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One driving factor that is critical to aerospace power electronic systems is the reduction in weight and size. A key focus of power electronic building blocks (PEBB) is the reduction of size and weight and, hence, increased integration of power electronic systems. PEBB can be viewed as a three-port electronic module with input, output and control ports. This paper summarizes the results of a study undertaken by NASA Glenn Research Center to evaluate the insertion of PEBB into aerospace power electronic systems. It surveys the applications of power electronics in aerospace systems, and evaluates the capabilities and limitations of potential PEBB architectures for aerospace applications. It, also, constructs a road map to assist in formulating requirements and developing architectures for aerospace-based PEBB product development. Finally, it identifies follow-on work for detailed research to expedite first generation aerospace-based PEBB product developments.

This paper discusses the effects of variations in system parameters on the dynamic behavior of a Free-Piston Stirling Engine/Linear Alternator (FPSE/LA)-load system. The mathematical formulations incorporate both the mechanical and thermodynamic properties of the FPSE, as well as the electrical equations of the connected load. State-space technique in the frequency domain is applied to the resulting system of equations to facilitate the evaluation of parametric impacts on the system dynamic stability. Also included is a discussion on the system transient stability as affected by sudden changes in some key operating conditions. Some representative results are correlated with experimental data to verify the model and analytic formulation accuracies. Guidelines are given for ranges of the system parameters which will ensure an overall stable operation.

A test facility at NASA Lewis has been assembled for evaluating: free-piston Stirling engine/linear alternator control options, and interaction with various electrical loads. This facility is based on a “SPIKE” engine/alternator. The paper describes the engine/alternator, a multi-purpose load system, a digital computer based load and facility control, and a data acquisition system with both steady-periodic and transient capability. Preliminary steady-periodic results are included for several operating modes of a digital AC parasitic load control. Preliminary results on the transient response to switching a resistive AC user load are discussed.

This paper describes the results of studies related to conceptual topologies of an integrated utility-like space power system. The system topologies are comparatively analyzed by considering their transmission energy losses as functions of mainly distribution voltage level and load composition. The analysis is expedited by use of a Distribution System Analysis and Simulation (DSAS) software. This recently developed computer program by the Electric Power Research Institute (EPRI) uses improved load models to solve the power flow within the system. However, present shortcomings of the software with regard to space applications, and incompletely defined characteristics of a space power system make the results applicable to only the fundamental trends of energy losses of the topologies studied. Accountability, such as included, for the effects of the various parameters on the system performance can constitute part of a planning tool for a space power distribution system.