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Brayton power system electrical subsystem and component performance tests, discussing engine control package, DC supply, inverters and instrumentation
Major power system technology development needs related to the solution of currently existing problems are defined. The identified problems were initially listed and categorized by technical area. They were then translated into terms of technology development requirements and consolidated where commonality was found. From these requirements, a set of ten specific recommendations for technology development was formulated.
Circuitry, power handling, and operational characteristics and anomalies of the Electrical Power System (EPS) of the Solar Maximum Mission are discussed. The EPS is designed as a standard unit to be a candidate for use on future space missions. Blown, improperly derated fuses in the Attitude Control System and the Signal Conditioning Assembly have led to switching to magnetrons for solar angle, with a loss of accuracy, and a loss of one-half of telemetry data, respectively. In addition, reasons for an 11-14% degradation of solar array output are uncertain due to the loss of precise attitude control. Current surges to peak at 76.5 A (down from 94.5 A) at sunrise, stays for four to five minutes, then resumes nominal output for the remainder of the 61-68 daytime period. Eclipse varies between 28 and 35 minutes, with corresponding depth of discharge of 14%. The batteries charge at 20 A, and although an overcharge mode has been continuously sensed, operation has been normal and temperature sensors have not indicated overcharge; cell failure has also not been sensed. The system has a two year design life and a desired life of four years.
Radioisotope Power Systems (RPS) are an invaluable resource for the exploration of our solar system. Providing both heat and electricity, spacecraft using RPS can operate where its impractical to use solar array and/or battery systems because of either limited solar illumination or mission durations which make a standalone battery impractical. This paper highlights the performance advantages which may come from using a RPS compared with a solar array/battery system. Included in this paper is an overview of the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), the Next-Generation RTG (NGRTG) and Dynamic Radioisotope System (DRPS). State-the-Art (SOA) performance of solar arrays and batteries is discussed. Finally, a comparison of both solar cell/battery systems compare with RPS are made at a variety of locations, both orbital and on the surface of some planets and their moons within our solar system.
Radioisotope Power Systems (RPS) are an invaluable resource for the exploration of our solar system. Providing both heat and electricity, spacecraft using RPS can operate where its impractical to use solar array and/or battery systems because of either limited solar illumination or mission durations which make a standalone battery impractical. This paper highlights the performance advantages which may come from using a RPS compared with a solar array/battery system. Included in this paper is an overview of the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), the Next-Generation RTG (NGRTG) and Dynamic Radioisotope System (DRPS). State-the-Art (SOA) performance of solar arrays and batteries is discussed. Finally, a comparison of both solar cell/battery systems compare with RPS are made at a variety of locations, both orbital and on the surface of some planets and their moons within our solar system.
Radioisotope Power Systems (RPS) are an invaluable resource for the exploration of our solar system. Providing both heat and electricity, spacecraft using RPS can operate where its impractical to use solar array and/or battery systems because of either limited solar illumination or mission durations which make a standalone battery impractical. This paper highlights the performance advantages which may come from using a RPS compared with a solar array/battery system. Included in this paper is an overview of the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG), the Next-Generation RTG (NGRTG) and Dynamic Radioisotope System (DRPS). State-the-Art (SOA) performance of solar arrays and batteries is discussed. Finally, a comparison of both solar cell/battery systems compare with RPS are made at a variety of locations, both orbital and on the surface of some planets and their moons within our solar system.
Modern power systems are evolving into sociotechnical systems with massive complexity, whose real-time operation and dispatch go beyond human capability. Thus, the need for developing and applying new intelligent power system dispatch tools are of great practical significance. In this paper, we introduce the overall business model of power system dispatch, the top level design approach of an intelligent dispatch system, and the parallel intelligent technology with its dispatch applications. We expect that a new dispatch paradigm, namely the parallel dispatch, can be established by incorporating various intelligent technologies, especially the parallel intelligent technology, to enable secure operation of complex power grids, extend system operators U+02BC capabilities, suggest optimal dispatch strategies, and to provide decision-making recommendations according to power system operational goals.
Requirements, design, and performance of control system from Brayton power system
Fission power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system.
This viewgraph presentation provides a detailed description of the Johnson Space Center's Power Systems Facility located in the Energy Systems Test Area (ESTA). Facilities and the resources used to support power and battery systems testing are also shown. The contents include: 1) Power Testing; 2) Power Test Equipment Capabilities Summary; 3) Source/Load; 4) Battery Facilities; 5) Battery Test Equipment Capabilities Summary; 6) Battery Testing; 7) Performance Test Equipment; 8) Battery Test Environments; 9) Battery Abuse Chambers; 10) Battery Abuse Capabilities; and 11) Battery Test Area Resources.
The Radioisotope Power Systems (RPS) program at Idaho National Laboratory (INL) fuels and performs environmental testing of RPS in support of National Aeronautics and Space Administration (NASA) missions. Recently the programs’ thermal vacuum chambers, housed within INL’s Space and Security Power Systems Facility (SSPSF), underwent successful renovations to improve functional capabilities and system control in support of customer missions. Thermal vacuum system renovations focused primarily on three core functions. The first focus area was integration of semi-automated Programmable Logic Controllers (PLC) to enhance operational feedback and process control. This included the use of numerically controlled vacuum valves and integration of real time feedback from process pressure transducers. Improvements to the system high vacuum pumping technology was the second priority focus. Legacy diffusion pumps were replaced with turbo-molecular and cryogenic pumps to help mitigate the possibility of back streaming diffusion pump oil onto the surface of the test article or radiative cooling surfaces located within the chambers. The third and final core function involved meeting emergent customer thermal requirements. This led to retro-fitting one of the vacuum chambers with a cryogenically cooled Thermal Conditioning Unit (TCU) and thermal shrouds. The TCU utilizes gaseous nitrogen to heat or cool a cylindrical shroud to maintain a set temperature with a programmable range of -I85 °C to I00 °C. With the successful completion of RPS acceptance testing, the newly renovated thermal vacuum chamber systems are operational and better equipped to support testing of Radioisotope Power Systems for space exploration missions.
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Future spacecraft power systems must be capable of supplying power to various loads. This delivery of power may necessitate the use of high-voltage, high-power dc distribution systems to transmit power from the source to the loads. Using state-of-the-art power conditioning electronics such as dc-dc converters, complex series and parallel configurations may be required at the interface between the source and the distribution system and between the loads and the distribution system. This research will use state-variables to model and simulate a dc spacecraft power system. Each component of the dc power system will be treated as a multiport network, and a state model will be written with the port voltages as the inputs. The state model of a component will be solved independently from the other components using its state transition matrix. A state-space averaging method is developed first in general for any dc-dc switching converter, and then demonstrated in detail for the particular case of the boost power stage. General equations for both steady-state (dc) and dynamic effects (ac) are obtained, from which important transfer functions are derived and applied to a special case of the boost power stage.
To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.
This paper presents a network hardware-in-the-loop (HIL) simulation system for modeling large-scale power systems. Researchers have developed many HIL test systems for power systems in recent years. Those test systems can model both microsecond-level dynamic responses of power electronic systems and millisecond-level transients of transmission and distribution grids. By integrating individual HIL test systems into a network of HIL test systems, we can create large-scale power grid digital twins with flexible structures at required modeling resolution that fits for a wide range of system operating conditions. This will not only significantly reduce the need for field tests when developing new technologies but also greatly shorten the model development cycle. In this paper, we present a networked OPAL-RT based HIL test system for developing transmission-distribution coordinative Volt-VAR regulation technologies as an example to illustrate system setups, communication requirements among different HIL test systems, and connection mechanisms. Impacts of communication delays, information exchange cycles, and computing delays are illustrated. Simulation results show that the performance of a networked HIL test system is satisfactory.
This is the final report of Phase 2 of the Secure Power Systems Professional project, a 3 phase project. DOE will post to their website upon release.
Abstract A power system is a complex cyber‐physical system whose security is critical to its function. A major challenge is to model, analyse and visualise the communication backbone of the power systems concerning cyber threats. To achieve this, the design and evaluation of a cyber‐physical power system (CPPS) testbed called Resilient Energy Systems Lab (RESLab) are presented to capture realistic cyber, physical, and protection system features. RESLab is architected to be a fundamental platform for studying and improving the resilience of complex CPPS to cyber threats. The cyber network is emulated using Common Open Research Emulator (CORE), which acts as a gateway for the physical and protection devices to communicate. The physical grid is simulated in the dynamic time frame using Power World Dynamic Studio (PWDS). The protection components are modelled with both PWDS and physical devices including the SEL Real‐Time Automation Controller (RTAC). Distributed Network Protocol 3 (DNP3) is used to monitor and control the grid. Then, the design is exemplified and the tools are validated. This work presents four case studies on cyberattack and defence using RESLab, where we demonstrate false data and command injection using Man‐in‐the‐Middle and Denial of Service attacks and validate them on a large‐scale synthetic electric grid.