SEARCH · Engineering Papers

Results for “CONNECTORS”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 433 records · Page 24

All sources NASA NTRS DOE OSTI

DOE OSTI2024

Creating a Universal PV Plug and Socket Standard

Photovoltaic connectors are designed to be quick and easy to install. Current connector qualification standards, such as UL 6703 and IEC 62852, are only intended to evaluate connectors from the same manufacturer and were recently changed to explicitly proscribe the mating of connectors from different manufacturers. Unfortunately, the industry has chosen to design connectors that will commonly connect together with those from other manufacturers. This is done to simplify installation avoiding the situations such as when the connectors on a microinverter, or other module level power electronics, do not match the connectors on the modules in the system. This rampant violation of electrical codes worldwide indicates that there is a strong desire and need to develop a universal connector standard. Here we present the initial approach and philosophy behind the formation of an IEC subgroup under TC82 WG2 looking at this problem. We intend to develop a standard where the materials and geometry of construction are specified to ensure compatibility and the design is intended to be of the highest quality. We expect that this connector will be more costly but especially in rooftop installations where power electronics requires matching components from several manufacturers, that this may still result in a net cost savings. These connectors must be of the highest quality because we wouldn’t want to develop a connector that precluded the manufacturing of a higher quality product, and because these will most commonly be used on rooftop installations where safety is more of a concern. Additionally, because we do not know which brands of connectors will be used together, we cannot simply rely on test results to ensure safety but must create a design that is as inherently safe as possible.

connectors↗

DOE OSTI2024

APT Flash Lamps for a New Laser at LLNL Memo

Each flashlamp is supported coaxially within a pyrex water-jacket tube by two identical connector assemblies, one at each end. These connector assemblies not only support the flashlamp mechanically, but also provide source and return pathways for flashlamp DI cooling water and for electrical current. At each end of the flashlamp, the (presumably) tungsten feed-through rod that supports the electrode is attached to a connector assembly through a Multilam fitting. O rings seated on the outside of each connector assembly form a water-tight seal between the connector assembly and the inside of the pyrex water-jacket tube. During operation, DI cooling water enters the tube located at the end of one of the connectors, flows over that connector’s Multilam fitting, flows through a ring of holes in the connector assembly and then flows into the 1-mm gap between the flashlamp and the pyrex water-jacket tube. After passing over the length of the flashlamp, the water flows through the connector assembly at the opposite end of the flashlamp and exits through that connector assembly’s end tube. Electrical pulses are delivered to the flashlamp through the tubes coming out of the connector assemblies.

42 ENGINEERING↗

NASA NTRS2006

Correction for Thermal EMFs in Thermocouple Feedthroughs

A straightforward measurement technique provides for correction of thermal-electromotive-force (thermal-EMF) errors introduced by temperature gradients along the pins of non-thermocouple-alloy hermetic feedthrough connectors for thermocouple extension wires that must pass through bulkheads. This technique is an alternative to the traditional technique in which the thermal-EMF errors are eliminated by use of custom-made multipin hermetic feedthrough connectors that contain pins made of the same alloys as those of the thermocouple extension wires. One disadvantage of the traditional technique is that it is expensive and time-consuming to fabricate multipin custom thermocouple connectors. In addition, the thermocouple-alloy pins in these connectors tend to corrode easily and/or tend to be less rugged compared to the non-thermocouple-alloy pins of ordinary connectors. As the number of thermocouples (and thus pins) is increased in a given setup, the magnitude of these disadvantages increases accordingly. The present technique is implemented by means of a little additional hardware and software, the cost of which is more than offset by the savings incurred through the use of ordinary instead of thermocouple connectors. The figure schematically depicts a typical measurement setup to which the technique is applied. The additional hardware includes an isothermal block (made of copper) instrumented with a reference thermocouple and a compensation thermocouple. The reference thermocouple is connected to an external data-acquisition system (DAS) through a two-pin thermocouple-alloy hermetic feedthrough connector, but this is the only such connector in the apparatus. The compensation thermocouple is connected to the DAS through two pins of the same ordinary multipin connector that connects the measurement thermocouples to the DAS.

Ziemke, Robert A.↗

DOE OSTI2015

Electrical interconnect

An interconnect includes a first set of connector pads, a second set of connector pads, and a continuous central portion. A first plurality of legs extends at a first angle from the continuous central portion. Each leg of the first plurality of legs is connected to a connector pad of a first set of connector pads. A second plurality of legs extends at a second angle from the continuous central portion. Each leg of the second plurality of legs is connected to a connector pad of the second set of connector pads. Gaps are defined between legs. The gaps enable movement of the first set of connector pads relative to the second set of connector pads.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2020

System and method for a conformable pressure vessel

A vessel for storing fluid, the vessel including a liner having a liner body that defines: a liner cavity; a plurality of flexible connector portions that include a corrugated length that provides for flexibility of the respective connector portions, the connector portions having a first maximum diameter; a plurality of elongated tubing portions between the respective flexible connector portions, the elongated tubing portions having a second minimum diameter that is larger than the first maximum diameter of the flexible connector portions; and a plurality of taper portions coupling adjoining flexible connector portions and tubing portions configured to provide a transition between a smaller diameter of the connector portion and a larger diameter of the tubing portion.

33 ADVANCED PROPULSION SYSTEMS↗

NASA NTRS1996

Umbilical mechanism assembly for the international space station

Mechanisms for engaging and disengaging electrical and fluid line connectors are required to be operated repeatedly in hazardous or remote locations on space station, nuclear reactors, toxic chemical and undersea environments. Such mechanisms may require shields to protect the mating faces of the connectors when connectors are not engaged and move these shields out of the way during connector engagement. It is desirable to provide a force-transmitting structure to react the force required to engage or disengage the connectors. It is also desirable that the mechanism for moving the connectors and shields is reliable, simple, and the structure as lightweight as possible. With these basic requirements, an Umbilical Mechanism Assembly (UMA) was originally designed for the Space Station Freedom and now being utilized for the International Space Station.

Mandvi, A. Ali↗

NASA NTRS2001

Adhesive Bubble Removal Method and Apparatus for Fiber Optic Applications

An assembly for supporting a fiber optic termination or connector in a centrifuge and comprising a cylindrical body member having a top portion adapted to receive the ferrule body portion of a fiber optic termination or connector and a bottom portion for receiving a cylindrical piston/sealing unit is presented. The piston portion of the piston/sealing unit includes a compressible tip which is adapted to a butt up against the outer end of the ferrule body portion of the fiber optic termination or connector. A cylindrical end cap fits over the upper end of the body member for holding the fiber optic termination in place on the body member and causing a seal to be formed between the termination or connector and the upper portion of the body member adjacent the compressible tip of the plunger. The parts, when fitted together, are placed in a centrifuge which is operated for a predetermined spin cycle, so as to cause any bubbles in the uncured liquid adhesive to be vented outwardly from the termination through the end cap. Subsequent removal of the fiber optic termination or connector from the centrifuge and assembly is "bubble free" and ready to be joined with an optical fiber which is inserted in the ferrule end of the termination or connector.

John R Kolasinski↗

NASA NTRS1995

Umbilical mechanism

Apparatus is described for automatically mating a pair of connectors and protecting them prior to mating, which minimizes weight and uses relatively simple and reliable mechanisms. Lower and upper connectors (24, 26) are held in lower and upper parts (14, 16) of a housing, with the upper connector mounted on a carrier (32) that is motor driven to move down and mate the connectors. A pair of movable members (36, 38) serve as shields, as coarse alignment aids, and as force transmitters. The movable members are pivotally mounted at the bottom of the upper housing, and as the carrier moves down it pivots the members out of the way. The movable members have socket elements (116) that closely receive pin elements (120) on the lower housing part, to coarsely align the connectors and to react mating and unmating forces between the housings. The carrier has a pair of plate portions (60, 62) with slots (64), and the movable members have cam followers engaged with the slot walls, to move the members with precision. The carrier plate-like portions engage follower members (82) that pivot open lower shield parts (44, 46) covering the lower connector, which is mounted on four stacks of Belleville washers (142).

Barron, Daniel R.↗

NASA NTRS2005

Adhesive bubble removal method and apparatus for fiber applications

An assembly for supporting a fiber optic termination or connector in a centrifuge and comprising a cylindrical body member having a top portion adapted to receive the ferrule body portion of a fiber optic termination or connector and a bottom portion for receiving a cylindrical piston/sealing unit. The piston portion of the piston/sealing unit includes a compressible tip which is adapted to a butt up against the outer end of the ferrule body portion of the fiber optic termination or connector. A cylindrical end cap fits over the upper end of the body member for holding the fiber optic termination in place on the body member and causing a seal to be formed between the termination or connector and the upper portion of the body member adjacent the compressible tip of the plunger. The parts, when fitted together, are placed in a centrifuge which is operated for a predetermined spin cycle, so as to cause any bubbles in the uncured liquid adhesive to be vented outwardly from the termination through the end cap. Subsequent removal of the fiber optic termination or connector from the centrifuge and assembly is bubble free and ready to be joined with an optical fiber which is inserted in the ferrule end of the termination or connector.

Kolasinski, John R.↗

NASA NTRS2012

Dust-Tolerant Intelligent Electrical Connection System

Faults in wiring systems are a serious concern for the aerospace and aeronautic (commercial, military, and civilian) industries. Circuit failures and vehicle accidents have occurred and have been attributed to faulty wiring created by open and/or short circuits. Often, such circuit failures occur due to vibration during vehicle launch or operation. Therefore, developing non-intrusive fault-tolerant techniques is necessary to detect circuit faults and automatically route signals through alternate recovery paths while the vehicle or lunar surface systems equipment is in operation. Electrical connector concepts combining dust mitigation strategies and cable diagnostic technologies have significant application for lunar and Martian surface systems, as well as for dusty terrestrial applications. The dust-tolerant intelligent electrical connection system has several novel concepts and unique features. It combines intelligent cable diagnostics (health monitoring) and automatic circuit routing capabilities into a dust-tolerant electrical umbilical. It retrofits a clamshell protective dust cover to an existing connector for reduced gravity operation, and features a universal connector housing with three styles of dust protection: inverted cap, rotating cap, and clamshell. It uses a self-healing membrane as a dust barrier for electrical connectors where required, while also combining lotus leaf technology for applications where a dust-resistant coating providing low surface tension is needed to mitigate Van der Waals forces, thereby disallowing dust particle adhesion to connector surfaces. It also permits using a ruggedized iris mechanism with an embedded electrodynamic dust shield as a dust barrier for electrical connectors where required.

Lewis, Mark↗

NASA NTRS2019

Mechanical Design and Configuration of Penetrations for the Europa Clipper Avionics Vault Structure

The main purpose of the Avionics Vault is to shield radiation sensitive electronics for the Europa Clipper Spacecraft. The vault is a box structure made out of aluminum panels. The panels are roughly 10 mm thick in order to shield the electronics from the orbital total ionizing radiation around Jupiter. The vault requires an electromagnetic interference (EMI) shielding effectiveness (SE) of at least 70 dB in order to mitigate EMI with the spacecraft radar receiver. Overall, the vault accommodates four main types of penetrations: receptacle connectors, pass-through cables, fluid lines, and vent holes. More than 150 cables penetrate the vault panels to connect to electronic boxes inside. Fluid pipes enter and exit the vault to transfer heat to the rest of the spacecraft. Vent holes provide a path for air to escape from the vault during launch. Several novel penetrations designs were created to meet EMI and radiation shielding requirements. Receptacle connectors interface to the vault panels using 1.3 mm thick Ta10W plates. Pass-through cables penetrate the vault using aluminum clamshells after being wrapped with Teflon cushion tape, Kapton tape, and copper tape. Vent hole penetrations consist of a copper mesh for EMI shielding and an aluminum radiation shield bracket to direct air out of the vault during launch. Fluid lines terminate at the vault wall using mechanical fittings that resemble a nut and bolt interface. In addition, most mechanical seams and penetrations utilize EMI gaskets to ensure proper EMI shielding. To reduce risk and confirm that the vault penetration designs were appropriate for EMI shielding, an EMI chamber at the Jet Propulsion Laboratory (JPL) was used to test a mock-up vault panel with multiple variations of all four main types of vault penetrations. This EMI SE test also incorporated different methods for bundling pass-through cables, and a comparison of flange mounted connectors versus jam nut connectors. A low noise preamplifier and a Rohde & Schwarz spectrum analyzer measured E-field levels transmitting through the mock-up vault panel. The results showed a shielding effectiveness of 77 dB for the mock-up vault panel, which exceeds the 70 dB target for Europa Clipper. Both the flange mounted connectors and jam nut connectors exhibited similar EMI SE results at the measured frequencies, and all variations of vault penetrations showed favorable EMI SE levels. Since the flight panels will be much larger and include many more penetrations, there will be testing of the flight vault to confirm its EMI SE is compliant with environmental requirements.

Giersch, Louis↗

DOE OSTI2020

Micro-inverter assembly for use in a photovoltaic system and method of making same

A micro-inverter assembly for use in a photovoltaic system includes a housing, a direct current (DC)-to-alternating current (AC) micro-inverter disposed within the housing, and a DC connector electrically coupled to the DC-to-AC micro-inverter. The DC connector is positioned within a recess formed in a bottom surface of the housing such that at least one electrical contact of the DC connector is accessible from outside the housing. According to alternative embodiments, the DC connector comprises a plug-and-play connector constructed for one of a rotational engagement and a translational engagement with a DC connector of a photovoltaic (PV) panel.

Cioffi, Philip Michael↗

DOE OSTI2024

Recommended Actions to Improve Adapter Safety

With the rapid advancement and acceleration in the electric vehicle (EV) industry within the United States, major automakers and EV charging companies are increasingly adopting the North American Charging Standard (NACS) connector style, now officially known as J3400. This shift is expected to enhance charging infrastructure, providing a better customer experience by making it easier for all EV drivers to access a wider network of direct-current (DC) fast chargers (DCFCs). However, the adoption of the J3400 standard presents challenges for many EVs already on the roads and some currently coming off production lines that are equipped with the Combined Charging System (CCS) connector, which this report will refer to as the North American standard, CCS1. These vehicles will need adapters to use new or existing J3400 infrastructure. During this transition, several issues have emerged. Firstly, there is a need to standardize the new connector type to ensure it is interoperable, safe, and reliable. Second, existing CCS EV drivers need a way to access the J3400 network, which will require electric vehicle supply equipment (EVSE) or sites with both connector types, driver-provided adapters to physically convert from CCS to J3400, or EVSE with retained adapters designed for use with the EVSE. Third, adapter standards will need to be written to specify how they will be designed and what evaluations will be needed to ensure safe and reliable performance. To address these challenges, adapters that support different types of charging connectors will be essential. These adapters will play a crucial role in supporting the transition and ensuring continued service for legacy EVs with CCS inlets as the J3400 standard becomes the predominant one in the United States. Consequently, the National Charging Experience (ChargeX) Consortium has investigated and performed a teardown analysis on the different adapter versions on the market. The aim is to create a failure mode and effects analysis (FMEA) on what are expected to be the most common adapter types used in this transition. In order to support this work, we executed an FMEA exercise with the main goal of identifying gaps in the existing adapters' performance and conformance to the most common safety requirements of high-power and high-voltage devices. This effort focused on adapters provided by the driver, as these may present the highest safety and reliability risks. The recommendations made here apply to both retained and driver-provided adapters.

25 ENERGY STORAGE↗

NASA NTRS1977

Analytical study of electrical disconnect system for use on manned and unmanned missions

The program to survey existing electrical connector availability, and establish an optimum connector design for maintainable spacecraft substation interfaces is reported. Functional and operational requirements are given along with the results of the documentation survey, which disclosed that the MSFC series connectors have the preferred features of current connector technology. Optimum design concepts for EVA tasks, modules serviced by manipulators, and for manipulators independent of other servicing units are presented. It is concluded that separate connector designs are required for spacecraft replaceable modules, and for crewman EVA.

Rosener, A. A.↗

NASA NTRS1990

System for connecting fluid couplings

A system for mating fluid transfer couplings is constructed having a male connector which is provided with a pair of opposed rollers mounted to an exterior region thereof. A male half of a fluid transfer coupling is rotatably supported in an opening in an end of the connector and is equipped with an outwardly extending forward portion. The forward portion locks into an engagement and locking region of a female half of the fluid transfer coupling, with female half being rotatably supported in a receptacle. The receptacle has an opening aligned with locking region, with this opening having a pair of concentric, annularly disposed ramps extending around an interior portion of opening. These ramps are inclined toward the interior of the receptacle and are provided with slots through which rollers of the connector pass. After the connector is inserted into the receptacle (engaging forward portion into engagement region), relative rotation between the connector and receptacle causes the rollers to traverse ramps until the rollers abut and are gripped by retainers. This axially forces the forward portion into locked, sealed engagement with the engagement region.

Cody, Joseph C.↗

NASA NTRS2007

SiC Multi-Chip Power Modules as Power-System Building Blocks

The term "SiC MCPMs" (wherein "MCPM" signifies "multi-chip power module") denotes electronic power-supply modules containing multiple silicon carbide power devices and silicon-on-insulator (SOI) control integrated-circuit chips. SiC MCPMs are being developed as building blocks of advanced expandable, reconfigurable, fault-tolerant power-supply systems. Exploiting the ability of SiC semiconductor devices to operate at temperatures, breakdown voltages, and current densities significantly greater than those of conventional Si devices, the designs of SiC MCPMs and of systems comprising multiple SiC MCPMs are expected to afford a greater degree of miniaturization through stacking of modules with reduced requirements for heat sinking. Moreover, the higher-temperature capabilities of SiC MCPMs could enable operation in environments hotter than Si-based power systems can withstand. The stacked SiC MCPMs in a given system can be electrically connected in series, parallel, or a series/parallel combination to increase the overall power-handling capability of the system. In addition to power connections, the modules have communication connections. The SOI controllers in the modules communicate with each other as nodes of a decentralized control network, in which no single controller exerts overall command of the system. Control functions effected via the network include synchronization of switching of power devices and rapid reconfiguration of power connections to enable the power system to continue to supply power to a load in the event of failure of one of the modules. In addition to serving as building blocks of reliable power-supply systems, SiC MCPMs could be augmented with external control circuitry to make them perform additional power-handling functions as needed for specific applications: typical functions could include regulating voltages, storing energy, and driving motors. Because identical SiC MCPM building blocks could be utilized in a variety of ways, the cost and difficulty of designing new, highly reliable power systems would be reduced considerably. Several prototype DC-to-DC power-converter modules containing SiC power-switching devices were designed and built to demonstrate the feasibility of the SiC MCPM concept. In anticipation of a future need for operation at high temperature, the circuitry in the modules includes high-temperature inductors and capacitors. These modules were designed to be stacked to construct a system of four modules electrically connected in series and/or parallel. The packaging of the modules is designed to satisfy requirements for series and parallel interconnection among modules, high power density, high thermal efficiency, small size, and light weight. Each module includes four output power connectors two for serial and two for parallel output power connections among the modules. Each module also includes two signal connectors, electrically isolated from the power connectors, that afford four zones for signal interconnections among the SOI controllers. Finally, each module includes two input power connectors, through which it receives power from an in-line power bus. This design feature is included in anticipation of a custom-designed power bus incorporating sockets compatible with snap-on type connectors to enable rapid replacement of failed modules.

Lostetter, Alexander↗

NASA NTRS2013

Development of the Orion Crew-Service Module Umbilical Retention and Release Mechanism

The Orion CSM umbilical retention and release mechanism supports and protects all of the cross-module commodities between the spacecrafts crew and service modules. These commodities include explosive transfer lines, wiring for power and data, and flexible hoses for ground purge and life support systems. The mechanism employs a single separation interface which is retained with pyrotechnically actuated separation bolts and supports roughly two dozen electrical and fluid connectors. When module separation is commanded, either for nominal on-orbit CONOPS or in the event of an abort, the mechanism must release the separation interface and sever all commodity connections within milliseconds of command receipt. There are a number of unique and novel aspects of the design solution developed by the Orion mechanisms team. The design is highly modular and can easily be adapted to other vehiclesmodules and alternate commodity sets. It will be flight tested during Orions Exploration Flight Test 1 (EFT-1) in 2014, and the Orion team anticipates reuse of the design for all future missions. The design packages fluid, electrical, and ordnance disconnects in a single separation interface. It supports abort separations even in cases where aerodynamic loading prevents the deployment of the umbilical arm. Unlike the Apollo CSM umbilical which was a destructive separation device, the Orion design is resettable and flight units can be tested for separation performance prior to flight.Initial development testing of the mechanisms separation interface resulted in binding failures due to connector misalignments. The separation interface was redesigned with a robust linear guide system, and the connector separation and boom deployment were separated into two discretely sequenced events. These changes addressed the root cause of the binding failure by providing better control of connector alignment. The new design was tuned and validated analytically via Monte Carlo simulation. The analytical validation was followed by a repeat of the initial test suite plus test cases at thermal extremes and test cases with imposed mechanical failures demonstrating fault tolerance. The mechanism was then exposed to the qualification vibration environment. Finally, separation testing was performed at full speed with live ordnance.All tests of the redesigned mechanism resulted in successful separation of the umbilical interface with adequate force margins and timing. The test data showed good agreement with the predictions of the Monte Carlo simulation. The simulation proved invaluable due to the number of variables affecting the separation and the uncertainty associated with each. The simulation allowed for rapid assessment of numerous trades and contingency scenarios, and can be easily reconfigured for varying commodity sets and connector layouts.

Separation↗

DOE OSTI2025

Thermal Evaluation of CCS and NACS Reference Devices and Adapters

It is important for manufacturers of electric vehicle charging connectors, inlets, and adapters to understand the thermal performance of their devices. Various standards, such as SAE J1772, SAE J3400, IEC 62196, UL 2251, and UL 2252, list temperature limits that charging hardware needs to meet. However, there are currently very limited standardized reference devices against which to measure connector performance, and those that do currently exist generally serve charging currents less than 500A. This can make determining whether a charging connector meets the appropriate temperature limits difficult. Additionally, as automakers and charging station suppliers transition from the SAE J1772 CCS charging standard to SAE J3400 NACS, a number of CCS-to-NACS and NACS-to-CCS adapters are entering the market. These devices are being produced both by well-known automakers/equipment OEMs and lesser-known third-party suppliers, across a wide range of price points and construction qualities. Though SAE J3400/1 and UL 2252 lay out standards for adapter construction, performance and overtemperature response, there is no guarantee that any particular adapter will follow these standards and react to overtemperature events appropriately. This work addresses these issues by developing and evaluating a set of CCS and NACS reference inlet devices to validate the performance of charging connectors in the 500-800A range. The work also evaluates the performance of multiple NACS-to-CCS and CCS-to-NACS charging adapters with respect to UL 2252 temperature limits and SAE J3400/1 overtemperature signaling criteria.

33 ADVANCED PROPULSION SYSTEMS↗