Analog computer simulation of a DC-to-DC flyback converter.
DC to DC flyback converter stability problem studied by analog computer simulation, noting nonlinearities effects
Babaa, I. M. H.↗
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Non-dissipative DC to DC regulator converters.
Nondissipative DC to DC regulator converter electrical design criteria and circuit development for satellite solar power source system
Raposa, F. L.↗
Isolated, multiple-output voltage dc-to-dc converter
Isolated, multiple output voltage dc-to-dc converter provides power for television transmitter used in space vehicles. The isolation is accomplished by using a single-end switching transformer circuit. The converter is completely solid state.
Source record↗
Modification of dc-dc converters Final report
Design, modifications, and testing of dc-dc converter
Source record↗
DC to DC converter regulated by a constant- frequency duty-cycle generator.
Closed loop regulated flyback DC to DC converter using constant frequency generator for duty cycle control
Babaa, I. M. H.↗
Design and performance analysis of a medium- power dc-dc converter
Design and performance of dc-dc converter compatible with pulse width modulation inverter
Birchenough, A. G.↗
Positive dc to positive dc converter Patent
Conversion of positive dc voltage to positive dc voltage of lower amplitude
Berry, E. H.↗
Positive dc to negative dc converter Patent
Converting output of positive dc voltage source to negative dc voltage across load with common reference point
Berry, E. H.↗
A design for thick film microcircuit dc-to-dc converter electronics
Thick film microcircuit DC-TO-DC converter electronics design for TOPS spacecraft power subsystem
Capodici, S.↗
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.↗
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.↗
Linearized stability analysis and design of a flyback dc-dc boost regulator.
Analytic expressions for the small-signal power-stage describing functions of a switched dc-dc boost regulator are derived from an approximate continuous circuit model which is developed by a time-averaging technique. Closed-loop stability is attained through the design of frequency compensation of the loop gain. Open- and closed-loop regulator output impedances are derived from the linearized models for the given configuration. The analysis and design are compared with and confirmed by breadboard measurements.
Wester, G. W.↗
Regulated dc-to-dc converter for voltage step-up or step-down with input-output isolation
A closed loop regulated dc-to-dc converter employing an unregulated two winding inductive energy storage converter is provided by using a magnetically coupled multivibrator acting as duty cycle generator to drive the converter. The multivibrator is comprised of two transistor switches and a saturable transformer. The output of the converter is compared with a reference in a comparator which transmits a binary zero until the output exceeds the reference. When the output exceeds the reference, the binary output of the comparator drives transistor switches to turn the multivibrator off. The multivibrator is unbalanced so that a predetermined transistor will always turn on first when the binary feedback signal becomes zero.
Feng, S. Y.↗
ASDTIC control and standardized interface circuits applied to buck, parallel and buck-boost dc to dc power converters
Versatile standardized pulse modulation nondissipatively regulated control signal processing circuits were applied to three most commonly used dc to dc power converter configurations: (1) the series switching buck-regulator, (2) the pulse modulated parallel inverter, and (3) the buck-boost converter. The unique control concept and the commonality of control functions for all switching regulators have resulted in improved static and dynamic performance and control circuit standardization. New power-circuit technology was also applied to enhance reliability and to achieve optimum weight and efficiency.
Schoenfeld, A. D.↗
Digital computer simulation of inductor-energy-storage dc-to-dc converters with closed-loop regulators
The simulation of converter-controller combinations by means of a flexible digital computer program which produces output to a graphic display is discussed. The procedure is an alternative to mathematical analysis of converter systems. The types of computer programming involved in the simulation are described. Schematic diagrams, state equations, and output equations are displayed for four basic forms of inductor-energy-storage dc to dc converters. Mathematical models are developed to show the relationship of the parameters.
Ohri, A. K.↗
Noise reduction programs for DC-8 and DC-9 airplanes
A summary review is presented of the results of current and recently completed noise-reduction programs for DC-8 and DC-9 airplanes. The relationship of these programs to other efforts by Douglas to develop quieter CTOL airplanes is briefly outlined. The engine/nacelle concepts studied were: (1) application of nacelle acoustic treatment, (2) variable-area exhaust nozzles, (3) jet exhaust noise suppressors, and (4) engines with larger-diameter new front fans. Acoustic analyses leading to the selection of certain engine/nacelle configurations are described, as well as design constraints which limit the noise reduction capability of certain designs. Acoustic design features of the modified engine/nacelles are discussed along with estimates of the changes in aircraft community noise levels, as well as estimates of the changes in aircraft weight, performance, cost, and operational restrictions.
Frasca, R. L.↗
Efficiency and weight of voltage multiplier type ultra lightweight dc-dc converters
An analytical and experimental study was made of a capacitor-diode voltage multiplier without a transformer which offers the possibility of high efficiency with light weight. The dc-dc conversion efficiencies of about 94 percent were achieved at output powers of 150 watts at 1000 volts using 8x multiplication. A detailed identification of losses was made, including forward drop losses in component, switching losses, reverse junction capacitance charging losses, and charging losses in the main ladder capacitors.
Harrigill, W. T., Jr.↗