Converter design techniques and applications

Transistorized direct current voltage converters offer a number of advantages over other types because of their small size, low weight, high efficiency, high reliability, precision accuracy and wide range of control. There are three basic types of converter subsystems: series converter in which a voltage-controlled component is placed in series with the load; shunt converter in which a current-controlled component is placed in shunt with the load; and a switching converter in which a voltage-controlled component is turned on and off in series with the load. Converters employing any of these three types of subsystems can provide constant voltage, constant current, or constant impedance across the load. Design and application considerations, step-by-step design procedures, and the solution to sample design problems for the series, shunt, and switching types are presented

Index to nasa tech briefs, issue number 2

Annotated bibliography on technological innovations in NASA space program

The 30-cm ion thruster power processor

A power processor unit for powering and controlling the 30 cm Mercury Electron-Bombardment Ion Thruster was designed, fabricated, and tested. The unit uses a unique and highly efficient transistor bridge inverter power stage in its implementation. The system operated from a 200 to 400 V dc input power bus, provides 12 independently controllable and closely regulated dc power outputs, and has an overall power conditioning capacity of 3.5 kW. Protective circuitry was incorporated as an integral part of the design to assure failure-free operation during transient and steady-state load faults. The implemented unit demonstrated an electrical efficiency between 91.5 and 91.9 at its nominal rated load over the 200 to 400 V dc input bus range

Cumulative index to NASA Tech Briefs, 1963-1965

Annotated bibliography of NASA technical briefs on electrical, energy sources, materials, life sciences, and mechanical informatio

Design and implementation of a transistorized bi-controlled based utility-connected battery charger for underdeveloped nations

This paper presents a transistorized bi-controlled based utility-connected battery charger to address the problem of erratic public power supply in underdeveloped nations. In this study, a utility battery charger was built by the integration of grid power supply, line frequency transformer, power electronic switches, alternating current-direct current bridge converter, regulator, and resistor-inductor-capacitor. The excess-voltage protection and battery monitoring were obtained by the bi-controlled technique. In contrast to other charging systems in underdeveloped nations, the proposed system is very simple, rugged, reliable and cheap to maintain due to simplicity and un-programmed nature of the system. The results showed that the proposed system is craggy and robust to resist voltage stress, highly reliable and relatively free from leakage currents due to the presence of a double controlled scheme using a common point of action and a line frequency transformer. In addition, the system can be used to charge batteries ranging from 50μA and above. The system can be utilized in communication companies, electric vehicles, drilling machines

Research on spacecraft electrical power conversion

The history of spacecraft electrical power conversion in literature, research and practice is reviewed. It is noted that the design techniques, analyses and understanding which were developed make today's contribution to power computers and communication installations. New applications which require more power, improved dynamic response, greater reliability, and lower cost are outlined. The switching mode approach in electronic power conditioning is discussed. Technical aspects of the research are summarized

Electronic integration of the uk-1 international ionosphere satellite

Electronic integration of international ionosphere satellit

Extended performance electric propulsion power processor design study. Volume 2: Technical summary

Electric propulsion power processor technology has processed during the past decade to the point that it is considered ready for application. Several power processor design concepts were evaluated and compared. Emphasis was placed on a 30 cm ion thruster power processor with a beam power rating supply of 2.2KW to 10KW for the main propulsion power stage. Extension in power processor performance were defined and were designed in sufficient detail to determine efficiency, component weight, part count, reliability and thermal control. A detail design was performed on a microprocessor as the thyristor power processor controller. A reliability analysis was performed to evaluate the effect of the control electronics redesign. Preliminary electrical design, mechanical design and thermal analysis were performed on a 6KW power transformer for the beam supply. Bi-Mod mechanical, structural and thermal control configurations were evaluated for the power processor and preliminary estimates of mechanical weight were determined

Speech Communication

Contains research objectives and three research projects.U. S. Air Force (Electronic Systems Division) under Contract AF 19(604)-6102National Science Foundation (Grant G-16526)National Institutes of Health (Grant MH-04737-02

Cumulative Index to NASA Tech Briefs, 1963 - 1966

Cumulative index of NASA Tech Briefs dealing with electrical and electronic, physical science and energy sources, materials and chemistry, life science, and mechanical innovation