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Cryogenic Testing Titles |
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Titles:
Elbuluk, M. E., Gerber, S. S., Hammoud, A., and Patterson, R., “Cryogenic Evaluation of an Advanced DC/DC Converter Module for Deep Space Applications,” IAS, 2002. DC/DC converters are widely used in power management, conditioning, and control of space power systems. Deep space applications require electronics that withstand cryogenic temperature and meet a stringent radiation tolerance. In this work, the performance of an advanced, radiation-hardened (rad-hard) commercial DC/DC converter module was investigated at cryogenic temperatures. The converter was investigated in terms of its steady state and dynamic operations. The output voltage regulation, efficiency, terminal current ripple characteristics, and output voltage response to load changes were determined in the temperature range of 20°C to -140°C. These parameters were obtained at various load levels and at different input voltages. The experimental procedures along with the results obtained on the investigated converter are presented and discussed.
Three magnetic powder cores and one ferrite core, which are
commonly used in inductor and transformer design for switch mode power
supplies,
were selected for investigation at cryogenic temperatures. The powder
cores
are Molypermalloy Core (MPC), High Flux Core (HFC), and Kool Mu Core
(KMC).
The performance of four inductors utilizing these cores has been
evaluated
as a function of temperature from 20°C to –180°C. All cores were wound
with the same wire type and gauge to obtain equal values of inductance
at
room temperature. Each inductor was evaluated in terms of its
inductance,
quality (Q) factor, resistance, and dynamic hysteresis characteristics
(B-H
loop) as a function of temperature and frequency. Both sinusoidal and
square
wave excitations were used in these investigations. Measured data
obtained
on the inductance showed that both the MPC and the HFC cores maintain a
constant inductance value, whereas with the KMC and ferrite core hold a
steady value in inductance with frequency but decrease as temperature
is decreased. All cores exhibited dependency, with varying degrees, in
their quality factor and resistance on test frequency and temperature.
Except for the ferrite, all cores exhibited good stability in the
investigated properties with temperature as well as frequency. Details
of the experimental procedures and test results are presented and
discussed in the paper. Deep space probes and planetary exploration missions require
electrical power management and control systems that are capable of
efficient and reliable operation in very cold temperature environments.
Typically, in deep space probes, heating elements are used to keep the
spacecraft electronics near room temperature. The utilization of power
electronics designed for and
operated at low temperature will contribute to increasing efficiency
and
improving reliability of space power systems. At NASA Glenn Research
Center,
commercial-off-the-shelf devices as well as developed components are
being
investigated for potential use at low temperatures. These devices
include
semiconductor switching devices, magnetics, and capacitors. Integrated
circuits
such as digital-to-analog and analog-to-digital converters, DC/DC
converters,
operational amplifiers, and oscillators are also being evaluated. In
this
paper, results will be presented for selected analog-to-digital
converters,
oscillators, DC/DC converters, and pulse width modulation (PWM)
controllers. NASA’s plans to explore remote bodies in the Solar System will subject spacecraft and surface craft to environmental temperature extremes. For example, calculations indicate about 120 K (–150°C) at the orbit of Jupiter and about 44 K (–230°C) at the orbit of Pluto. Even the moon, Mars, and asteroids can subject surface craft to temperatures well below the conventional limit for electronic parts of –55/–65°C. Incorporating thermal control into spacecraft and surface craft to maintain electronic systems within the conventional temperature range of –55°C to +125°C will become increasingly less desirable and less practical. Elimination of thermal control would provide important benefits including decreased mass, size, complexity and power requirements. This would also result in reduced development time-and-effort and launch costs, as well as extended mission operations for longer observation or exploration time. Thus there are strong reasons to allow the electronics and other systems to assume a temperature near that of the environment, in other words to operate “cold.” To address the need for “cold” electronics, we have been investigating and developing semiconductor devices (diodes and transistors) specifically for use in cryogenic power conversion and conditioning circuitry as well as for driver circuitry (for motors or actuators). Because of the particular requirements of the NASA applications, we are using germanium (Ge) in the development of these semiconductor devices. Our investigations confirm that Ge devices, including diodes, junction field-effect transistors, and bipolar transistors, can operate over the entire cryogenic temperature range of interest (down to about 20-30 K). We are also proposing to develop cryogenic devices based on the silicon-germanium (SiGe) semiconductor materials system because of its compatibility with existing Si device fabrication and its greater design flexibility afforded by band-gap engineering.
Power electronic circuits and systems designed for deep space
applications and outer planetary exploration are required to operate
reliably and efficiently under extreme temperature conditions. This
requirement is dictated by the fact that the operational environments
associated with some of the space missions would encompass temperatures
as low as –183°C. The development and utilization of electronics
capable of low temperature operation would not only fulfill the
advanced technology requirements, but also would contribute to
improving circuit performance, increasing system efficiency, and
reducing development and launch costs. These benefits are generally
achieved by the improved intrinsic properties of some of the electronic
materials at low temperature,
reduced device losses, and the elimination of heating elements used in
conventional
systems at low temperatures. Power electronic circuits are widely used
in
space power systems in the areas of power management, conditioning, and
control.
In this work, the performance of certain power electronic components
and
systems was investigated under low temperature. These include
inductors,
capacitors, pulse-width-modulation (PWM) controllers, and advanced
commercial
DC/DC converter modules. Different properties were determined as a
function
of temperature in the range of 20°C to - 140°C, at various current and
voltages
levels. The experimental procedures along with the experimental data
obtained
are presented and discussed in this paper. A NASA-wide team, funded under the NASA Electronic Parts and Packaging Program (NEPP), was formed to collaborate and to establish reliability of various electronic parts/packaging and assemblies for operation under extreme cold temperatures. One of the primary objectives of the NEPP is to expedite the infusion of cutting edge technologies into the present and future NASA missions. Commercial-off-the-shelf (COTS) emerging electronic parts/packages due to their lower weight, increased functionality, and lower cost are excellent candidates for space missions if they are characterized to show that they will meet the stringent reliability and quality requirements. Characterizations, especially for the extreme cold temperatures, are required since very limited data are available by manufacturers or users. For severe military environments, the temperature conditions to –65°C are the lowest temperature for which these parts/packages and assemblies are qualified. New data beyond this relatively benign cold temperature are required for numerous NASA missions. Several parts/packages, based on the project recommendation for their immediate and future needs, were selected for detailed characterization to cold temperature regimes down to liquid nitrogen (-196°C), covering both Mars cold temperature (-125°C) and asteroid (-180°C) lander environmental requirements. Numerous parts/packages and assemblies were characterized during extreme temperature environmental tests. Several electrical parameters were characterized at discrete temperatures to –185°C to determine if they remain within their specification ranges. Both packages and circuit boards were subjected to nondestructive testing including optical, X-ray, and acoustic microcopy to document their integrity prior to environment exposure. Package/board assemblies were also subjected to X-ray to characterize solder joint integrity including void levels. Both parts and assemblies were subjected to thermal cycling with a large temperature swing enveloping numerous NASA missions. Details of the performed tests and the results obtained are presented.
The operation of power electronic systems at cryogenic
temperatures is anticipated in many NASA space missions such as
planetary exploration
and deep space probes. In addition to surviving the space hostile
environment, electronics capable of low temperature operation would
contribute to improving circuit performance, increasing system
efficiency, and reducing development and launch costs. As part of the
NASA Glenn Low Temperature Electronics Program,
several commercial high-speed Pulse Width Modulation (PWM) chips have
been
characterized in terms of their performance as a function of
temperature in the range of 25 to -196°C (liquid nitrogen). These chips
ranged in their electrical characteristics, modes of control, packaging
options, and applications. The experiment procedures along with the
experimental data obtained on the investigated chips are presented and
discussed. Power converters capable of operation at cryogenic temperatures are anticipated to play an important role in the power system architecture of future NASA deep space missions. Design of such converters to survive cryogenic temperatures will improve the power system performance, and reduce development and launch costs. Aerospace power systems are mainly a DC distribution network. Therefore, DC/DC and DC/AC converters provide the outputs needed to different loads at various power levels. Recently, research efforts have been performed at the NASA Glenn Research Center (GRC) to design and evaluate DC/DC converters that are capable of operating at cryogenic temperatures. This paper presents a summary of the research performed to evaluate the low temperature performance of five DC/DC converters. Various parameters were investigated as a function of temperature in the range of 20°C to –196°C. Data pertaining to the output voltage regulation and efficiency of the converters is presented and discussed.
Electronic components and systems capable of operation at
cryogenic temperatures are anticipated in many future NASA space
missions such as
deep space probes and planetary surface exploration. For example, an
unheated
interplanetary probe launched to explore the rings of Saturn would
reach
an average temperature near Saturn of about -183°C. In addition to
surviving
the deep space harsh environment, electronics capable of low
temperature
operation would contribute to improving circuit performance, increasing
system
efficiency, and reducing payload development and launch costs.
Terrestrial
applications where components and systems must operate in low
temperature
environments include cryogenic instrumentations, superconducting
magnetic
energy storage, magnetic levitation transportation system, and arctic
exploration. An on-going R&D program at the NASA Glenn Research
Center focuses on the development of reliable electronic devices and
efficient power systems capable of surviving in low temperature
environments. An overview of the
program will be presented in the paper. A description of the low
temperature
test facilities along wit selected data obtained from in-house
component
testing will also be discussed. Ongoing research activities that are
being
performed in collaboration with various organizations will also be
presented. Power processing electronic systems, data acquiring probes, and signal conditioning circuits are required to operate reliably under harsh environments in many of NASA’s missions. The environment of the space mission as well as the operational requirements of some of the electronic systems, such as infrared-based satellite of telescopic observation stations where cryogenics are involved, dictate the utilization of electronics that can operate efficiently and reliably at low temperatures. In this work, radiation-hard CMOS 8-bit flash A/D converters were characterized in terms of voltage conversion and offset in the temperature range of +25 to –190°C. Static and dynamic supply currents, ladder resistance, and gain and offset errors were also obtained in the temperature range of +125 to –190°C. The effect of thermal cycling on these properties for a total of ten cycles between +80 and -150°C was also determined. The experimental procedure along with the data obtained are reported and discussed in the paper.
In this paper, two second-generation high power density DC/DC
converter modules have been evaluated at low operating temperatures.
The power rating of one converter (Module 1) was specified at 150 W
with an input voltage range of 36-75 V and output voltage of 12 V. The
other converter (Module 2)
was specified at 100 W with the same input voltage range and an output
voltage
of 3.3 V. The converter modules were evaluated in terms of their
performance
as a function of operating temperature in the range of 25°C to -140°C.
The
experimental procedures along with the experimental data obtained are
presented
and discussed in this paper. The operation of power electronic systems at cryogenic temperatures is anticipated in many NASA space missions such as planetary exploration and deep space probes. In addition to surviving the space hostile environments, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing development and launch costs. As part of the on-going Low Temperature Electronics Program at NASA Glenn Research Center (GRC), several commercial-off-the-shelf (COTS) DC/DC converters have been characterized in terms of their performance as a function of temperature in the range of 20°C to -180°C. These converters ranged in electrical power from 8 W to 13 W, input voltage from 9 V to 75 V and an output voltage of 3.3 V. The experimental set-up and procedures along with the results obtained on the converters’ steady-state and dynamic characteristics are presented and discussed.
DC/DC converters that are capable of operating at cryogenic temperatures are anticipated to play an important role in the power systems of future NASA deep space missions. Design of these converters to survive cryogenic temperatures will improve the power system performance, and reduce development and launch costs. At the NASA Glenn Research Center Low Temperature Electronics Laboratory, several commercial off-the-shelf DC/DC converter modules were evaluated for their low temperature performance. Various parameters were investigated as a function of temperature, in the range of 20°C to –180°C. Data pertaining to the efficiency and voltage regulation of the tested converters is presented and discussed.
Electronic systems that are capable of operating at cryogenic
temperatures will be needed for many future NASA space missions,
including deep space probes and spacecraft for planetary surface
exploration. In addition to being able to survive the harsh deep space
environment, low-temperature electronics would help improve circuit
performance, increase system efficiency, and
reduce payload development and launch costs. Terrestrial applications
where
components and systems must operate in low-temperature environments
include
cryogenic instrumentation, superconducting magnetic energy storage,
magnetic
levitation transportation, systems, and arctic exploration. An ongoing
research and development project for the design, fabrication, and
characterization
of low-temperature electronics and supporting technologies at NASA
Glenn
Research Center focuses on efficient power systems capable of surviving
in
and exploiting the advantages of low-temperature environments.
Supporting
technologies include dielectric and insulating materials, semiconductor
devices,
passive power components, optoelectronic devices, and packaging and
integration
of the developed components into prototype flight hardware. An overview
of the project is presented, including a description of the test
facilities,
a discussion of selected data from component testing and a presentation
of
ongoing research activities being performed in collaboration with
various
organizations. The operation of power electronic systems at cryogenic temperatures is anticipated in many NASA space missions such as planetary exploration and deep space probes. In addition to surviving the space hostile environments, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing development and launch costs. As part of the on-going Low Temperature Electronics Program at NASA Glenn Research Center (GRC), several commercial-off-the-shelf (COTS) DC/DC converters have been characterized in terms of their performance as a function of temperature in the range of 20°C to - 180°C. These converters ranged in electrical power from 8-W to 13 W, input voltage from 9 V to 75 V and an output voltage of 3.3 V. The experimental set-up and procedures along with the results obtained on the converters’ steady-state and dynamic characteristics are presented and discussed.
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