Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Control System”

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.

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

At least 271 records · Page 15
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Micro-Environmental Control System (Final Report)

This project developed an innovative micro-environmental control system (µX) that enables office buildings to reduce energy used for heating and cooling by 15% or more. The µX is a compact, quiet, and ergonomic device that is designed to be installed under an office workstation; it is designed to maintain occupant comfort when room thermostat setpoints are incremented by 4°F or more (warmer in the summer and cooler in the winter) to save energy. When ambient room temperatures are outside of the usual comfort range, the µX maintains occupant comfort by delivering personalized cooling or heating locally to each office worker. The µX provides personalized cooling using a micro vapor compression system that includes a new high-performance micro-scroll compressor and a novel thermal storage unit. The vapor compression system operates at night to freeze a phase-change material (PCM). During the workday, the cooling stored in the PCM is released as a cool breeze of air to make occupants more comfortable. The micro-scroll compressor was developed specifically for this application; it is smaller than any of its type, minimizing the amount of power needed. In heating mode, the µX maintains occupant comfort using a foot heating mat with an infrared reflective box. The µX R&D project was conducted by Syracuse University in collaboration with United Technologies Research Center, Air Innovations, Bush Technical, and Cornell University. Over the course of the initial three-year project, the team developed and evaluated four versions of the unit, advancing the concept to Technology Readiness Level 6. The capabilities of individual proof-of-concept prototypes were verified in tests that were conducted with: 1) units in psychrometric chambers, 2) an instrumented manikin in a laboratory, and 3) human subjects in laboratories that simulate office environments. The tests verified that the µX prototypes met or exceeded all performance targets required to enable office buildings to reduce energy used for heating and cooling by 15% or more by maintaining occupant comfort when thermostat setpoints are incremented by 4°F or more.

25 ENERGY STORAGE↗
DOE OSTI2017

B827 Chemical Synthhesis Project - Industrial Control System Integration - Statement of Work & Specification with Attachments 1-14

The Chemical Synthesis Pilot Process at the Lawrence Livermore National Laboratory (LLNL) Site 300 827 Complex will be used to synthesize small quantities of material to support research and development. The project will modernize and increase current capabilities for chemical synthesis at LLNL. The primary objective of this project is the conversion of a non-automated hands-on process to a remoteoperation process, while providing enhanced batch process step control, stored recipe-specific parameter sets, process variable visibility, monitoring, alarm and warning handling, and comprehensive batch record data logging. This Statement of Work and Specification provides the industrial-grade process control requirements for the chemical synthesis batching control system, hereafter referred to as the “Control System” to be delivered by the System Integrator.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Hypergames and Cyber-Physical Security for Control Systems

The identification of the Stuxnet worm in 2010 provided a highly publicized example of a cyber attack that physically damaged an industrial control system. This raised public awareness about the possibility of similar attacks against other industrial targets—including critical infrastructure. Here, we use hypergames to analyze how strategic perturbations of sensor readings and calibrated parameters can be used to manipulate a system that employs optimal control. Hypergames form an extension of game theory that enables us to model strategic interactions where the players may have significantly different perceptions of the game(s) they are playing. Past work with hypergames has focused on relatively simple interactions consisting of a small set of discrete choices for each player. Here, we apply single-stage hypergames to larger systems with continuous variables. We find that manipulating constraints can be a more effective attacker strategy than manipulating objective function parameters. Moreover, the attacker need not change the underlying system to carry out a successful attack—it may be sufficient to deceive the defender controlling the system. It is possible to scale our approach up to even larger systems, but this will depend on the characteristics of the system in question, and we identify several characteristics that will make those systems amenable to hypergame analysis.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2018

Hydraulic Drive of a Shipping Lock Gate with Automated Frequency-Throttle Control System

This project developed and built a hydraulic actuator prototype with an automated control system for moving the lifting and lowering gates of a shipping lock. In the course of the design engineering, a hydraulic actuator was experimentally developed. Trial operation of a hydraulic actuator was conducted on Lock No. 26 of the Balakovo RGSiS. This design of a hydraulic actuator is recommended to be used in upgrading and designing locks of hydraulic engineering constructions.

42 ENGINEERING↗
DOE OSTI2021

Enhancements to the New TREAT Automatic Reactor Control System (ARCS)

The Transient Reactor Test (TREAT) facility recently replaced the automatic reactor control system (ARCS). Here, this paper discusses some of the enhancements that were made during the ARCS replacement such as calculations to take into account the nonadiabatic effects and increasing the dynamic range for power and period indication. This paper also discusses upgrades that had been planned but were unable to implemented and potential upgrades for the future.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2022

Anomaly Detection and Mitigation in FACTS-based Wide-Area Voltage Control Systems using Machine Learning

With the increasing deployment of Flexible AC Transmission System (FACTS) devices in wide-area voltage control systems (WAVCS) for achieving improved voltage stability of bulk power systems, the possibility for cyber attacks on these systems is also increasing. Successful stealthy cyber attacks that are difficult to detect by traditional informational technology (IT)-based cybersecurity solutions or threshold-based bad data detectors can lead to a voltage collapse in power grid. This paper presents the testbed-based attacks implementation and real-time evaluation of machine learning (ML) algorithm for detecting and mitigating stealthy cyber attacks on FACTS-based WAVCS on a hardware-in-the-loop (HIL) testbed. Initially, we discuss the implementation of a fuzzy logic controller (FLC) that controls a Static VAR Compensator (SVC) device deployed in a two-area four-machine Kundur power system for improving transient voltage stability. Later, the ML-based Anomaly Detection and Mitigation (ADM) system is implemented on the cyber-physical HIL testbed to detect and mitigate various stealthy cyber attacks, which are injected in real-time over the wide-area network (WAN). The experimental results show accurate and effective performance of ADM system in detecting and mitigating anomalies while keeping the grid stable and within the system operating limits, as defined by the North America Electric Reliability Corporation (NERC).

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2014

A modified Bitter-type electromagnet and control system for cold atom experiments

We present a modified Bitter-type electromagnet which features high magnetic field, fine electronic properties and efficient heat removal. The electromagnet is constructed from a stack of copper layers separated by mica layers that have the same shape. A distinctive design of cooling channels on the insulating layers and the parallel ducts between the layers ensures low resistance for cooling water to flow. A continuous current control system is also made to regulate the current through the electromagnet. In our experiment, versatile electromagnets are applied to generate magnetic field and gradient field. From our measurements, a peak magnetic field of 1000 G and a peak gradient field of 80 G/cm are generated in the center of the apparatuses which are 7 cm and 5 cm away from the edge of each electromagnet with a current of 230 A and 120 A, respectively. With the effective feedback design in the current control system and cooling water flow of 3.8 l/min, the stability of the current through the electromagnets can reach 10{sup −5}.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2023

Fault isolation and fault-tolerant control for nonlinear stochastic distribution control systems with multiplicative faults

Here, in this paper, a fault isolation, diagnosis and fault tolerant control algorithm is proposed for nonlinear multiple multiplicative faults stochastic distribution control systems employing Takagi–Sugeno fuzzy system. To obtain the detailed fault information, a fault detection algorithm is introduced to discover the fault occurrence time. Then a fault isolation observer is built to produce the residual, and the error system is separated to subsystems affected only by disturbance and multiplicative faults. Moreover, a fault estimation scheme is presented to obtain the fault magnitude information. When faults occur, the system output probability density function will deviate from the desired distribution. So the model predictive control fault tolerant control scheme is needed to minimize the impact of faults as much as possible to make sure that the post fault output probability density function track the desired probability density function. The validity of the designed algorithm is demonstrated through a simulation example, where the fault tolerant control algorithm ensures that the system output probability density function still track the given output probability density function despite the complex case of multiple multiplicative faults occurring simultaneously.

42 ENGINEERING↗
DOE OSTI2014

Analysis, testing, and operation of the MAGI thermal control system

The Aerospace Corporation has completed the development of the Mineral and Gas Identifier (MAGI) sensor - an airborne multi-spectral infrared instrument that is designed to discriminate surface composition and to detect gas emissions from the environment. Sensor performance was demonstrated in a series of flights aboard a Twin Otter aircraft in December 2011 as a stepping stone to a future satellite sensor design. To meet sensor performance requirements the thermal control system was designed to operate the HgCdTe focal plane array (FPA) at 50 K with a 1.79 W heat rejection load to a 44.7 K sink and the optical assembly at 100 K with a 7.5 W heat load to a 82.3 K sink. Two commercial off-theshelf (COTS) Sunpower Stirling cryocoolers were used to meet the instrument’s cooling requirements. A thermal model constructed in Thermal Desktop was used to run parametric studies that guided the mechanical design and sized the two cryocoolers. This paper discusses the development, validation, and operation of the MAGI thermal control system. Detailed energy balances and temperature predictions are presented for various test cases to demonstrate the utility and accuracy of the thermal model. Model inputs included measured values of heat lift as a function of input power and cold tip temperature for the two cryocoolers. These measurements were also used to make predictions of the cool-down behavior from ambient conditions. Advanced heater software was developed to meet unique requirements for both sensor cool-down rate and stability at the set point temperatures.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2014

Measurement and control system for cryogenic helium gas bearing turbo-expander experimental platform based on Siemens PLC S7-300

An experimental platform for cryogenic Helium gas bearing turbo-expanders is established at the Technical Institute of Physics and Chemistry, Chinese Academy of Sciences. This turbo-expander experimental platform is designed for performance testing and experimental research on Helium turbo-expanders with different sizes from the liquid hydrogen temperature to the room temperature region. A measurement and control system based on Siemens PLC S7-300 for this turbo-expander experimental platform is developed. Proper sensors are selected to measure such parameters as temperature, pressure, rotation speed and air flow rate. All the collected data to be processed are transformed and transmitted to S7-300 CPU. Siemens S7-300 series PLC CPU315-2PN/DP is as master station and two sets of ET200M DP remote expand I/O is as slave station. Profibus-DP field communication is established between master station and slave stations. The upper computer Human Machine Interface (HMI) is compiled using Siemens configuration software WinCC V6.2. The upper computer communicates with PLC by means of industrial Ethernet. Centralized monitoring and distributed control is achieved. Experimental results show that this measurement and control system has fulfilled the test requirement for the turbo-expander experimental platform.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2014

Single Stage Light Gas Gun Control System

The intermediate light gas gun at the STAR facility is used for shock wave physics testing with projectile speeds between 25 m/s and 1000 m/s. In order to operate the gun, there are several remote valves, pumps, and sensors that must be operated from the control room. In an effort to improve the engineered safety and efficiency of the gun's operation, a new gas plumbing and controls system must be implemented to simplify operator interaction with high pressure and lower the chance of human error. A new plumbing system has been designed which will allow the bottle farm system, where high pressure gas is stored, to be remotely operated during gun pressurization in addition to a new control system. This new system utilizes LabVIEW, which will communicate directly with a data acquisition and control device located in the gun bay to easily operate the gun pressurization and firing.

42 ENGINEERING↗
DOE OSTI2024

GQuEST Control System Resolution

GQuEST (Gravity from Quantum Entanglement of Space-Time), is a collaboration verifying a quantum gravity model by measuring holographic effects on a microscopic scale. Its interferometer apparatus filters excessive optical noise and requires a control system that can adjust the filtration to accommodate for frequency changes in the output light. We stress-test this control system by simulating filter behaviors with parameters in their outermost regimes, and we have determined a threshold that maintains precision while minimizing resource usage. These results are important for the successful operation of GQuEST's interferometer, enabling more accurate tests of quantum gravity models and thereby advancing our understanding of gravity at the quantum mechanical level.

Nguyen, David↗
DOE OSTI2019

Extending the Remote Control Capabilities in the CMS Detector Control System with Remote Procedure Call Services

The CMS Detector Control System (DCS) is implemented as a large distributed and redundant system, with applications interacting and sharing data in multiple ways. The CMS XML-RPC is a software toolkit implementing the standard Remote Procedure Call (RPC) protocol, using the Extensible Mark-up Language (XML) and a custom lightweight variant using the JavaScript Object Notation (JSON) to model, encode and expose resources through the Hypertext Transfer Protocol (HTTP). The CMS XML-RPC toolkit complies with the standard specification of the XML-RPC protocol that allows system developers to build collaborative software architectures with self-contained and reusable logic, and with encapsulation of well-defined processes. The implementation of this protocol introduces not only a powerful communication method to operate and exchange data with web-based applications, but also a new programming paradigm to design service-oriented software architectures within the CMS DCS domain. This paper presents details of the CMS XML-RPC implementation in WinCC Open Architecture (OA) Control Language using an object-oriented approach.

43 PARTICLE ACCELERATORS↗
DOE OSTI2012

INL Control System Situational Awareness Technology Annual Report 2012

The overall goal of this project is to develop an interoperable set of tools to provide a comprehensive, consistent implementation of cyber security and overall situational awareness of control and sensor network implementations. The operation and interoperability of these tools will fill voids in current technological offerings and address issues that remain an impediment to the security of control systems. This report provides an FY 2012 update on the Sophia, Mesh Mapper, Intelligent Cyber Sensor, and Data Fusion projects with respect to the year-two tasks and annual reporting requirements of the INL Control System Situational Awareness Technology report (July 2010).

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Software Dependability for Digital Instrumentation and Control Systems in Nuclear Power Plants - Lessons Learnt from a DOE Sponsored Project

This paper discusses the lessons learnt from a sponsored study undertaken under the sponsorship of the Department of Energy by a team of scientists at the Ohio State University in collaboration with Technology Resources and experts around the world. This paper makes recommendations for future research and studies based on these lessons learnt. The purpose of the research was to provide a software dependability quantification framework that would allow its evaluation along the software development life cycle for safety critical instrumentation and control systems (I and C) such as those found in nuclear power plants. A typical example of safety critical system is the reactor protection system. The research funded by the Department of Energy built on preliminary research carried out for the US NRC that had focused solely on software reliability quantification. Quantification of software dependability is important for safety critical I and C because the regulatory framework in use in the United States for nuclear power plants is risk informed. Quantification of risk requires quantification of all contributors to risk and those include instrumentation and control systems. The purpose of the study was to help developers of software-based I and C with an early evaluation of the potential risk an application would represent at different stages of the software development life cycle by building gates at the end of each life cycle phase. Life cycle phases of software development comprehend phases such as requirements, design, coding and test. The gates' function would be to stop development from moving forward if the assessed dependability objective for that phase were not met. Gates thresholds were to be defined based on measurements collected during the life cycle phase under evaluation and phases that preceded it and an understanding of the mechanisms that would lead to threatening the dependability objectives. The information contained in the gates would in addition help steer the development towards areas that needed improvement. The following are four high level conclusions to our study. First the study demonstrates a lack of consensus on mechanisms that will threaten the dependability attributes. This lack of consensus should be resolved. The lack of consensus appears for all measures to the exception of reliability. Second, measures should be developed for software availability and safety. Third, for all dependability attributes (with the exception of reliability) consistency of the measurement threads should evaluated and measurement-based development gates derived. Finally our ability to perform such type of research depends in a significant manner on access to vendor and/or utility data. The licensing environment and the first-of-a-kind nature of current software-based applications for nuclear I and C make it difficult to collect the relevant data. An approach which would either increase access to data by providing 'immunity' to the vendor or utility or the development of a software-based I and C for the sole purpose of data collection for research should be investigated. (authors)

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2021

Cryogenic control system operational experience at SNS

Abstract The helium cryogenic system at Spallation Neutron Source (SNS) provides cooling to 81 superconducting radio frequency cavities. To support the operation of the cryogenic facility, a highly reliable control system consisting of software, hardware, and Human Machine Interface (HMI) has been developed and improved during the first fifteen years of operation. Integrating the cryogenic control system with other subsystems of the SNS complex is an important aspect to the success of the operation. The operating experience, lessons learned and recommendations to consider for future facilities will be detailed in this paper.

Howell, M. (ORCID:0000000310360707)↗
DOE OSTI2011

Development of a new dynamic gas flow-control system in the pressure range of 1 Pa-133 Pa

A new flow-control system (FCS-705) has been developed at Korea Research Institute of Standards and Science. The system is intended for calibration of vacuum gauges in the pressure range of 1 Pa-133 Pa by comparison method. This paper describes some basic characteristics of the system including; (1) the design and construction of the system, (2) the generation of stable pressures in the chamber, (3) achieving high upstream pressure limit by installing a short duct in the by-pass pumping line, and (4) investigation of the gas flow regimes within the short duct.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2018

The DESI instrument control systems: status and early testing

The Dark Energy Spectroscopic Instrument (DESI) is a new instrument currently under construction for the Mayall 4-m telescope at Kitt Peak National Observatory. It will consist of a wide-field optical corrector with a 3.2 degree diameter field of view, a focal plane with 5,000 robotically controlled fiber positioners and 10 fiber-fed broad-band spectrographs. The DESI Instrument Control System (ICS) coordinates fiber positioner operations, interfaces to the Mayall telescope control system, monitors operating conditions, reads out the 30 spectrograph CCDs and provides observer support and data quality monitoring. In this paper, we summarize the ICS design, review the current status of the project and present results from a multi-stage test plan that was developed to ensure the system is fully operational by the time the instrument arrives at the observatory in 2019.

79 ASTRONOMY AND ASTROPHYSICS↗