Scheduled System Maintenance:
On May 6th, single article purchases and IEEE account management will be unavailable from 8:00 AM - 12:00 PM ET (12:00 - 16:00 UTC). We apologize for the inconvenience.
By Topic

Energy Conversion, IEEE Transactions on

Issue 4 • Date Dec. 2007

Filter Results

Displaying Results 1 - 18 of 18
  • Table of contents

    Publication Year: 2007 , Page(s): C1
    Save to Project icon | Request Permissions | PDF file iconPDF (32 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Energy Conversion publication information

    Publication Year: 2007 , Page(s): C2
    Save to Project icon | Request Permissions | PDF file iconPDF (39 KB)  
    Freely Available from IEEE
  • Two-Step Method for Identification of Nonlinear Model of Induction Machine

    Publication Year: 2007 , Page(s): 801 - 809
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (564 KB) |  | HTML iconHTML  

    A two-step method is applied for parameter identification of a saturated electromechanical model of an induction machine (IM). The k-factor cross saturation technique is used to account for iron saturation. Balanced and unbalanced short-circuits armature current waveforms of this machine are less sensitive to variations in the mechanical parameters. Conversely, any change in these parameters has a strong impact on the start-up test. Accordingly, in the proposed estimation method, the online double-line-to-neutral short-circuit test is performed to estimate the electrical parameters of the machine and the results obtained are then used to compute the mechanical parameters from the starting test. The good agreement of the estimated results with actual data attests to the effectiveness and suitability of the proposed algorithm in computing the electromechanical parameters of these machines. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Online and Offline Rotary Regression Analysis of Torque Estimator for Switched Reluctance Motor Drives

    Publication Year: 2007 , Page(s): 810 - 818
    Cited by:  Papers (7)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (285 KB) |  | HTML iconHTML  

    A new torque estimator for switched reluctance motor (SRM) drives based on 2-D rotary regression analysis is presented in this paper. The proposed torque estimator is composed of a bicubic regressive polynomial as a function of rotor position and input current. The regressive coefficients can be computed offline or online from the torque characteristics acquired either experimentally or from numerical computation. Furthermore, a torque estimation method by taking mutual coupling into consideration is proposed. It can be seen that the estimated and experimentally obtained self-coupling and mutual-coupling torque characteristics are in good agreement with each other. In addition, the dynamic torque waveforms with and without the mutual coupling, estimated by the proposed estimator, are found to be virtually the same as those obtained from the bicubic spline interpolation for SRM drives with single-pulse voltage, hysteresis current chopping, as well as with voltage pulse width modulation control. The success of all the case studies being reported is a good validation of the usefulness and accuracy of the proposed real-time torque estimator that, as described in this paper, can be used to quickly estimate the instantaneous output torque of SRM drives. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Modeling of Saturated Induction Machines With Injected High-Frequency Signals

    Publication Year: 2007 , Page(s): 819 - 828
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1118 KB) |  | HTML iconHTML  

    This paper analyzes the effects of injecting additional signals in induction machines for the purpose of speed control. A new saturation model able to correctly model the interaction between the added signal and saturation of the motor core due to the main torque-producing flux is presented. The introduction of a variable saturation factor is used to model the variation of the saturation level due to the additional signal. A third harmonic rotor circuit is also introduced to take account of the third harmonic component of the air-gap flux, due to saturation. An additional balanced voltage set is added to the normal supply to analyze the effects of such signals on a saturated induction motor. Simulation results of such a model both at no load and full load are presented together with experimental measurements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Direct Instantaneous Torque Control in Direct Drive Permanent Magnet Synchronous Motors—a New Approach

    Publication Year: 2007 , Page(s): 829 - 838
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (592 KB)  

    In this paper, a novel direct instantaneous torque control scheme for a direct drive (DD) permanent magnet synchronous motor (PMSM) is presented. A hybrid control structure combining the internal model principle and the variable structure control (VSC) approach is proposed. First, a variable structure torque controller is adopted to regulate the torque angle increment according to the torque feedback error. Second, the appropriate control voltage vector is determined using the reference stator flux vector and the estimated dynamic back electromotive force (EMF) vector, as an internal model, in a deadbeat control manner. Subsequently, better disturbance rejection can be obtained with the proposed cascaded control structure. To robustly obtain the instantaneous torque and flux information, a robust adaptive motor model is proposed. The Lyapunov stability theory is used to analyze the stability of the augmented robust adaptive motor model and to give a guideline for tuning model parameters. Experimental results are presented to demonstrate the validity and effectiveness of the proposed instantaneous torque control scheme. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Position Stepping Method for Predicting Performances of Switched Reluctance Motor Drives

    Publication Year: 2007 , Page(s): 839 - 847
    Cited by:  Papers (4)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (298 KB) |  | HTML iconHTML  

    This paper presents a novel numerical method, which will be referred as the position stepping method (PSM), to predict the performances of switched reluctance motor (SRM) drives. The 2D bicubic spline is employed to generate the finite rectangular elements. The 2D bilinear spline is used to model the nonlinear magnetic characteristics in SRMs. Consequently, the conventional nonlinear first-order differential voltage equation for describing the performances of SRM drives can be simplified into an analytical expression in terms of the current with respect to the rotor position. Furthermore, the position stepping algorithm is developed according to the boundary and continuity conditions, to accurately and rapidly compute the current from the proposed current expression. Simulated and measured current waveforms are reported to validate the developed PSM. The CPU execution time required by the PSM compares very favorably with that of the analytical method. Overall, this paper provides an accurate and speedy approach to predict the currents and torques of SRM drives. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Novel High-Efficiency Battery Charger With a Buck Zero-Voltage-Switching Resonant Converter

    Publication Year: 2007 , Page(s): 848 - 854
    Cited by:  Papers (27)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (435 KB) |  | HTML iconHTML  

    The high-frequency resonant converter has numerous well-known advantages over the traditional hard-switching converters. The most important advantage is that it offers a lower switching loss and a higher power density. Additionally, the soft-switching current waveform characterizes a lower electromagnetic interference (EMI). This study presents the circuit configuration with the least components to realize a highly efficient solar energy battery charger with a zero-voltage-switching resonant converter. The optimal values of the resonant components are determined by applying the characteristic curve and the electric functions derived from the circuit configuration. The experiment demonstrates the switching on and off of the main switches in a solar energy battery charger with a zero-voltage-switching resonant converter, wherein the switches are all operated using zero-voltage switching. The circuit efficiency in the overall charging process exceeds 80%. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Approach to Fault-Tolerant Three-Phase Matrix Converter Drives

    Publication Year: 2007 , Page(s): 855 - 863
    Cited by:  Papers (37)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (549 KB) |  | HTML iconHTML  

    Despite numerous research efforts in matrix converter-based drives, a study of fault-tolerant topology and control strategy for a matrix converter drive has not been presented in the literature. This paper proposes a matrix converter structure and a modulation technique for the remedial operation in case of opened switch faults and single-phase open circuits. The fault compensation is achieved by reconfiguring the matrix converter topology with the help of a connecting device. Based on the redefined converter structure, a fault-tolerant modulation algorithm is developed to reshape output currents of two unfaulty phases for obtaining continuous operation. The proposed method allows improved system reliability and fault-tolerant capability with no backup leg and no parallel redundancy. Simulation and experimental results are shown to demonstrate the feasibility of the proposed fault-tolerant approach to the matrix converter drives. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Load Transient Mitigation for Stand-Alone Fuel Cell Power Generation Systems

    Publication Year: 2007 , Page(s): 864 - 872
    Cited by:  Papers (30)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (627 KB) |  | HTML iconHTML  

    In this paper, a load transient mitigation technique for stand-alone fuel cell (FC)-battery power generation systems is proposed. The technique can be used not only to improve the output power quality of the overall system, but also to mitigate or eliminate the electrical feedback stresses that are caused by load transients upon fuel cells. As a result, the durability of the fuel cell can also be improved. System analysis and controller design procedure for the proposed technique are given in this paper. Simulation studies have been carried out on FC-battery power generation systems using the dynamic models developed for proton exchange membrane fuel cell (PEMFC) and solid-oxide fuel cell (SOFC). Simulation results show the effectiveness of the proposed technique in preventing load transients from affecting the fuel cell performance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Soft-Computing Model-Based Controllers for Increased Photovoltaic Plant Efficiencies

    Publication Year: 2007 , Page(s): 873 - 880
    Cited by:  Papers (13)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (425 KB) |  | HTML iconHTML  

    Improved solar cell models and control methods using synergies of soft-computing techniques are used to demonstrate increased energy efficiencies of photovoltaic (PV) power plants connected to the electricity grid via space-vector-modulated three-phase inverters. The models and control strategies are combined to form two new model-based controllers that are more accurate and resilient than existing solutions resulting in increased power production. A radial-basis-function-network (RBFN) model with a neuro-fuzzy regulator applied to a plant well characterized by the conventional solar cell model provided an estimated 1.5% increase in power production over an existing conventional model proportional integral (PI)-regulator combination. A neuro-fuzzy model with a neuro-fuzzy controller applied to a plant poorly characterized by the conventional solar cell model gave an 8.6% increase in power. An analysis of the net contributions to the increased efficiencies shows that the improved models had the most effect on power gains. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Single-Stage Three-Phase Grid-Connected Photovoltaic System With Modified MPPT Method and Reactive Power Compensation

    Publication Year: 2007 , Page(s): 881 - 886
    Cited by:  Papers (73)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (307 KB) |  | HTML iconHTML  

    Single-stage grid-connected photovoltaic (PV) systems have advantages such as simple topology, high efficiency, etc. However, since all the control objectives such as the maximum power point tracking (MPPT), synchronization with the utility voltage, and harmonics reduction for output current need to be considered simultaneously, the complexity of the control scheme is much increased. This paper presents the implementation of a single-stage three-phase grid-connected PV system. In addition to realize the aforementioned control objectives, the proposed control can also remarkably improve the stability of the MPPT method with a modified incremental conductance MPPT method. The reactive power compensation for local load is also realized, so as to alleviate grid burden. A DSP is employed to implement the proposed MPPT controller and reactive power compensation unit. Simulation and experimental results show the high stability and high efficiency of this single-stage three-phase grid-connected PV system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Physically Based Dynamic Model for Solid Oxide Fuel Cells

    Publication Year: 2007 , Page(s): 887 - 897
    Cited by:  Papers (38)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (450 KB) |  | HTML iconHTML  

    This paper presents a physically based dynamic model for tubular solid oxide fuel cells (SOFCs) based on the electrochemical and thermodynamic characteristics inside SOFC. The diffusion, material conservation, electrochemical, and thermodynamic equations are used to develop the SOFC model. The effect of temperature on the steady-state (V-I and P-I) characteristics of the SOFC model has been studied, and the model responses have been obtained for constant fuel flow as well as for constant fuel utilization operating modes. The dynamic characteristics of the model are investigated in small, medium, and large timescales, from milliseconds to minutes. The model has been implemented in MATLAB/Simulink and used to investigate the distributed generation applications of SOFCs. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Short-Time Overloading Capability and Distributed Generation Applications of Solid Oxide Fuel Cells

    Publication Year: 2007 , Page(s): 898 - 906
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (552 KB) |  | HTML iconHTML  

    This paper presents some application studies of the dynamic solid oxide fuel cell (SOFC) model developed by the authors and reported in C. Wang and M. H. Nehrir, ldquoA physically-based dynamic model for solid oxide fuel cells,rdquo IEEE Trans. Energy Convers. First, the model is used to investigate the short-time overloading capability of the SOFC. Then, the application of the model in distributed generation (DG) system studies is explored. Controller design methodologies are also presented for grid-connected SOFC DG power conditioning units to control power flow from the SOFC DG to the utility grid. Simulation results show that the SOFC DG system is able to manage real and reactive power flows to the utility grid to which it is connected. They also show that a properly designed SOFC DG can remain stable under temporary electrical faults. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • IEEE copyright form

    Publication Year: 2007 , Page(s): 907 - 908
    Save to Project icon | Request Permissions | PDF file iconPDF (1057 KB)  
    Freely Available from IEEE
  • 2007 Index IEEE Transactions on Energy Conversion Vol. 22

    Publication Year: 2007 , Page(s): 909 - 924
    Save to Project icon | Request Permissions | PDF file iconPDF (175 KB)  
    Freely Available from IEEE
  • IEEE Power Engineering Society Information for authors

    Publication Year: 2007 , Page(s): C3
    Save to Project icon | Request Permissions | PDF file iconPDF (32 KB)  
    Freely Available from IEEE
  • Blank page [back cover]

    Publication Year: 2007 , Page(s): C4
    Save to Project icon | Request Permissions | PDF file iconPDF (1 KB)  
    Freely Available from IEEE

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