Search Results

Unlike a terrestrial electric utility which can purchase power from a neighboring utility, the Space Station Freedom (SSF) has strictly limited energy resources; as a result, source control, system monitoring, system protection and load management are essential to the safe and efficient operation of the SSF Electric Power System (EPS). These functions are being evaluated in the DC Power Management and Distribution (PMAD) Testbed which NASA LeRC has developed at the Power System Facility (PSF) located in Cleveland, Ohio. The testbed is an ideal platform to develop, integrate, and verify power system monitoring and control algorithms. State Estimation (SE) is a monitoring tool used extensively in terrestrial electric utilities to ensure safe power system operation.

The process of reducing a physical system to a mathematical representation is a prevalent task mutual to all fields of analysis. Sometimes the system of equations, or mathematical model as commonly known, will be modified on a trial and error basis to make the model respond in some predetermined fashion or react so as to match behavioral data obtained from the actual physical system. This paper presents a survey of activities to produce logically based schemes to generate mathematical models by making use of experimentally derived information. Primary attention is given to modeling of mechanical structures for purposes of dynamic analysis. Emphasis is given to current effort at Goddard and in particular to the recent studies designed to verify the practical effectiveness of a specific modeling scheme. Strengths and weaknesses of the various modeling schemes are discussed.