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Results for “Gallium nitride (GaN) switches”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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Design of 1 kW Simplified Stirling Controller Using Capacitor-Based Power Factor Correction

Free-piston Stirling convertors hold potential for efficient, reliable thermal to electric power conversion, provided they are paired with a robust controller. This paper outlines work underway on a system-level optimization of a kW controller. Using simplified control and passive power factor correction (PFC) this design explores the possibility of reducing programmatic risk through system simplification. Efficiency is improved through incorporating wide-bandgap gallium nitride (GaN) switches, and PFC volume is minimized through the use of polymer multi-layer capacitors. This work is aimed at exploring new approaches for future Stirling space power concepts.

Stirling↗

Optimization, Design, and Demonstration of 1 kW Stirling Controller Using Capacitor-based Power Factor Correction

Free-piston Stirling convertors provide efficient, reliable thermal to electric power conversion, provided they are paired with a reliable controller. This paper outlines work underway on design concepts for kilowatt-class controllers. Using passive power factor correction (PFC) this design explores the possibility of reducing programmatic risk through system simplification. Efficiency is maximized through incorporating wide-bandgap gallium nitride (GaN) switches, and passive PFC volume is minimized through the use of polymer multi-layer capacitors. This work is aimed at exploring new approaches for future Stirling controllers.

Christopher Barth↗

Cryogenic Parametric Characterization of Gallium Nitride Switches

This report presents the parametric characterization results of four GaN field-effect transistor (FET) devices from three manufacturers, one of which is a cascode device, and compares those results to a Si power metal-oxide-semiconductor fieldeffect transistor (MOSFET) and a SiC power MOSFET. The devices were first characterized at ambient temperature, then at cryogenic temperatures down to -196 C (LN2 temperature), and finally at ambient temperature again in the event that the device parameters were permanently affected by the cryogenic temperatures. In general, the results indicate that the GaN devices show significant improvement overall at cryogenic temperatures in the parameters characterized, such as onresistance and leakage currents, compared to the Si and SiC devices. The results show that the SiC device tested should not be used at cryogenic temperatures due to the significant increase in on-resistance. The results also show that the GaN and Si parameters characterized were either not affected by the cryogenic temperatures or changed by no more than +/-20 percent post LN2 submersion. The device that exhibited the most parametric change post LN2 submersion was the SiC power MOSFET in its leakage currents.

Gonzalez, Marcelo C.↗

Demonstration of a Switched Wideband GaN High-Power Amplifier for Future Space Missions

In this paper, we present the architecture of a Ka-band switched, wideband, high efficiency gallium nitride based high-power amplifier. The architecture is validated by characterizing the driver and power amplifier chain. The measured results include Pout, Gain, PAE, RMS EVM for QPSK, Offset-QPSK, 8PSK, 16APSK, and 16QAM constellations, 3rd order IMD products, and noise figure. The wide bandwidth and high output power of the amplifier will enable future user terminals to interoperate between multiple service provider’s space networks.

high power amplifier↗

Demonstration of a Switched Wideband GaN High-Power Amplifier for Future Space Missions

In this paper, we present the architecture of a Ka-band switched, wideband, high efficiency gallium nitride based high-power amplifier. The architecture is validated by characterizing the driver and power amplifier chain. The measured results include Pout, Gain, PAE, RMS EVM for QPSK, Offset-QPSK, 8PSK, 16APSK, and 16QAM constellations, 3rd order IMD products, noise figure, and added phase noise. The wide bandwidth and high output power of the amplifier will enable future user terminals to interoperate between multiple service provider’s space networks.

Rainee N. Simons↗

Demonstration of a Switched Wideband GaN High-Power Amplifier for Future Space Missions

In this paper, we present the architecture of a Ka-band switched, wideband, high efficiency gallium nitride based high-power amplifier. The architecture is validated by characterizing the driver and power amplifier chain. The measured results include Pout, Gain, PAE, RMS EVM for QPSK, Offset-QPSK, 8PSK, 16APSK, and 16QAM constellations, 3rd order IMD products, noise figure, and added phase noise. The wide bandwidth and high output power of the amplifier will enable future user terminals to interoperate between multiple service provider’s space networks.

High power amplifier↗

Multi-Band and Multi-Function Reconfigurable Gallium Nitride Based Fully Solid-State Microwave Power Module for Cognitive Radio/Radar Platforms

This paper presents as a proof-of-concept (POC) the design, integration, and performance of a novel reconfigurable S-/X-band Gallium Nitride (GaN) based fully solid-state microwave power module (SSMPM) for the role as the transmit module in a cognitive radio (CR). The SSMPM synergistically integrates multiple amplifiers through diplexing and high power switches to enable a single SSMPM capable of functioning as both S-/X-band amplifiers for telemetry, tracking, and command (TT&C), telecommunications, and science data downlink or as X-band radar for proximity sensing onboard a planetary exploration spacecraft. Integration of an electric field shaping field plate (FP) onto the GaN high electron mobility transistors (HEMTs) in this SSMPM provides increased performance and reliability for operation in the harsh conditions of space. This SSMPM is capable of delivering saturated power (Psat) of 39 dBm (8 W continuous wave (CW)) at S-band, P(sub sat) of 43 dBm (20 W CW) at X-band, and P(sub sat) of >50 dBm (>100 W Pulsed) at X-band.

Simons, Rainee N.↗

Development of Gallium Nitride Monolithic Microwave Integrated Circuits for Ka-Band Remote Sensing

We have been developing gallium nitride (GaN)monolithic microwave integrated circuits (MMICs) towards thegoal of implementing a single chip transceiver frontend forcloud radar arrays at Ka-band. We present our first iterationdesign, fabrication and test cycle implementation of GaN poweramplifiers (PAs), low noise amplifiers (LNAs), driver amplifier,single-pole- double and triple throw switches, and voltagecontrolled attenuator. These components are necessary forimplementing a transceiver unit cell concept with digitalcalibration capabilities to enable scalable array sizes for radarand radiometry.

Cao, Yu↗

Characterization and Failure Analysis of 650 V Enhancement-Mode GaN HEMT for Cryogenically-Cooled Power Electronics

In order to evaluate the feasibility of newly developed GaN devices in a cryogenically-cooled converter, this paper characterizes a 650 V enhancement-mode Gallium-Nitride high-electron-mobility transistor (GaN HEMT) at cryogenic temperatures. The characterization includes both static and dynamic behaviors. The results show that this GaN HEMT is an excellent device candidate to be applied in cryogenic-cooled applications. For example, transconductance at cryogenic temperature (93 K) is 2.5 times higher than one at room temperature (298 K), and accordingly, peak di/dt during turn-on transients at cryogenic temperature is around 2 times of that at room temperature. Moreover, the on-resistance of the channel at cryogenic temperature is only one-fifth of that at room temperature. The corresponding explanations of performance trends at cryogenic temperatures are also given from the view of semiconductor physics. In addition, several device failures were observed during the dynamic characterization of GaN HEMTs at cryogenic temperatures. The ultra-fast switching speed induced high di/dt and dv/dt at cryogenic temperatures amplifies the negative effects of parasitics inside the switching loop. Based on failure waveforms, two failure modes were classified, and detailed failure mechanisms caused by ultra-fast switching speed are given in this paper.

Static and dynamic characterization↗

Amplifier Output Power, Gain, Efficiency, and Bandwidth: A Comparative Study of GaN HEMT MMIC Multi-Stage Power Amplifiers versus Distributed Power Amplifiers

In this paper we present first, the results of a study conducted to investigate the microwave performance of a wideband (25-31 GHz) GaN MMIC distributed high power amplifier (HPA). Second, we compare and contrast the above performance with that of an alternate architecture that relies on two HPAs to provide contiguous 25-31 GHz coverage. The two HPAs operate across 25-28 GHz and 27-31 GHz, respectively, and can be switched in and out depending on the need at any given time. The parameters investigated includes the output power, gain, power added efficiency, bandwidth, RMS error vector magnitude for offset-QPSK, 8PSK, 16APSK, and 32 APSK waveforms, 3rd-order intermodulation distortion products, noise figure, and single sideband phase noise.

MMIC↗