Type of Award: SBIR Phase I; Phase II Proposal Accepted by NASA LeRC but Rejected by NASA Headquarters Contract Number: NAS3-25119 Agency: NASA LeRC Status: Completed Period: 1/21/87 to 7/21/87 Principal Investigator: Paul Krause Abstract: Recent technical advancements in the semiconductor device and power conditioning technologies have led to substantial improvements in terms of size, weight, efficiency and power quality of the power conditioning equipment which is being considered for space applications. With these advancements comes an abundance of design choices and increased degrees of freedom with respect to power system control. These degrees of freedom may be used advantageously to develop control strategies which improve the reliability and dynamic characteristics of the integrated power system by making it less sensitive to possibly large and abrupt changes in load. There are two main objectives associated with the Phase I research effort. The first is to develop a highly detailed computer simulation of a power generation, conditioning and distribution system suitable for space applications. The second is to investigate several innovative control system techniques involving feed forward voltage control and load sharing strategies which are aimed at maintaining precise regulation during steady state and transient conditions. The viability and effectiveness of these strategies will be tested by incorporating them into the computer simulation of the integrated power system developed as part of the first...
Read MorePhase I: Control of Resonance in a 20-Khz Space Power System and Investigation of Advanced Power Sources (MSFC) and Phase II: Investigation of Advanced Power Sources and Actuator Systems for Future Aerospace Vehicles (LeRC)
Type of Awards: SBIR Phase I and Phase II Contract Numbers: NAS8-38035 and NAS3-25962 Agencies: Phase I: NASA MSFC and Phase II: NASA LeRC Status: Completed Periods: 12/29/88 to 5/29/89 and 8/31/90 to 8/30/92 Principal Investigators: Phase I: Paul Krause; Phase II: Scott Sudhoff Phase III: Power Systems Modeling for Power-By-Wire Applications; NAS3-27203 Abstract: In Phase I, detailed computer simulations of two candidate 20-kHz spacecraft power systems (TRW and GD) were implemented on a Hybrid Computer/Power Systems Simulator and verified by comparison with experimental results. In the absence of filtering, both systems exhibit harmonic resonances due to an interaction between the switching of the source converter and the ac system. Methods of suppressing harmonic resonance and improving the waveform quality were demonstrated in both power systems studied. The primary objective of the proposed Phase II research is to investigate power system configurations for use in future aerospace vehicles including spacecraft and the all-electric airplane. The power systems will be investigated on an end-to-end basis including the source(s), transmission/distribution system, load converters, and electromechanical actuators. The computer models that are to be developed in Phase II will provide a convenient means of comparing competing power system configurations from the standpoint of stability, regulation, harmonic distortion, and system interactions, all on an end-to-end system...
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