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Feng, S. Y. M.

Publications and source records attributed to Feng, S. Y. M..

7 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1971

Very-high-frequency dc-to-dc conversion and regulation in the low-megahertz range.

Anticipated new mission requirements have motivated research on very-high-frequency (VHF) regulated dc-to-dc converters to operate at conversion frequencies in the low-megahertz range. State-of-the-art electronic components for VHF operation are discussed. Two different converter configurations, one using proportional control and having a conversion frequency of 0.1 MHz and the other using bistable control and having a conversion frequency of 3.8 MHz, are presented to indicate converter performance in this VHF region. Converter losses, which are of prime importance at these frequencies, are discussed and possible means of reducing these losses are suggested.

Feng, S. Y. M.↗
NASA NTRS1971

Regulated dc-to-dc converter for voltage step-up or step-down with input-output isolation.

A dc-to-dc regulated-converter circuit employing duty-cycle control with variable on and variable off time has been presented. A unique feature of this converter is the method by which the bistable-comparator output controls the duty cycle of the power switching transistor through the action of the encoder. The utilization of minor-loop flux excursions of a saturable-core transformer in the encoder makes it feasible to extend the converter switching frequency considerably higher than would normally be possible. With this converter circuit, high and very-high frequency converter operations were explored.

Feng, S. Y. M.↗