By Topic

Power Electronics, IEEE Transactions on

Issue 1 • Date Jan. 2007

Filter Results

Displaying Results 1 - 25 of 48
  • Table of contents

    Page(s): C1 - C4
    Save to Project icon | Request Permissions | PDF file iconPDF (46 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Power Electronics publication information

    Page(s): C2
    Save to Project icon | Request Permissions | PDF file iconPDF (39 KB)  
    Freely Available from IEEE
  • Editorial

    Page(s): 1 - 2
    Save to Project icon | Request Permissions | PDF file iconPDF (253 KB)  
    Freely Available from IEEE
  • Estimation and Measurement of Junction Temperatures in a Three-Level Voltage Source Converter

    Page(s): 3 - 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1215 KB) |  | HTML iconHTML  

    The design of a power converter must guarantee that the operating junction temperatures thetavj of all devices do not exceed their limits under all specified operating conditions. Usually, this is ensured by a simulative or analytical junction temperature estimation based on simple electrical and thermal models and semiconductor datasheet values. This paper discusses the difficulties and quantifies the limitations of this approach on the example of a three-level neutral point clamped voltage source converter (NPC VSC) with insulated gate bipolar transistors. The calculations are compared to the results of direct junction temperature measurements with an infrared camera. The paper also provides the experimental proof for the unequal loss and junction temperature distribution in the three-level NPC VSC View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Experimental Analysis of Punch-Through Conditions in Power P-I- N Diodes

    Page(s): 13 - 20
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1408 KB) |  | HTML iconHTML  

    Commercial power diodes are optimized to feature punch-through behavior. However, a tradeoff between the width and the doping level of the diode epitaxial layer leads to various levels of optimization. For a given breakdown voltage, a shorter epitaxial layer width leads to better transient performances. Device datasheets do not cover this issue and a simple experimental setup is presented to assess the optimization conditions inside the diode epitaxial layer. Three commercial devices are tested and experimental results are confronted to device simulations. A good agreement is found View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Equivalent Circuit Modeling of a Multilayer Planar Winding Array Structure for Use in a Universal Contactless Battery Charging Platform

    Page(s): 21 - 29
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1171 KB) |  | HTML iconHTML  

    In this paper, an equivalent circuit model of a multilayer planar winding array structure that can be used as a universal contactless battery charging platform is presented. This model includes the mutual-inductive effects of partial overlaps of planar windings in the multilayer structure. It has been successfully simulated with PSpice and practically verified with measurements obtained from three prototypes. This circuit model forms the basis of an overall system model of the planar charging platform. It is demonstrated that model parameters can be derived from the geometry of the winding structure. Errors between the calculated and the measured results are found to be within a tolerance of 5% View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Practical, Accurate and Very General Core Loss Model for Nonsinusoidal Waveforms

    Page(s): 30 - 40
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (944 KB) |  | HTML iconHTML  

    Nonsinusoidal voltage waveforms are quite common in high frequency power conversion magnetics. Low frequency nonsinusoidal waveforms are also common in ac motor applications with waveforms such as pulsewidth modulation and six-step. Previous attempts to model these losses, based on the Steinmetz equation, can work only in a limited range of frequencies, flux density excitations, and waveforms. In this paper, we present a very practical, yet very general and accurate model, for core loss calculations in case of nonsinusoidal voltage waveforms. We show the model is equally applicable to low and high frequencies, metallic as well as nonmetallic (e.g., ferrites) core materials, by comparing the model prediction with measured data for various waveforms, frequencies, and flux densities. The model can be used for the design of high frequency transformers and inductors for use in switched mode power supplies. The model can also be used for ac motors where it is hard to estimate "derating factor" and to avoid uncontrolled temperature rise View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Resistance Compression Networks for Radio-Frequency Power Conversion

    Page(s): 41 - 53
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1964 KB) |  | HTML iconHTML  

    A limitation of many high-frequency resonant inverter topologies is their high sensitivity to loading conditions. This paper introduces a new class of matching networks that greatly reduces the load sensitivity of resonant inverters and radio frequency (RF) power amplifiers. These networks, which we term resistance compression networks, serve to substantially decrease the variation in effective resistance seen by a tuned RF inverter as loading conditions change. We explore the operation, performance characteristics, and design of these networks, and present experimental results demonstrating their performance. Their combination with rectifiers to form RF-to-dc converters having narrow-range resistive input characteristics is also treated. The application of resistance compression in resonant power conversion is demonstrated in a dc-dc power converter operating at 100MHz View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Measurement-Based Method to Characterize Parasitic Parameters of the Integrated Power Electronics Modules

    Page(s): 54 - 62
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2918 KB) |  | HTML iconHTML  

    A measurement-based method for extracting the parasitic parameters of active power electronics modules (IPEMs) is proposed. Parasitic inductances and capacitances inside the IPEM can all be extracted using this method without destroying the structure. The linearized model is derived from impedance measurement and it is valid from low frequency to frequencies as high as 100 MHz. Extracted parameters are compared to those from commercial software and the results are in good agreement. A parallel resonance method is proposed for the characterization of common-mode capacitances View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Low Frequency Pulsed Resonant Converter for Energy Harvesting

    Page(s): 63 - 68
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (748 KB) |  | HTML iconHTML  

    A pulsed-resonant ac-dc converter and an integrated circuit (IC) controller have been designed, fabricated, and tested for harvesting energy from low-voltage (1.2V), low-power (1-100muW) energy transducers with output frequency in the 10-Hz-1-kHz range. Simulations using foundry models suggest that the silicon loss could be as low as 0.6muW, and the efficiency could reach 70%. With the IC experimentally packaged, the measured efficiency is between 50% and 70%, depending on the size and the loss in the resonant inductor View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Small Signal Analysis of Energy Factor and Mathematical Modeling for Power DC–DC Converters

    Page(s): 69 - 79
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (626 KB) |  | HTML iconHTML  

    Mathematical modeling for power dc-dc converters is a historical problem accompanying dc-dc conversion technology since the 1940s. The traditional mathematical modeling is not available for complex structure converters since the differential equation order increases very high. We have to search for other ways to establish mathematical modeling for power dc-dc converters. We have defined energy factor (EF) and new mathematical modeling for power dc-dc converters that have attracted much attention in recent years. This paper describes the small signal analysis of EF and mathematical modeling for power dc-dc converters in continuous conduction mode and discontinuous conduction mode. EF and the subsequential parameters can illustrate the unit-step response and interference recovery. This investigation may be helpful for system design and dc-dc converters characteristics. Two dc-dc converters: Buck converter and super-lift Luo-converter as the samples, are analyzed in this paper to demonstrate the applications of EF, pumping energy, stored energy (SE), capacitor/inductor SE ratio, energy losses, time constant tau, and damping time constant taud View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Soft Switching Circuit for Interleaved Boost Converters

    Page(s): 80 - 86
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (778 KB) |  | HTML iconHTML  

    A zero-voltage switching-zero-current switching interleaved boost converter is proposed in this paper. An active circuit branch in parallel with the main switches is added and it is composed of an auxiliary switch and a snubber capacitor. By using this interleaved converter topology, zero current turn-on and zero voltage turn-off of the main switches can be achieved and the reverse-recovery loss of boost diode can be reduced. In addition, the auxiliary switches are zero-voltage transmission during the whole switching transition. A prototype of boost converter rated at 1.2kW has been built to confirm the effectiveness of the converter View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Adaptive Neuro-Wavelet Control for Switching Power Supplies

    Page(s): 87 - 95
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (578 KB) |  | HTML iconHTML  

    The switching power supplies can convert one level of electrical voltage into another level by switching action. They are very popular because of their high efficiency and small size. This paper proposes an adaptive neuro-wavelet (ANW) control system for the switching power supplies. In the ANW control system, a neural controller is the main controller used to mimic an ideal controller and a compensated controller is designed to recover the residual of the approximation error. In this study, an online adaptive law with a variable optimal learning-rate is derived based on the Lyapunov stability theorem, so that not only the stability of the system can be guaranteed but also the convergence of controller parameters can be speeded up. Then, the proposed ANW control system is applied to control a forward switching power supply. Experimental results show that the proposed ANW controller can achieve favorable regulation performance for the switching power supply even under input voltage and load resistance variations View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Novel ZVS Resonant Reset Dual Switch Forward DC–DC Converter

    Page(s): 96 - 103
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (783 KB) |  | HTML iconHTML  

    This paper presents a new topology named zero-voltage switching (ZVS) resonant reset dual switch forward dc-dc converter, which, compared with resonant reset single switch forward dc-dc converter, maintains the advantage that duty cycle can be more than 50%, at the same time disadvantages of high voltage stress for main switches and low efficiency are overcome. In addition, ZVS is achieved for all switches of the presented topology. Therefore, this proposed topology is very attractive for high voltage input, wide range, and high efficiency applications. In this paper, the operation principle and characteristic of this topology are analyzed in detail. Next, the design consideration is presented. Finally, the advantages mentioned above are verified by experimental results View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Issues in the Delivery of RF Current Pulses to a Microprocessor

    Page(s): 104 - 112
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1400 KB) |  | HTML iconHTML  

    Passive and active filters are reviewed to define technology requirements for maintaining the impedance seen by the microprocessor below 1mOmega (100mV transient excursion on top of a 0.8-V, 120-A bus) in the gigahertz frequency range. The designs of these filters need to be coordinated so that the active filter does not have to carry the bulk of the real power or a significant amount of reactive power. Parasitic inductances need to be kept below a picohenry and amplifiers need to have bandwidth approaching a gigahertz to keep the loss below 10% of the real power View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Current Phase Lead Compensation in Single-Phase PFC Boost Converters With a Reduced Switching Frequency to Line Frequency Ratio

    Page(s): 113 - 119
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1755 KB) |  | HTML iconHTML  

    Traditional design of the current loop controller in a single-phase power factor correction boost converter is not suitable for applications with higher line frequencies (up to 800 Hz) because of the zero-crossing distortion and high harmonic content due to the current phase lead effect. Increasing the control bandwidth and switching frequency in order to avoid this effect would reduce converter efficiency and is objectionable. The paper presents the leading-phase admittance cancellation (LPAC) technique, which improves the current-shaping control structure and eliminates the current phase lead without increasing the bandwidth requirement. The LPAC method extends the allowable line frequency range from 1/150 to 1/5 of the current loop bandwidth. The LPAC method is load-invariant and superior to other previously proposed methods. The LPAC network can be added to existing designs, which would require only two passive components in the simplest case View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Analysis of the ZVS Two-Inductor Boost Converter under Variable Frequency Operation

    Page(s): 120 - 131
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2217 KB) |  | HTML iconHTML  

    The two-inductor boost converter has been previously presented in a zero-voltage switching (ZVS) form where the transformer leakage inductance and the MOSFET output capacitance can be utilized as part of the resonant elements. In many applications, such as maximum power point tracking (MPPT) in grid interactive photovoltaic systems, the resonant two-inductor boost converter is required to operate with variable input output voltage ratios. This paper studies the variable frequency operation of the ZVS two-inductor boost converter to secure an adjustable output voltage range while maintaining the resonant switching transitions. The design method of the resonant converter is thoroughly investigated and explicit control functions relating the circuit timing factors and the voltage gain for a 200-W converter are established. The converter has an input voltage of 20V and is able to produce a variable output voltage from 169V to 340V while retaining ZVS with a frequency variation of 1MHz to 407kHz. Five sets of theoretical, simulation and experimental waveforms are provided for the selected operating points over the variable load range at the end of the paper and they agree reasonably well. The converter has achieved part load efficiencies above 92% and an efficiency of 89.6% at the maximum power of 200W View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An Improvement Method of Matrix Converter Drives Under Input Voltage Disturbances

    Page(s): 132 - 138
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (767 KB) |  | HTML iconHTML  

    While the matrix converter has many advantages that include bidirectional power flow, a size reduction, a long lifetime, and sinusoidal input currents, it is vulnerable to the input voltage disturbances, because it directly exchanges the input voltage to the output voltage. The instantaneous effective power control (IEPC) method has been proposed to compensate the input voltage disturbances, in which the instantaneous effective power is kept constant by controlling input current. However, to date, no method has been proposed to maintain the stability of the system with the IEPC. The purpose of this paper is to propose a method to control the stability of the system with IEPC. First, this paper explains the IEPC theoretically. Next, a model of the system with the IEPC is developed, and stability analyses are conducted. Then, based on the results of the analyses, a stability control method for the system with the IEPC is proposed. Furthermore, the validities of the proposed method are demonstrated by simulation and experiments. Finally, a restart performance of the system after momentary power interruption is discussed. Because the IEPC does not need phase-locked-loop to detect the phase angle of the input voltage, fast restart is expected View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Comparison of Simple Control Strategies of Space-Vector Modulated Indirect Matrix Converter Under Distorted Supply Voltage

    Page(s): 139 - 148
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1490 KB) |  | HTML iconHTML  

    This paper concerns the effect of symmetric supply voltage harmonics in a space-vector modulated three-phase indirect matrix converter (IMC). The IMC is modulated using indirect space-vector modulation. The effect of symmetric supply harmonics on load voltages and currents is analyzed using space-vector presentation. The measurement and simulation results with distorted supply voltages are compared to the results with pure sinusoidal supply voltage. Four simple control methods of IMC are tested in simulations and measurements: 1) open-loop control without measurements (Method I); 2) calculation of modulation index using measured supply voltages (Method II); 3) closed-loop control of output currents (Method III); and 4) combination of Methods II and III, i.e., closed-loop output current control with supply voltage measurement (Method IV). All the methods are easy to implement and do not require complicated computing. It is noted that Methods II and IV, where modulation index is calculated using measured supply voltage magnitudes, can produce more sinusoidal load currents than Methods I and III, which suppose ideal supply conditions View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Novel Four-Level Voltage Source Inverter—Influence of Switching Strategies on the Distribution of Power Losses

    Page(s): 149 - 159
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1339 KB) |  | HTML iconHTML  

    In this paper, a novel four-level inverter will be presented and analyzed. The proposed inverter topology, which is composed of a conventional two-level and a three-level neutral-point clamped (NPC) inverter, is suitable for high-voltage and high-power applications. The proposed inverter, when it is compared with the conventional four-level NPC pulsewidth modulation inverter, exhibits the following advantages: a) ability of changing the power losses distribution profile among the devices by selecting a suitable switching strategy; b) reduction of total inverter power semiconductor device losses; c) ability of bidirectional operation for all power semiconductor switches; and d) easy implementation using existing power semiconductor modules. The effect of conduction and switching losses profiles of the proposed inverter for different switching strategies is examined under different loads, power factors, and modulation indices. The dc-link capacitors voltages are effectively balanced via a proposed self-voltage balancing topology, without the need of isolated dc voltage sources or additional voltage stabilizing circuits. Finally, the theoretical results are confirmed by simulation and experimental results View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Current Weighting Distribution Control Strategy for Multi-Inverter Systems to Achieve Current Sharing

    Page(s): 160 - 168
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1867 KB) |  | HTML iconHTML  

    A current-weighting-distribution-control (CWDC) strategy for multi-inverter systems to achieve current sharing is presented in this paper. With a CWDC strategy, the inverters connected in parallel are allowed to have different power ratings and can achieve a weighted output current distribution by adding only simple circuits to each inverter. In such systems, each inverter has an outer voltage loop controller to govern system stability, an inner current loop controller to expedite dynamic response, and a weighting current controller to achieve current distribution and to reduce possible interactive effects among inverters. Experimental results from a two-inverter system and a three-inverter system have demonstrated the feasibility of the proposed strategy in weighting current distribution and fast regulation during a step-load change or hot-swap operation View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Z-Source Current-Type Inverters: Digital Modulation and Logic Implementation

    Page(s): 169 - 177
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2059 KB) |  | HTML iconHTML  

    Traditionally, current source (CS) inverters have been adopted for use in medium and high power industry applications. These inverters, however, support only current-buck dc-ac power conversion and need a relatively complex modulator, as compared to conventional voltage source (VS) inverters. To address these limitations, this paper presents an integration of the buck-boost Z-source power conversion concept to the CS inverter topology to develop single- and three-phase Z-source CS inverters. For their efficient control, the paper starts by evaluating different carrier-based reference formulations to identify different inverter state placement possibilities. The paper then proceeds to design appropriate "reference-to-switch" assignments or logic equations for mapping out the correct CS gating signals, allowing a simple carrier-based modulator to control a Z-source CS inverter with complications such as commutation difficulties and "many-to-many" state assignments readily resolved. The developed system can be implemented using a digital signal processor with an embedded VS pulse-width modulator and an external programmable logic device, hence offering a competitive solution for medium power single and three-phase buck-boost power conversion. Theory, simulation, and experimental results are presented in the paper View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Modified Phase-Shifted PWM Control for Flying Capacitor Multilevel Converters

    Page(s): 178 - 185
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1307 KB) |  | HTML iconHTML  

    The issue of voltage imbalance remains a challenge for the flying capacitor multilevel converter. The phase-shifted pulsewidth modulation (PS-PWM) method has a certain degree of self-balancing properties. However, the method alone is not sufficient to maintain balanced capacitor voltages in practical applications. The paper proposes a closed-loop modified PS-PWM control method by incorporating a novel balancing algorithm. The algorithm takes advantage of switching redundancies to adjust the switching times of selected switching states and thus maintaining the capacitor voltages balanced without adversely affecting the system's performance. Key techniques of the proposed control method, including selection of switching states, calculation of adjusting times for the selected states, and determination of new switching instants of the modified PS-PWM are described and analyzed. Simulation and experimental results are presented to confirm the feasibility of the proposed method View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A Simple Analog Controller for Single-Phase Half-Bridge Rectifier

    Page(s): 186 - 198
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2480 KB) |  | HTML iconHTML  

    A simple analog controller is proposed for the single-phase half-bridge pulsewidth modulation rectifier to maintain near unity power factor at the input and balance the voltages across each half of the dc bus. The controller works in the principle of constant-frequency current programmed control. The required gating pulses are generated by comparing the input current with a linear and bipolar carrier without sensing the input voltage. Two voltage controllers and a single reset-integrator are used to generate the carrier. All the necessary control operations are performed without using any phase locked loop, multiplier, and/or divider circuits. Resistor based sensors are used to measure the voltages across two halves of the dc bus and the input current. The controller can be fabricated as a single integrated circuit. The averaged small signal models and all the necessary design equations are provided. The condition of stability against subharmonic oscillation is analyzed. Calculation of switching and conduction losses is presented. The control concept is validated through simulation and also experimentally on an 800-W half-bridge rectifier. Experimental results are presented for ac-dc application, and also for ac-dc-ac application with both linear and nonlinear loads at two different output fundamental frequencies (50 and 60Hz) View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Autotuning of Digitally Controlled DC–DC Converters Based on Relay Feedback

    Page(s): 199 - 207
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1448 KB) |  | HTML iconHTML  

    This paper proposes a simple autotuning technique for digitally controlled dc-dc converters. The proposed approach is based on the relay feedback method and introduces perturbations on the output voltage during converter soft-start. By using an iterative procedure, the tuning of proportional-integral-derivative parameters is obtained directly by including the controller in the relay feedback and by adjusting the controller parameters based on the specified phase margin and control loop bandwidth. A nice property of the proposed solution is that output voltage perturbations are introduced while maintaining the relay feedback control on the output voltage. The proposed algorithm is simple, requires small tuning times, and it is compliant with the cost/complexity constraints of integrated digital integrated circuits. Simulation and experimental results of a synchronous buck converter and of a dc-dc boost converter confirm the effectiveness of the proposed solution View full abstract»

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

Aims & Scope

IEEE Transactions on Power Electronics covers fundamental technologies used in the control and conversion of electric power.

Full Aims & Scope