay also need to work in a reduced power mode (RPM) to avoid dynamic overloading. The two control modes, MPPT and RPM, are inherently compatible and can be readily implemented, without the need of a dumping load for the RPM. Following the establishment of a dynamic system model, the study develops the guidelines to determine the variables of a direct hill-climbing method for MPPT: the perturbation time intervals and the magnitudes of the applied perturbations. These results are then used to optimally set up a variable-step size incremental conductance (VSIC) algorithm along with adaptive RPM control. The power tracking performance and power limiting capability are verified by simulation and experiment. View full abstract»

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  • A Voltage-Behind-Reactance Model of Five-Phase Induction Machines Considering the Effect of Magnetic Saturation

    Publication Year: 2013 , Page(s): 576 - 592
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1802 KB) |  | HTML iconHTML  

    Five-phase induction machines are generally modeled using multiple dq planes or using a phase variable model. This paper considers modeling five-phase induction machines using a voltage-behind-reactance (VBR) configuration. This configuration lends itself suitable for time-domain circuit-based simulators as the MATLAB/Simulink SimPowerSystems (SPS) toolbox. The stator electrical dynamics are represented in five-phase coordinates, while the rotor electrical circuit is modeled using rotor flux linkage as the state variable and expressed in the dq stator reference frame. The VBR model is equivalent to a conventional dq model; however, it facilitates the connection of an external inductance without affecting numerical accuracy and calculation efficiency. It also facilitates the simulation of different winding connections, series-connected multimotors, and open phase(s) conditions. The model is, first, derived for a magnetically linear system and then it is extended to include the effect of magnetic saturation. The flux correction method is used to represent the effect of magnetic saturation with a simple modification to represent the effect of cross coupling between fundamental and third sequence planes due to saturation effect. The dynamic cross saturation is considered by adding compensating terms that depend on magnetizing inductance variation. The proposed model is experimentally verified using a prototype 1.5-hp five-phase induction machine under different operating conditions. View full abstract»

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  • Artificial Inductance Concept to Compensate Nonlinear Inductance Effects in the Back EMF-Based Sensorless Control Method for PMSM

    Publication Year: 2013 , Page(s): 593 - 600
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1051 KB) |  | HTML iconHTML  

    The back EMF-based sensorless control method is very popular for permanent magnet synchronous machines (PMSMs) in the medium- to high-speed operation range due to its simple structure. In this speed range, the accuracy of the estimated position is mainly affected by the inductance, which varies at different loading conditions due to saturation effects. In this paper, a new concept of using a constant artificial inductance to replace the actual varying machine inductance for position estimation is introduced. This facilitates greatly the analysis of the influence of inductance variation on the estimated position error, and gives a deep insight into this problem. It also provides a simple approach to achieve a globally minimized position error. A proper choice of the artificial machine inductance may reduce the maximum position error by 50% without considering the actual inductance variation in the control algorithm. Analytical and experimental results are given for validating the proposed theory. View full abstract»

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  • A Flexible AC Distribution System Device for a Microgrid

    Publication Year: 2013 , Page(s): 601 - 610
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1974 KB) |  | HTML iconHTML  

    This paper presents a flexible ac distribution system device for microgrid applications. The device aims to improve the power quality and reliability of the overall power distribution system that the microgrid is connected to. The control design employs a new model predictive control algorithm which allows faster computational time for large power systems by optimizing the steady-state and the transient control problems separately. Extended Kalman filters are also employed for frequency tracking and to extract the harmonic spectra of the grid voltage and the load currents in the microgrid. The design concept is verified through different test case scenarios to demonstrate the capability of the proposed device and the results obtained are discussed. View full abstract»

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  • A New Time-Step Method for Machine Drive Analysis by Strong Coupling Magnetic Field With the External Circuit and Control Algorithm

    Publication Year: 2013 , Page(s): 611 - 618
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (878 KB) |  | HTML iconHTML  

    Electric machine drive system analysis by strong coupling magnetic field with the nonlinear external circuit and control algorithm is increasingly drawing attentions from both the academic researchers and industrial designers. The steady and transient performances of the drive system can be accordingly obtained with credible computation convergence and accuracy by taking into account the space harmonics, time harmonics, and their interactions between. However, the pulse-width modulation techniques commonly employed in the electric machine drives will normally result in numeric analysis with extensive computational time. A novel time-step method, namely trigger method, is proposed in order to reduce the computational load in this paper. The comparisons between the results from the conventional and new methods have revealed that the proposed method could significantly reduce the simulation time without notable compromise on the accuracy. Experimental tests of a permanent magnet synchronous machine drive system with the space vector pulse width modulation technique are carried out to validate the simulation results from the proposed method. Besides, the validity of the proposed trigger method has been further underpinned by the corresponding estimated and experimental results of a practical servo-drive system based on the synchronous reluctance machine. View full abstract»

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  • Implemental Control Strategy for Grid Stabilization of Grid-Connected PV System Based on German Grid Code in Symmetrical Low-to-Medium Voltage Network

    Publication Year: 2013 , Page(s): 619 - 631
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3893 KB) |  | HTML iconHTML  

    In the last couple of years, the increasing penetration of renewable energy resulted in the development of grid-connected large-scale power plants. However, a high penetration harbors the risk of grid instability if the generating power plants are not able to support the grid. Therefore, grid stabilization, which depends on the system-type or grid of each country, plays an important role and has been strengthened by different grid codes. With this background, VDE-AR-N 4105 for photovoltaic (PV) systems connected to the low-voltage grid and the German Association of Energy and Water Industries (BDEW) introduced the medium-voltage grid code for connecting power plants to the grid and they are the most stringent certifications. In this paper, the control strategy of generating system is enhanced with VDE-AR-N 4105 and BDEW grid code, where both active/reactive powers are controlled. Simulation and experimental results of 100-kW PV inverter are shown to verify the effectiveness of the proposed implemental control strategy. View full abstract»

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  • A Novel Wind Power Generator System with Automatic Maximum Power Tracking Capability

    Publication Year: 2013 , Page(s): 632 - 642
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1383 KB) |  | HTML iconHTML  

    This paper presents a novel off-grid wind power generator system that consists of a permanent magnet (PM) generator, two rectifiers, a battery, and loads. The PM generator has a novel stator structure and two Y-connected winding sets. The wind power generator system can automatically track the maximum power from wind without the need for converters and control circuits, and has higher reliability and lower loss. This paper also describes the operational principle and mathematical model of the system. A prototype is manufactured, and experiments prove that the new system efficiently captures maximum power from wind across a wide speed range. View full abstract»

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  • Integrating Hybrid Power Source Into an Islanded MV Microgrid Using CHB Multilevel Inverter Under Unbalanced and Nonlinear Load Conditions

    Publication Year: 2013 , Page(s): 643 - 651
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2103 KB) |  | HTML iconHTML  

    This paper presents a control strategy for an islanded medium voltage microgrid to coordinate hybrid power source (HPS) units and to control interfaced multilevel inverters under unbalanced and nonlinear load conditions. The proposed HPS systems are connected to the loads through a cascaded H-bridge (CHB) multilevel inverter. The CHB multilevel inverters increase the output voltage level and enhance power quality. The HPS employs fuel cell (FC) and photovoltaic sources as the main and supercapacitors as the complementary power sources. Fast transient response, high performance, high power density, and low FC fuel consumption are the main advantages of the proposed HPS system. The proposed control strategy consists of a power management unit for the HPS system and a voltage controller for the CHB multilevel inverter. Each distributed generation unit employs a multiproportional resonant controller to regulate the buses voltages even when the loads are unbalanced and/or nonlinear. Digital time-domain simulation studies are carried out in the PSCAD/EMTDC environment to verify the performance of the overall proposed control system. View full abstract»

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  • Multi-Objective Model-Predictive Control for High-Power Converters

    Publication Year: 2013 , Page(s): 652 - 663
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1738 KB) |  | HTML iconHTML  

    This paper presents a multi-objective model-predictive control (MOMPC) strategy for controlling converters in high-power applications. The controller uses the system model to predict the system behavior in each sampling interval for each voltage vector, and the most appropriate vector is then chosen according to an optimization criterion. By changing the cost function properly, multiobjectives can be achieved. To eliminate the influences of one step delay in digital implementation, a model-based prediction scheme is introduced. For high-power applications, the converter switching frequency is normally kept low in order to reduce the switching losses; this is done by adding a nonlinear constraint in the cost function. However, to avoid system stability deterioration caused by the low switching frequency, an N-step horizontal prediction is proposed. Finally, the control algorithm is simplified using a graphical algorithm to reduce the computational burden. The proposed MOMPC strategy was verified numerically by using MATLAB/Simulink, and validated experimentally using a laboratory ac/dc converter. View full abstract»

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  • Comparison of Cogging Torque Reduction in Permanent Magnet Brushless Machines by Conventional and Herringbone Skewing Techniques

    Publication Year: 2013 , Page(s): 664 - 674
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1607 KB) |  | HTML iconHTML  

    Cogging torque, as one of the main parasitic demerits of permanent magnet brushless machines, is of particular importance and primary concern during the machine design stage in many high-performance applications. Hence, numerous design techniques have been proposed and employed to effectively alleviate the cogging torque in permanent magnet brushless machines. The effects of rotor step skewing techniques including both conventional and herringbone styles on the cogging torque of permanent magnet brushless machine are comprehensively investigated and compared by synthesized 2-D and 3-D finite-element analysis in this paper. The results have revealed that both the conventional and herringbone rotor step skewing techniques can reduce the cogging torque significantly, but the latter is less effective than the former especially with small skewing step numbers. Moreover, the machine with herringbone rotor step skewing technique has rather peculiar and asymmetric cogging torque profiles, while the machine with conventional rotor step skewing technique exhibits normal and symmetric ones. The validity of the obtained results and findings is underpinned by the experiments on the prototype machine. View full abstract»

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  • Advancements in OCV Measurement and Analysis for Lithium-Ion Batteries

    Publication Year: 2013 , Page(s): 675 - 681
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (689 KB) |  | HTML iconHTML  

    Incremental open-circuit voltage (OCV) curves and low-current charge/discharge voltage profiles of a lithium-ion (Li-ion) battery are compared and evaluated for optimizing measurement time and resolution. Since these curves are often used for further analysis, minimizing kinetic contributions is crucial for approximating battery OCV behavior. In this context, an incremental OCV measurement is characterized by state of charge (SOC) intervals and relaxation times. Various constant low C-rates, SOC intervals, and relaxation times are tested for approximating OCV behavior. Differential capacity and voltage analysis is used to check whether the main electrode features can be resolved satisfactorily. An interpolation method yields additional data points for the differential analysis of incremental OCV curves. It is shown that incremental OCV measurements are suitable for an approximation of battery OCV behavior, rather than low current-voltage profiles. Furthermore, extrapolation of voltage relaxation enables the estimation of fully relaxed OCV. View full abstract»

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  • Active and Reactive Power Control for Wind Turbine Based on a MIMO 2-Sliding Mode Algorithm With Variable Gains

    Publication Year: 2013 , Page(s): 682 - 689
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1653 KB) |  | HTML iconHTML  

    This study proposes a power control strategy for a grid-connected variable-speed wind turbine, based on a doubly-fed induction generator (DFIG) with slip power recovery. The control objectives vary with the zones of operation (dependant on the wind speed), aiming to maximize the active power in the partial load zone and to limit it when operating within the full load zone, while regulating the stator reactive power following grid requirements. The control design, based on the second-order sliding modes (SOSM) and Lyapunov, uses a modified version of the super-twisting algorithm with variable gains which can be applied to nonlinear multiple inputs-multiple outputs (MIMO) systems. The well-known robustness of the sliding techniques, the simplicity of the algorithm, and the adaptive characteristic of its gains are used together in this study to obtain a controller able to deal robustly with the exacting challenges presented by these systems. An additional benefit of the proposal lies in the smoothness of the control action, an important issue regarding applied mechanical efforts. Representative results obtained by simulation of the controlled system are shown and discussed. View full abstract»

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  • Control of a Supercapacitor Energy Storage System for Microgrid Applications

    Publication Year: 2013 , Page(s): 690 - 697
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1531 KB) |  | HTML iconHTML  

    The proper operation of a microgrid requires storage devices that increase the inertia and avoid instability of the system. This paper presents the control of an energy storage system (ESS) based on supercapacitor in the context of grid-connected microgrids. The ESS is composed of AC/DC and DC/DC converters tied by a dc link. A single sliding mode strategy is proposed to control a bidirectional dc/dc converter, capable of working properly under all operating conditions. The switching devices are commanded by a single sliding function, dynamically shaped by references sent from the microgrid central controller. This feature facilitates the implementation and design of the control law and simplifies the stability analysis over the entire operating range. The effectiveness of the proposed control strategy is illustrated by experimental results. View full abstract»

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Aims & Scope

The IEEE Transactions on Energy Conversion includes in its venue the research, development, design, application, construction, installation, operation, analysis and control of electric power generating and energy storage equipment (along with conventional, cogeneration, nuclear, distributed or renewable sources, central station and grid connection). The scope also includes electromechanical energy conversion, electric machinery, devices, systems and facilities for the safe, reliable, and economic generation and utilization of electrical energy for general industrial, commercial, public, and domestic consumption of electrical energy.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Juri Jatskevich
University of British Columbia