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Early Access Articles

Early Access articles are new content made available in advance of the final electronic or print versions and result from IEEE's Preprint or Rapid Post processes. Preprint articles are peer-reviewed but not fully edited. Rapid Post articles are peer-reviewed and edited but not paginated. Both these types of Early Access articles are fully citable from the moment they appear in IEEE Xplore.

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Displaying Results 1 - 25 of 74
  • A Novel Variable Reluctance Resolver with Nonoverlapping Tooth–Coil Windings

    Page(s): 1 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1601 KB)  

    A novel variable reluctance (VR) resolver with nonoverlapping tooth–coil windings is proposed in this paper. It significantly simplifies the manufacturing process of multilayer windings in conventional products. Finite element (FE) analysis is used to illustrate the basic operating principle, followed by analytical derivation of main parameters and optimization of major dimensions, including air-gap length and slot opening width. Based on winding distributions and FE results, it is shown that identical stator and winding can be employed for a resolver with three different numbers of rotor poles. Further, other stator slot/rotor pole combinations based on the nonoverlapping tooth–coil windings are generalized. In addition, the influence of eccentricity and end-winding leakage on the proposed topology is investigated. Finally, a prototype is fabricated and tested to verify the analysis, including main parameters and electrical angle error. View full abstract»

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  • Real-Time Electrochemical Impedance Diagnosis for Fuel Cells Using a DC–DC Converter

    Page(s): 1 - 7
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (875 KB)  

    A multiport bidirectional dc–dc converter with a diagnosis function for fuel cells that employs electrochemical impedance analysis was developed. The proposed converter, which is connected to electric double layer capacitors, can freely adjust the fuel cell voltage without fluctuation of the load voltage. A signal that consists of multiple frequency sinusoidal waves is superimposed as a duty ratio signal of the chopper circuit connected to the fuel cell, which enables simultaneous impedance measurement for these frequencies. The voltage and current values of the fuel cell are acquired by a digital signal processor to conduct fast Fourier transform calculations that give voltage and current spectra. The fraction of the spectra yields the electrochemical impedance. Experiments were conducted to validate the proposed method using a polymer electrolyte membrane fuel cell. The sinusoidal waves in the imposed signal have multiple frequencies to reduce the measuring time. The impedance characteristics determined using the proposed method are in good agreement with those obtained with an electrochemical instrument. To demonstrate the proposed method, the Nyquist plots when the fuel cell current, the operation temperature, and the stoichiometric ratios were changed and produced using the proposed method. View full abstract»

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  • Comparison of Frequency and Time-Domain Iron and Magnet Loss Modeling Including PWM Harmonics in a PMSG for a Wind Energy Application

    Page(s): 1 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1130 KB)  

    This paper presents the calculation of the electromagnetic losses for a 2.1-MW permanent magnet synchronous generator for wind energy application. The focus is on recognizing the significance of including the analysis of higher harmonics in the electromagnetic loss calculation. The analyzed harmonics include the ones resulting from the use of a pulse width modulation (PWM) of the voltage of the generator. The magnet losses calculated for the PWM current are several times higher than the ones calculated for the sinusoidal current. In addition, frequency-domain and time-domain models for iron loss calculation are compared. The frequency-domain model that assumes a sinusoidal variation and considers only the fundamental component of the magnetic induction in the stator core material underestimates the iron losses in the machine. Especially, when the additional losses resulting from the higher harmonics, rotational fields, and minor loops are taken into account. Finally, it is shown how the composition and thickness of the electrical steel used in the stator core of the generator influences the total core losses. View full abstract»

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  • Convergence Analysis and Tuning of a Sliding-Mode Ripple-Correlation MPPT

    Page(s): 1 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1399 KB)  

    The development of fast maximum power point tracking (MPPT) algorithms for photovoltaic (PV) systems with high bandwidth and predictable response to irradiation transients is attractive for mobile applications and installations under fast changing weather conditions. This paper proposes the convergence analysis of a sliding-mode version of the MPPT based on ripple correlation control (RCC). The contribution of this paper is a dynamic model, useful to derive a set of design guidelines to tune the sliding-mode RCC-MPPT and achieve a desired dynamic performance under irradiation transients. The research is based on sliding control theory and it includes both the chattering phenomena analysis, and a discussion on the effects of reactive parasitic elements in the PV module. The proposed analysis and design have been validated by MATLAB simulations first, and then with experimental tests on a 35-W panel with a boost converter charging a 24-V battery. The results support the effectiveness of the proposed modeling procedure and design guidelines, showing good agreement between the model prediction and the experimental transient response. View full abstract»

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  • Incorporating Skew in a Magnetic Equivalent Circuit Model of Synchronous Machines

    Page(s): 1 - 3
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (529 KB)  

    In this letter, a multislice method has been extended to model skew in a magnetic equivalent circuit for wound rotor synchronous machines. Within the model, the machine is divided into a user-defined number of slices along its axial direction. A system of equations is derived in which the magnetic equivalent circuit (MEC) loop flux and the axial currents in each slice are unknowns. A constraint is used to enforce that the axial currents across all slices are equal. The method overcomes challenges of alternative approaches used to model skew in MECs that have been documented by the community. Hardware experiments are used to validate the approach. View full abstract»

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  • Effect of Multilevel Inverter Supply on Core Losses in Magnetic Materials and Electrical Machines

    Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (825 KB)  

    The effect of multilevel inverter supply on power losses in magnetic cores and electrical machines is studied. A dynamic numerical model for the hysteresis, eddy current, and excess losses in a core lamination is first developed. By both measurements and simulations for a ring-core inductor, we demonstrate how increasing the number of inverter voltage levels decreases the iron losses when compared with traditional two-level supply. Although the switching frequency has a significant impact on the iron losses in the case of a traditional two-level inverter, using three or five voltage levels makes the losses almost independent of the switching. Finally, finite-element simulations show that similar reductions are also possible for the core losses of 150-kVA and 12.5-MW wound-field synchronous machines, in which rather low switching frequencies are typically used. Calorimetric loss measurements are also presented for the 150-kVA machine in order to confirm the significant effect of switching frequency on the core losses with two-level inverter supply. View full abstract»

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  • A 12-Step Sensorless Drive for Brushless DC Motors Based on Back-EMF Differences

    Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (890 KB)  

    This paper presents a new 12-step sensorless drive for brushless dc motor based on back-electromotive force (back-EMF) differences, which are estimated from the disturbance observer (DOB) structure. Availability of rotor position information with a resolution of 30° and commutation without phase shift are the advantages of using the back-EMF differences. Unlike the conventional methods that obtain part of the back-EMF signal from the manipulation of three phase voltages, the proposed DOB structure can access the entire back-EMF profile. By designing a proper low-pass filter in the DOB structure, the back-EMF difference can be well detected with lower sensor noise. Compensation of delay commutation introduced by the filter is also discussed. Experiment results showed that the proposed sensorless drive is capable of running the motor in lower speed, and performs better under different speed and load torque as compared with the conventional method. View full abstract»

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  • A Vanadium-Redox-Flow-Battery Model for Evaluation of Distributed Storage Implementation in Residential Energy Systems

    Page(s): 1 - 10
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (669 KB)  

    A vanadium-redox-flow-battery (VRFB) model suitable for annual energy feasibility analyses of distributed storage implementation is presented in this paper. The validation of the proposed 6-kW/20-kWh VRFB semiempirical model, which takes into account auxiliary power consumption and operational aspects such as startup and standby behavior, is reported. The comparison between the simulation and the experimental results shows a good matching, quantified by the maximum root-mean-square deviation of the stack energy equal to 1.57% and 2.47% during charge and discharge, respectively. Moreover, the VRFB model is used in an application model of a residential building including a photovoltaic system and heat pump. Based on variation of control parameters, the energy efficiency for the proposed application has been maximized. Finally, a comparison with a scaled VRFB model (3 kW/10 kWh) is discussed with respect to the increase of the VRFB utilization and overall energy efficiency, confirming the effectiveness of the proposed model for distributed energy storage sizing and management in residential systems. View full abstract»

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  • Estimation of Stator Resistance in Direct Torque Control Synchronous Motor Drives

    Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1379 KB)  

    Direct torque control (DTC) is a high-performance method that provides effective control of stator flux modulus and electromagnetic torque of electric motors. However, error in estimation of stator resistance significantly degrades the performance of a DTC drive system, especially for a synchronous motor. This paper discusses the problems associated with the error in stator resistance and proposes an analytical approach to investigate its effect on the actual and estimated variables of a synchronous motor. Based on how this error affects the estimated angle between the stator flux and current vectors, a method to track stator resistance variations is proposed. The presented analytical method and the proposed stator resistance estimation are validated using simulation and experimental case studies. View full abstract»

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  • Reliability Comparison of Wind Turbines With DFIG and PMG Drive Trains

    Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1814 KB)  

    Modern wind turbines vary greatly in their drive train configurations. With the variety of options available, it can be difficult to determine which type is most suitable for on and offshore applications. A large percentage of modern drive trains consist of either doubly fed induction generators with partially rated converters or permanent magnet generators with fully rated converters. These configurations are the focus of this empirical reliability comparison. The turbine population for this analysis contains over 1800 doubly fed induction generators, partially rated converter wind turbines, and 400 permanent magnet generator fully rated converter wind turbines. The turbines analyzed are identical except for their drive train configurations and are modern MW scale turbines making this population the largest and most modern encountered in the literature review. Results of the analysis include overall failure rates, failure rates per operational year, failure rates per failure mode, and failure rates per failure cost category for the two drive train configurations. These results contribute toward deciding on the most suitable turbine type for a particular site, as well as toward cost of energy comparisons for different drive train types. A comparison between failure rates from this analysis and failure rates from similar analyses is also shown in this paper. View full abstract»

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  • A Wound Field Switched Flux Machine With Field and Armature Windings Separately Wound in Double Stators

    Page(s): 1 - 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2184 KB)  

    In this paper, a double stator (DS) wound field (WF) switched flux (SF) (DS-WFSF) machine is proposed. In the DS-WFSF machine, field and armature windings are separately placed in two different stators. Compared with the conventional WFSF machine with single stator, in which both field and armature windings are located, nonoverlapping concentrated windings and large slot areas can be obtained in the DS-WFSF machine. The proposed DS-WFSF machine exhibits >19% higher torque than the conventional WFSF machine, with both machines having the same space envelope and being globally optimized. The influence of leading design parameters, such as copper loss ratio between the field and armature windings, air-gap diameter, and rotor iron piece thickness and widths, on the average output torque is investigated for the DS-WFSF machines having 12/10, 12/11, 12/13, and 12/14 stator slots/rotor iron pieces. All the analyses are confirmed by both finite element and experimental results. View full abstract»

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  • A Constant-Parameter Voltage-Behind-Reactance Synchronous Machine Model Based on Shifted-Frequency Analysis

    Page(s): 1 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1440 KB)  

    Recently, the concepts of dynamic phasors and shifted-frequency analysis (SFA) have received renewed attention as a possible solution framework for the modeling of power system components and transients, as opposed to using instantaneous time-domain variables or conventional phasors. In this paper, a new voltage-behind-reactance (VBR) synchronous machine model based on SFA is presented. Using dynamic phasors, the proposed model permits the use of a much larger range of step sizes to efficiently simulate electromagnetic and electromechanical transients. Moreover, the proposed model has a constant-parameter (CP) stator interface, which is simple to implement and numerically more efficient compared with the prior state-of-the-art models with rotor-position-dependent stator inductance matrices. Rigorous transient case studies demonstrate that the new model requires significantly fewer time steps than the conventional time-domain models, and is more efficient than the previously established variable-parameter SFA model. View full abstract»

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  • A Compensated DFT-Based Phase-Angle Estimation for Fast Motor-Bus Transfer Applications

    Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1061 KB)  

    Motor-bus transfer systems are designed to maintain process continuity during the transfer of a motor bus from one power source to an alternate power source. A proper motor-bus transfer system must be designed in such a way that it can operate fast, and prevent damages to the motors and loads connected to the transferred bus. This paper investigates the application challenges associated with the design of a fast motor-bus transfer system. The paper also proposes a compensated discrete-Fourier-transform-based algorithm that enables a fast and reliable bus transfer for power generating plants and industrial facilities. The main advantage of the proposed algorithm is its simple implementation using the commercially available relay technologies. The effectiveness of the proposed algorithm is validated through comprehensive digital simulation of realistic motor-bus transfer systems in the PSCAD/EMTDC and MATLAB software environments. View full abstract»

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  • Novel Fault Ride-Through Scheme and Control Strategy for Doubly Fed Induction Generator-Based Wind Turbine

    Page(s): 1 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1540 KB)  

    This paper presents a novel modulated series dynamic braking resistor (MSDBR) control strategy for enhancing the fault ride-through (FRT) of doubly fed induction generator-based wind turbines. The proposed cost-effective protection scheme introduces a voltage booster that offers series voltage compensation capability and provides a means of power evacuation to mitigate the power imbalance during grid faults. To attain flexible and robust control solution for handling both balanced and unbalanced grid faults, the proposed scheme employs a modulated pulse width modulation (PWM) switching technique to control the stator phase voltage individually. The proposed transient management scheme allows the MSDBR to mitigate the impact from different types of grid faults and to fulfill with the recent grid code requirement. Also, reactive current injection capability during faults is also investigated with the proposed voltage reference algorithm. For the controller design, small-signal modeling is utilized with consideration of measurement dynamics for the tuning of controller parameters in order to ensure the system robustness and stability. Finally, the simulation results demonstrate the satisfactory performance of the MSDBR with its preferred allocation for enhancing the FRT performance against both balanced and unbalanced faults. View full abstract»

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  • Asynchronous Torque of Line-Starting Permanent-Magnet Synchronous Motors

    Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1410 KB)  

    A modified theory and a proposed analytical approach clarified asynchronous torque characteristics of line-starting permanent-magnet (PM) motors, taking into consideration the mutual effect among the fields due to armature current, cage-bar current, and PMs. Theoretical and analyzed results revealed that cage torque had an oscillating component with slip frequency due to magnetic saturation. This component cannot be seen in the conventional theory. It was also found that the coupling effect between PM flux and cage-bar flux caused on magnet torque larger oscillation and more significant negative dc component, compared with the case in the conventional theory. The theoretical and analyzed results were validated on the basis of experimental approaches. Results are given for a two-pole prototype motor with $P_{N} = 5$ kW, $n_{N} = 3000$ min−1, $V_{N} = 200$ V, and Y-connection. View full abstract»

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  • Implementation of a New MRAS Speed Sensorless Vector Control of Induction Machine

    Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1130 KB)  

    In this paper, a novel rotor speed estimation method using model reference adaptive system (MRAS) is proposed to improve the performance of a sensorless vector control in the very low and zero speed regions. In the classical MRAS method, the rotor flux of the adaptive model is compared with that of the reference model. The rotor speed is estimated from the fluxes difference of the two models using adequate adaptive mechanism. However, the performance of this technique at low speed remains uncertain and the MRAS loses its efficiency, but in the new MRAS method, two differences are used at the same time. The first is between rotor fluxes and the second between electromagnetic torques. The adaptive mechanism used in this new structure contains two parallel loops having Proportional-integral controller and low-pass filter. The first and the second loops are used to adjust the rotor flux and electromagnetic torque. To ensure good performance, a robust vector control using sliding mode control is proposed. The controllers are designed using the Lyapunov approach. Simulation and experimental results show the effectiveness of the proposed speed estimation method at low and zero speed regions, and good robustness with respect to parameter variations, measurement errors, and noise is obtained. View full abstract»

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  • Average-Value Modeling of Synchronous-Machine-Fed Thyristor-Controlled-Rectifier Systems

    Page(s): 1 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1351 KB)  

    Due to the repeated switching, the detailed switch-level models of electrical machines coupled with power-electronic converters are computationally expensive and hard to linearize for small-signal frequency-domain analysis. Average-value modeling (AVM) has become an effective tool for small-signal analysis of power electronic systems and time-domain transient studies where the details of switching are not important and can be neglected. Recently, a parametric AVM (PAVM) approach has been developed for machine/diode rectifier systems. This paper extends the parametric approach to the machine/thyristor-controlled-rectifier systems, where the thyristor firing may be referenced to either the line voltages or the rotor position. An analytical average model for this system is also developed based on the recently proposed constant-parameter voltage-behind-reactance synchronous machine model. The new PAVM is compared against the original switching system, as well as the analytical AVM. It is shown that the PAVM can accurately predict both small-signal characteristics and large-signal transients of the original switching system in light and heavy modes, which represents an advantage over the analytical models which are typically implicit. View full abstract»

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  • Influence of Rectifiers on High-Speed Permanent Magnet Generator Electromagnetic and Temperature Fields in Distributed Power Generation Systems

    Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (708 KB)  

    A power converter is very necessary in the system of high-speed permanent magnet generators (HSPMG), since the frequency of the output electrical energy is generally hundreds of Hertz or even more than 1000 Hz. However, the converter with switches in fast on–off transitions will have some effects on the generator and, therewith, some current harmonics will be also induced in the device. Taking a 117 kW 60 000 r/min HSPMG as an example, the harmonics in this generator were analyzed. And then, the voltage harmonic content, the current harmonic content, and the current total harmonic distortion could be obtained. In addition, stator core losses and rotor eddy current losses were analyzed comparatively, and the influence of the converter on the generator power factor was further studied. Based on the 3-D coupling field between fluid and temperature, the temperature distributions were obtained when the generator was connected to different loads, and the influence of the rectifier on the generator temperature field could be obtained, which was also compared with the test data. View full abstract»

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  • Influence of Voltage Balancing on the Temperature Distribution of a Li-Ion Battery Module

    Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (764 KB)  

    Temperature is one of the key factors when working with lithium-ion battery modules due to its influence in safety, performance, and lifespan concerns in these devices. High working temperatures reduce the available capacity of each cell within the module after several cycles due to aging; nonuniform temperature distributions in the module lead to different aging processes in each cell, and thus it will be impossible to take advantage of all the energy available in the Li-ion storage system, because the most aged cell will limit the available energy. This paper is focused on the minimization of the maximum temperature gradient of a battery module for high depth of discharge applications to avoid different aging processes of the cells within the module. Voltage balancing is proposed as a solution for this purpose, and different strategies and their results are presented in this paper. View full abstract»

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  • Leakage Field Analytical Computation in Semiclosed Slots of Unsaturated Electric Machines

    Page(s): 1 - 10
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (743 KB)  

    Slot leakage field accounts for an important quota of the total leakage flux in electric machines. The computation of unsaturated slot leakage inductances can rely on analytical formulas for simple open slot shapes, while the case of semiclosed slots is more critical and typically requires finite element analysis (FEA) or analytically solving the field over the whole machine domain. This paper sets forth an analytical procedure for computing the leakage field in semiclosed slots of unsaturated electric machines. The method is based on solving Maxwell's equations in the slot domain alone, which is made possible by appropriately defining boundary conditions in the slot opening region. The method proposed is assessed by comparison with FEA. Validations indicate that a good accuracy is achieved by the presented approach in predicting unsaturated leakage inductances, while FEA is required when magnetic saturation effects need to be taken into account. View full abstract»

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  • A Mitigation Strategy for Temporary Overvoltages Caused by Grid-Connected Photovoltaic Systems

    Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1144 KB)  

    Widespread penetration of distributed generators (DGs) into the power system has aggravated the problem of temporary overvoltages (TOVs), which can inflict substantial damages on the DGs, equipment, and other customers. Through slight modifications to the power-electronic circuit and its control, this paper proposes a strategy for limiting the TOVs caused by single-stage grid-connected photovoltaic (PV) energy systems. This paper also proposes a reduced TOV mitigation strategy for applications where a somewhat less effective, but also less expensive, solution is acceptable. The effectiveness of the proposed TOV mitigation strategy is demonstrated through time-domain simulation studies conducted on a detailed switched model of a study PV system in the PSCAD/EMTDC software environment. View full abstract»

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  • Analytical Algorithm for Strand End Leakage Reactance of Transposition Bar in AC Machine

    Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1328 KB)  

    Calculation of circulating current in transposition bars is the key problem in the design of stator windings, which will determine the transposition type of stator windings. The circuit equation method, in which the calculation of strand end leakage reactance in transposition bars is the premise, is widely used in engineering to calculate circulating current. This paper describes an analytical algorithm for the calculation of strand end leakage reactance in transposition bars, which is based on mirror image principle. The end leakage reactance of strands in transposition bar is calculated by the integral of transposition path discretized into many key points. Contrary to the existing calculation method, the analytical algorithm proposed in this paper is a general method for calculating the end leakage reactance, which can simulate the transposition path of strands in the end region for different transposition types. In order to validate the proposed method, the end coil self and mutual leakage reactance are calculated by proposed analytical algorithm and finite element method. View full abstract»

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  • Collaborative Control of DFIG System During Network Unbalance Using Reduced-Order Generalized Integrators

    Page(s): 1 - 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1376 KB)  

    The paper presents a collaborate control for the rotor-side converter (RSC) and grid-side converter (GSC) of a doubly fed induction generator (DFIG) generation system during network unbalance. In this study, the RSC is controlled to reduce the torque ripples, and three selectable control targets for the GSC, i.e., balanced total currents, and constant total active or reactive power into the grid from the overall system are identified to reduce the impacts of the negative-sequence voltage on the DFIG system performance. A reduced-order generalized integrator is employed, which is implemented in the positive synchronous reference frame. Based on the math model, the impacts of the limited dc voltage, as well as the rejection capability on negative-sequence voltage of the proposed control strategy, have been investigated. Finally, the simulation and experimental results are provided to demonstrate the effectiveness of the proposed collaborative control strategy. View full abstract»

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  • Squirrel-Cage Induction Motor Parameter Estimation Using a Variable Frequency Test

    Page(s): 1 - 8
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2370 KB)  

    This paper presents a method for squirrel-cage induction motor parameter estimation using a phase-to-phase standstill variable frequency test. The measured resistance and reactance at different frequencies are the data of the minimization error function to be minimized for single- and double-cage model parameters estimation. It is observed that the single-cage model is unable to fit the measured data for frequencies above several tenths of Hertz, whereas the double-cage model fits the measured data accurately in all the frequency ranges (from 0 to 150 Hz). The single- and double-cage estimated parameters are validated by comparison with data from two additional tests: 1) steady-state torque and current measurement test at different speeds; and 2) dynamic free-acceleration test. Again, the agreement between measured and predicted torque (in the first test) and current (in both tests) is satisfactory only for the double-cage model. View full abstract»

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  • A Distributed Magnetic Circuit Approach to Analysis of Multiphase Induction Machines With Nonsinusoidal Supply

    Page(s): 1 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (987 KB)  

    A 15-phase induction machine supplied by voltages with third-order harmonic injection has nonsinusoidal magnetomotive forces distribution. This paper introduces a distributed magnetic circuit approach to perform magnetic circuit calculations in order to determine the magnetizing inductance for both the fundamental and third-harmonic component. The proposed approach divides the half-pole or one-pole machine model into a large number of fan-shaped sectors. The air-gap flux densities for all sectors are then solved iteratively. The fundamental and third-harmonic inductances are extracted via Fourier analysis of air-gap flux density distribution. Calculated fundamental and third-order harmonic inductances are compared with those obtained from no-load tests of a 15-phase prototype induction machine. The good agreement between calculated and experimental results verifies the accuracy of the presented method. 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