Power electronics technology has gained significant maturity after several decades of dynamic evolution of power semiconductor devices, converters, pulse width modulation (PWM) techniques, electrical machines, motor drives, advanced control, and simulation techniques. According to the estimate of the Electric Power Research Institute, roughly 70% of electrical energy in the USA now flows through power electronics, which will eventually grow to 100%. In the 21st century, we expect to see the tremendous impact of power electronics not only in global industrialization and general energy systems, but also in energy saving, renewable energy systems, and electric/hybrid vehicles. The resulting impact in mitigating climate change problems is expected to be enormous. This paper, in the beginning, will discuss the global energy scenario, climate change problems, and the methods of their mitigation. Then, it will discuss the impact of power electronics in energy saving, renewable energy systems, bulk energy storage, and electric/hybrid vehicles. Finally, it will review several example applications before coming to conclusion and future prognosis.

Global Energy Scenario and Impact of Power Electronics in 21st Century

The need for power semiconductor devices with high-voltage, high- frequency, and high-temperature operation capability is growing, especially for advanced power conversion and military applications, and hence the size and weight of the power electronic system are reduced. Development of 15-kV SiC IGBTs and their impact on utility applications is discussed.

Smart grid technologies

The higher voltage blocking capability and faster switching speed of silicon-carbide (SiC) mosfet s have the potential to replace Si insulated gate bipolar transistors (IGBTs) in medium-/low-voltage and high-power applications. In this paper, a state-of-the-art commercially available 325 A, 1700 V SiC mosfet module has been fully characterized under various load currents, bus voltages, and gate resistors to reveal their switching capability. Meanwhile, Si IGBT modules with similar power ratings are also tested under the same conditions. From the test results, several interesting points have been obtained: different to the Si IGBT module, the over-shoot current of the SiC mosfet module increases linearly with the increase of the load current and it has been explained by a model of the over-shoot current proposed in this paper; the induced negative gate voltage due to the complementary device turn- off (crosstalk effect) is more harmful to the SiC mosfet module than the induced positive gate voltage during turn- on when the gate off-voltage is –6 V; the maximum dv / dt and di / dt (electromagnetic interference) during switching transients of the SiC mosfet module are close to those of the Si IGBT module when the gate resistance is larger than 8 Ω but the switching loss of the SiC mosfet module is much smaller; the switching losses of the Si IGBT module are greater than those of the SiC mosfet module even when the gate resistance of the former is reduced to zero. An accurate power loss model, which is suitable for a three-phase two-level converter based on SiC mosfet modules considering the power loss of the parasitic capacitance, has been presented and verified in this paper. From the model, a 96.2% efficiency can be achieved at the switching frequency of 80 kHz and the power of 100 kW.

Performance Evaluation of High-Power SiC MOSFET Modules in Comparison to Si IGBT Modules

The current state of wide bandgap device technology is reviewed and its impact on power electronic system miniaturization for a wide variety of voltage levels is described. A synopsis of recent complementary technological developments in passives, integrated driver, and protection circuitry and electronic packaging are described, followed by an outline of the applications that stand to be impacted. A glimpse into the future based on the current technological trends is offered.

Wide Bandgap Technologies and Their Implications on Miniaturizing Power Electronic Systems

As an increasing attention towards sustainable development of energy and environment, the power electronics (PEs) are gaining more and more attraction on various energy systems. The insulated gate bipolar transistor (IGBT), as one of the PEs with numerous advantages and potentials for development of higher voltage and current ratings, has been used in a board range of applications. However, the continuing miniaturization and rapid increasing power ratings of IGBTs have remarkable high heat flux, which requires complex thermal management. In this paper, studies of the thermal management on IGBTs are generally reviewed including analyzing, comparing, and classifying the results originating from these researches. The thermal models to accurately calculate the dynamic heat dissipation are divided into analytical models, numerical models, and thermal network models, respectively. The thermal resistances of current IGBT modules are also studied. According to the current products on a number of IGBTs, we observe that the junction-to-case thermal resistance generally decreases inversely in terms of the total thermal power. In addition, the cooling solutions of IGBTs are reviewed and the performance of the various solutions are studied and compared. At last, we have proposed a quick and efficient evaluation judgment for the thermal management of the IGBTs depended on the requirements on the junction-to-case thermal resistance and equivalent heat transfer coefficient of the test samples.

Thermal Management on IGBT Power Electronic Devices and Modules

The emergence of High-Voltage, High-Frequency (HV-HF) Silicon-Carbide (SiC) power devices is expected to revolutionize commercial and military power distribution and conversion systems. The DARPA Wide Bandgap Semiconductor Technology (WBST) High Power Electronics (HPE) program is spearheading the development of HV-HF SiC power semiconductor technology. In this paper, some of the recent advances in development of HV-HF devices by the HPE program are presented and the circuit performance enabled by these devices is discussed.

Recent Advances in High-Voltage, High-Frequency Silicon-Carbide Power Devices

This paper presents for the first time a full three-dimensional (3-D), multilayer, and multichip thermal component model, based on finite differences, with asymmetrical power distributions for dynamic electrothermal simulation. Finite difference methods (FDMs) are used to solve the heat conduction equation in three dimensions. The thermal component model is parameterized in terms of structural and material properties so it can be readily used to develop a library of component models for any available power module. The FDM model is validated with a full analytical Fourier series-based model in two dimensions. Finally, the FDM thermal model is compared against measured data acquired from a newly developed high-speed transient coupling measurement technique. By using the device threshold voltage as a time-dependent temperature-sensitive parameter (TSP), the thermal transient of a single device, along with the thermal coupling effect among nearby devices sharing common direct bond copper (DBC) substrates, can be studied under a variety of pulsed power conditions.

3-D Thermal Component Model for Electrothermal Analysis of Multichip Power Modules With Experimental Validation

A high-current, high-voltage-isolated gate drive circuit developed for characterization of high-voltage, high- frequency 10 kV, 100 A SiC MOSFET/JBS half-bridge power modules is presented and described. Gate driver characterization and simulation demonstrate that the circuit satisfies the gate drive requirements for the SiC power modules in applications such as the DARPA WBST-HPE solid state power substation (SSPS). These requirements include 30 kV voltage-isolation for the high-side MOSFETs, very low capacitance between the ground and floating driver sides, and 20 kHz operation. Block diagram and detailed discussion of principles of operation of the gate drive circuit are given, together with measured and simulated waveforms of performance evaluation.

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High-Voltage Isolated Gate Drive Circuit for 10 kV, 100 A SiC MOSFET/JBS Power Modules

A new 60 A, 4.5 kV SiC JBS diode is presented, and its performance is compared to a Si PiN diode used as the antiparallel diode for 4.5 kV Si IGBTs. The I-V, C-V, reverse recovery, and reverse leakage characteristics of both diode types are measured. The devices are also characterized as the anti-parallel diode for a 4.5 kV Si IGBT using a recently developed high-voltage, double-pulse switching test system. The results indicate that SiC JBS diodes reduce IGBT turn-on switching loses by about a factor of three in practical applications. Furthermore, the peak IGBT current at turn-on is typically reduced by a factor of six, resulting in substantially lower IGBT stress. Circuit simulator models for the 4.5 kV SiC JBS and Si PiN diodes are also developed and compared with measurements.

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Comparison of 4.5 kV SiC JBS and Si PiN diodes for 4.5 kV Si IGBT anti-parallel diode applications

This paper presents the simulation of a 100 A, 10 kV silicon carbide (SiC) half-bridge power module operating at 20 kHz in a behavioral boost converter circuit. In the half-bridge power module, 10 kV SiC power MOSFETs are used as the upper and lower switches, where 10 kV SiC junction barrier Schottky (JBS) anti-parallel diodes along with 100 V silicon JBS series reverse-blocking diodes are used to protect the SiC MOSFETs from reverse conduction. The behavioral boost converter is designed to operate a single power switch and a single power diode for continuous 20 kHz hard switching conditions at 5 kV and 100 A. The test circuit contains the model for the 100 A, 10 kV SiC half-bridge power module where the upper MOSFET gate is turned off. The simulated waveforms demonstrate fast switch performance (<100 ns) with minimal turn-on current spikes resulting from charging the capacitances of the other MOSFET and JBS diodes in the module. The results also indicate that the combination of the 10 kV SiC JBS anti-parallel diode with the series low-voltage silicon JBS reverse-blocking diode is effective in protecting the SiC MOSFETs from reverse conduction.

https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=32831

Jose M. Ortiz-Rodriguez

Papers

Recent Advances in High-Voltage, High-Frequency Silicon-Carbide Power Devices

3-D Thermal Component Model for Electrothermal Analysis of Multichip Power Modules With Experimental Validation

High-Voltage Isolated Gate Drive Circuit for 10 kV, 100 A SiC MOSFET/JBS Power Modules

Comparison of 4.5 kV SiC JBS and Si PiN diodes for 4.5 kV Si IGBT anti-parallel diode applications

Circuit simulation model for a 100 A, 10 kV half-bridge SiC MOSFET/JBS power module