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Recent progress in the identification of switching power converters using an all-digital controller has granted network analyzer functionality to the control platform. In particular, the cross-correlation technique provides a nonparametric identification of a converter's small-signal control-to-output frequency response. The literature shows the viability of this technique as well as a few improvements to the basic technique. This online network analyzer functionality allows new flexibility in the areas of online monitoring and adaptive control. In this paper, several improvements to the cross-correlation method of system identification are proposed that aim to further improve the accuracy of the frequency response identification, particularly at high frequencies near the desired closed-loop bandwidth frequency. Additionally, an extension to the cross-correlation method is proposed that allows measurement of the control loop gain without ever opening the feedback loop. Thus, performance and stability margins may be evaluated while maintaining tight regulation of the output. Simulation and experimental results are shown to verify the proposed improvements and extension. Index Terms--Correlation, loop gain, online identification.

The requirements for driving gallium nitride (GaN) heterostructure field-effect transistors (HFETs) and the design of a resonant drive circuit for GaN power HFET switches are discussed in this paper. The use of wideband III-nitride (such as GaN) devices today is limited to telecom and low-power applications. The current lack of high-frequency high-power drivers prevents their application in power converters. The proposed circuit is based upon resonant switching transition techniques, by means of an LC tag, to recover part of the power back into the voltage source in order to reduce the power loss. This circuit also uses level shifters to generate the zero and negative gate-source voltages required to turn the GaN HFET on and off, and it is highly tolerant to input-signal timing variances. The circuit reduces the overall power consumed in the driver and thus reduces the power loss. This is particularly important for high-frequency driver operation to take full advantage, in terms of efficiency, of the superior switching speed of GaN devices. In this paper, the topology of the low-power-loss high-speed drive circuit is introduced. Some simulation results and preliminary experimental measurements are discussed. Index Terms--Gallium nitride (GaN) heterostructure field-effect transistors (HFETs), high speed, resonant drive circuit.

This paper presents the application of compact insulated gate bipolar transistor and p-i-n diode models, including features such as local lifetime control and field-stop technology, to the full electrothermal system simulation of a hybrid electric vehicle converter using a lookup table of device losses. The vehicle converter is simulated with an urban driving cycle (the Federal Urban Driving Schedule), which is used to generate transient device temperature profiles. A methodology is also described to explore the converter reliability using the temperature profile, with rainflow cycle counting techniques from material fatigue analysis. The effects of ambient temperature, driving style, and converter design on converter reliability are also investigated. Index Terms--Compact modeling, electrothermal simulation, mission profile, power semiconductor devices, rainflow cycle counting, reliability, thermal cycling.

Although insulated-gate bipolar-transistor (IGBT) turn-on losses can be comparable to turn-off losses, IGBT turn-on has not been as thoroughly studied in the literature. In the present work IGBT turn on under resistive and inductive load conditions is studied in detail through experiments, finite element simulations, and circuit simulations using physics-based semiconductor models. Under resistive load conditions, it is critical to accurately model the conductivity-modulation phenomenon. Under clamped inductive load conditions at turn-on there is strong interaction between the IGBT and the freewheeling diode undergoing reverse recovery. Physics-based IGBT and diode models are used that have been proved accurate in the simulation of IGBT turn-off. Index Terms--Compact semiconductor device models, insulated-gate bipolar-transistor (IGBT) turn-on, interaction, physics-based semiconductor modeling.

This paper presents the development and implementation of a physics-based diode model which can simulate aspects of high-voltage diodes such as snappy recovery during punch-through and the modified carrier density profile due to local lifetime control. It uses a Fourier series solution for the ambipolar diffusion equation in the lightly doped base region. The model is compared with finite-element device simulations. A parameter extraction procedure for the diode with lifetime control is proposed in Part II. Index Terms--Lifetime control, physics-based model, p-i-n diode model, power semiconductor modeling, variable lifetime.

In this paper, a parameter extraction procedure for high-voltage diodes with local lifetime control is proposed. It is designed for use with the physics-based diode model described in Part I, which is capable of simulating diodes with local lifetime control. The parameter extraction procedure described requires a forward characteristic and a reverse recovery measurement. The parameter extraction procedure is illustrated using finite-element simulations. The physics-based model using the parameters extracted is then compared with experimental results. Index Terms--Lifetime control, physics-based model, p-i-n diode model, power semiconductor modeling, variable lifetime.

Recently, a simulation method for power electronic devices has emerged, which has high accuracy and short run times based on a Fourier model of the device physics. This paper describes the use of the Fourier models for diodes and insulated gate bipolar transistors (IGBTs) and implementation in MATLAB and Simulink in a formal optimization strategy. In particular, this paper investigates coupled circuit, diode, and IGBT behavior. Conclusions are drawn concerning device loading and circuit design, particularly the role of stray inductance. Index Terms--Circuit modeling, diode, insulated gate bipolar transistor (IGBT), MATLAB, optimization, physics-based semiconductor device models, power semiconductor modeling, simulation, Simulink.

A practical and accurate parameter extraction method is presented for the Fourier-based-solution physics-based insulated gate bipolar transistor (IGBT) and power diode models. The goal is to obtain a model accurate enough to allow switching loss prediction under a variety of operating conditions. In the first step of the extraction procedure, only one simple clamped inductive load test is needed for the extraction of the six parameters required for the diode model and of the 12 and 15 parameters required for the nonpunch-through (NPT) and punch-through (PT) IGBT models, respectively. The second part of the extraction procedure is an automated formal optimization step that refines the parameter estimation. Validation with experimental results from various structures of IGBT demonstrates the accuracy of the proposed IGBT and diode models and the robustness of the parameter extraction method. Index Terms--Insulated gate bipolar transistor (IGBT) model, optimized parameter extraction, parameter extraction, power diode model, semiconductor modeling.

The switching characteristics (turn-on and turn-off) and forward conduction drop of trench-gate punch-through insulated gate bipolar transistors (IGBTs) are examined over a temperature range of from -50[degrees]C to 125[degrees]C. An analytical description of the forward conduction voltage drop is presented based on temperature dependencies of the appropriate physical parameters and mechanisms. A physics-based PSpice model, incorporating much of the device behavior, is also described. Results from the model are compared to experimental waveforms. Index Terms--Electrothermal semiconductor models, insulated gate bipolar transistor (IGBT), physics-based power semiconductor models, power semiconductor modeling, punch-through (PT) IGBT.

The theory of synergetic control was introduced in a power electronics context in a previous paper. In this paper, we review the theory, then focus on some practical aspects with reference to both simulations and actual hardware. In particular, we address management of the current limit condition and solve it with several different approaches. Adaptive and other control laws are also introduced to improve the control performance. The various controls are evaluated by applying the classical voltage reference step test and the step load test. Index Terms--Current limit, dynamic parameter adaptation, integral error term, nonlinear control, switching converter, synergetic control theory.

The problems faced in generating analytical models for the insulated gate bipolar transistor (IGBT) and power diode are devising correct equations and determining realistic boundary conditions, especially for two-dimensional (2-D) features, while ensuring convergence of the models. These issues are addressed in this paper in relation to the temperature dependent modeling of NPT IGBTs and diodes. Simulation and experimental results are presented and compared to validate the modeling approach. Index Terms--IGBT, physics-based semiconductor device models, power diode, quasi-2-D semiconductor device models.

The high-voltage field-stop (FS) insulated gate bipolar transistor (IGBT) is a promising power device for high-power applications thanks to the robust characteristics offered by the FS technology, which combines the inherent advantages offered by punch-through and nonpunch-through structures while overcoming the drawbacks of each structure. in this paper, an electrothermal physics-based model for the FS IGBT is developed. The model contains a detailed description of the FS layer and it is validated using experimental results for a commercial 1200-V/60-A FS IGBT over the entire temperature range specified in the data sheets. The validated model is then used to simulate a 6.5-kV FS IGBT. The simulation results are compared with experimental results published in the literature and good agreement is obtained. Index Terms--Field-stop insulated gate bipolar transistor (FS IGBT), high voltage IGBT, physics-based power semiconductor models, power semiconductors modeling.

An advantage for some wide bandgap materials, that is often overlooked, is that the thermal coefficient of expansion (CTE) is better matched to the ceramics in use for packaging technology. It is shown that the optimal choice for uni-polar devices is clearly GaN. It is further shown that the future optimal choice for bipolar devices is C (diamond) owing to the large bandgap, high thermal conductivity, and large electron and hole mobilities. A new expression relating the critical electric field for breakdown in abrupt junctions to the material bandgap energy is derived and is further used to derive new expressions for specific on-resistance in power semiconductor devices. These new expressions are compared to the previous literature and the efficacy of specific power devices, such as heterojunction MOSFETs, using GaN are discussed. Index Terms--Breakdown voltage, critical electric field, diamond, GaN, power electronics, SiC, specific on-resistance, wide bandgap.

The process for designing digital controls for power electronics is typically quite convoluted and affords many opportunities for errors to occur. We present here a new and Complete method for rapid prototyping of digital controls that allows rapid realization of new designs. The approach uses a collection of tools that include both software (the virtual test bed (VTB) and Matlab/Simulink) and hardware (dSpace DSP). An example application of the methodology completes the discussion. Index Terms--Digital controls, dSpace DSP, power electronics, rapid prototyping, virtual test bed.

Octavio Paz is one of the few writers in the world to receive truly international acclaim. The 1930s were a crucial phase in the history of Spain which initiated Paz to write political reviews. By the 1960s, Paz became interested in philosophy and structuralist principles. Most of the writings by Paz focus on socio-political situations in Mexico. Paz's development as a writer and the influence of his international travels on his writing are discussed.

Latin American studies exist in a conceptual framework that has been dictated by Western scholarship. As such, knowledge gleaned by Latin American scholars results in images of Latin America that are one step removed from reality, and often contradictory. The very notion of a 'Latin America' is a Western construct. This construct subordinates the Otherness of Latin America to institutional roles that allow the Self of the West to disregard the equality or superiority of Latin Americans.

Most electronic ballasts for fluorescent lamps provide a sinusoidal lamp current at the switching frequency. The high-frequency current flowing through the lamp can generate significant radiated noise, which is unacceptable in noise-sensitive applications, such as fluorescent lights in airplanes. Using shielded enclosures for the lamps may solve the problem, but it is expensive. A discontinuous conduction mode (DCM) electronic ballast topology is presented which drives the lamp with line frequency current, just like a magnetic ballast. However, compared to a magnetic ballast, its weight is substantially reduced due to operation at 40 kHz switching frequency. The topology also ensures unity power factor at the input and stable lamp operation at the output. Index Terms--Electromagnetic interference, electronic ballasts, power factor correction.