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Lollar, L. F.

Publications and source records attributed to Lollar, L. F..

Knowledge-based systems for power management

NASA-Marshall's Electrical Power Branch has undertaken the development of expert systems in support of further advancements in electrical power system automation. Attention is given to the features (1) of the Fault Recovery and Management Expert System, (2) a resource scheduler or Master of Automated Expert Scheduling Through Resource Orchestration, and (3) an adaptive load-priority manager, or Load Priority List Management System. The characteristics of an advisory battery manager for the Hubble Space Telescope, designated the 'nickel-hydrogen expert system', are also noted.

Lollar, L. F.

Automating a spacecraft electrical power system using expert systems

Since Skylab, Marshall Space Flight Center (MSFC) has recognized the need for large electrical power systems (EPS's) in upcoming Spacecraft. The operation of the spacecraft depends on the EPS. Therefore, it must be efficient, safe, and reliable. In 1978, as a consequence of having to supply a large number of EPS personnel to monitor and control Skylab, the Electrical power Branch of MSFC began the autonomously managed power system (AMPS) project. This project resulted in the assembly of a 25-kW high-voltage dc test facility and provided the means of getting man out of the loop as much as possible. AMPS includes several embedded controllers which allow a significant level of autonomous operation. More recently, the Electrical Division at MSFC has developed the space station module power management and distribution (SSM/PMAD) breadboard to investigate managing and distributing power in the Space Station Freedom habitation and laboratory modules. Again, the requirement for a high level of autonomy for the efficient operation over the lifetime of the station and for the benefits of enhanced safety has been demonstrated. This paper describes the two breadboards and the hierarchical approach to automation which was developed through these projects.

Lollar, L. F.

Concept for a power system controller for large space electrical power systems

The development of technology for a fail-operatonal power system controller (PSC) utilizing microprocessor technology for managing the distribution and power processor subsystems of a large multi-kW space electrical power system is discussed. The specific functions which must be performed by the PSC, the best microprocessor available to do the job, and the feasibility, cost savings, and applications of a PSC were determined. A limited function breadboard version of a PSC was developed to demonstrate the concept and potential cost savings.

Lollar, L. F.