Design of a prototype personal static var compensator

The focus of this thesis is the design and implementation of a personal static var compensator (PSVC) for distributed var control through load power factor correction. The PSVC demonstrates the two key benefits of power factor correction, which include decreased power costs and increased system capacity. The PSVC prototype consists of two types of branches---a TSC branch and a TCR branch. A microprocessor is responsible for calculating the load displacement power factor (PFD) and for executing the fuzzy logic control scheme for the two branches. The PSVC was found to reduce the RMS current drawn by a 55-watt AC motor by 25% while raising its PFD by 40% to 0.99 lagging. The expected quick rate of return of installation costs is attributed to the PSVC\u27s low initial cost and its ability to reduce tariffs for reactive power consumption

GTOSat: Radiation Belt Dynamics from the Inside

GTOSat, a 6U SmallSat integrated and tested at NASA Goddard Space Flight Center (GSFC), has a scheduled launch date of July 31st, 2022, on an Atlas V. From a low inclination geosynchronous transfer orbit (GTO), GTOSat has the primary science goal of advancing our quantitative understanding of acceleration and loss of relativistic electrons in the Earth’s outer radiation belt. It will measure energy spectra and pitch angles of both the seed and the energized electron populations simultaneously using a compact, high-heritage Relativistic Electron Magnetic Spectrometer (REMS) built by The Aerospace Corporation. A boom-mounted Fluxgate Magnetometer (FMAG), developed by NASA GSFC, will provide 3-axis knowledge of the ambient local magnetic field. The spacecraft bus uses a combination of commercial and in-house/custom designed components. Design, integration, and testing of the spacecraft bus was performed by a small, dedicated team at GSFC. Throughout development GTOSat has encountered numerous challenges, expected and unexpected, that we’re ready to share with the community

Development of Software-only Simulation Test Beds (SoST) for Spacecraft and SmallSats

Software-only-Simulation Test Beds (SoST) are beginning to become more popular among aircraft, spacecraft, and smallsat embedded system developers due to the high cost of duplicating hardware test beds. SoSTs provide a software-only, or virtual test bed, that creates a “digital twin” that contains software models of the ETUs and often includes modeled components such as flight computers, busses (e.g., MIL-STD-1553, SPI, I2C), compact PCI (cPCI) backplane cards, sensors, and actuators. The ultimate goal of a SoST is for it to run the native system software compiled-binary on its native CPU architecture (e.g., PowerPC, LEON3/4, ARM) on a standard X86 personal computer/laptop without needing to recompile for X86. This methodology maintains the “Test-As-You-Fly” approach and is a powerful capability when used in tandem with hardware ETU test beds. SoST integration into large projects is beginning to increase, with benefits being immediately realized. When implemented correctly, both technically and managerially, SoSTs can help solve the hardware “scarce resource” problem by providing a nearly unlimited test resource that can be utilized for earlier software unit testing, integration testing, and operator training, which results in schedule relief and improved quality and mission assurance. This dissertation focuses on developing the first SoST process guide using several past spacecraft missions and smallsat missions as examples. Also, West Virginia’s first spacecraft, Simulation-To-Flight-1 (STF-1), and its accompanying SoST, among other missions, will be utilized as case-studies and will cover the modeling of flight computers, avionics, dynamic simulators, and ground system components