Topic
Propulsion
About: Propulsion is a research topic. Over the lifetime, 24977 publications have been published within this topic receiving 200311 citations.
Papers published on a yearly basis
Papers
More filters
02 Apr 2007
TL;DR: In this article, the current range of advanced IGBT propulsion inverters used in railways from light rail vehicles to high speed trains and locomotives is described and future trends in IGBT railway propulsion drives are discussed.
Abstract: This paper describes the current range of advanced IGBT propulsion inverters used in railways from light rail vehicles to high speed trains & locomotives. The second part of the paper describes future trends in IGBT railway propulsion drives. One such trend is the concept of power integration which leads to weight, volume and cost reduction . Finally, for systems with an AC input supply, a concept for reducing the weight of the main input transformer is also described. This uses a configuration of resonant converter and a medium frequency transformer , the so called e-transformer, and could be particularly targeted for 15 kV, 16.7 Hz supplied systems.
72 citations
TL;DR: In this paper, the recent achievements and future outlook in the field of photonic space propulsion are outlined, and some of the key challenges in the area and possible solutions for practical applications are discussed.
Abstract: An abundant source of energy in space, electromagnetic radiation can provide spacecraft with a gentle yet persistent thrust for interplanetary and interstellar missions. Early successes with microlaser and solar propulsion platforms confirm their potential for near-Earth and deep space exploration, although practical realization of reliable photonic devices is not trivial. This Perspective outlines the recent achievements and future outlook in the field of photonic space propulsion. We highlight several light-enabled mechanisms of thrust generation via photon–matter interactions such as photonic pressure and ablation, optical gradient forces, light-induced electron emission and others. Finally, we outline some of the key challenges in the area and possible solutions for practical applications. Recent achievements and future opportunities for light as a propulsion scheme for space vehicles is discussed.
72 citations
TL;DR: The findings of this paper conclude that a purely ac synchronous network performs best in terms of mass and efficiency, but similar levels of functionality and controllability to an architecture with electrical decoupling via dc cannot readily be achieved.
Abstract: Turbine-engine-driven distributed electrical aircraft power systems [also referred to as turboelectric distributed propulsion (TeDP)] are proposed for providing thrust for future aircraft with superconducting components operating at 77 K, in order for performance and emission targets to be met. The proposal of such systems presents a radical change from current state-of-the-art aeroelectrical power systems. Central to the development of such power systems are architecture design trades which must consider system functionality and performance, system robustness, and fault ridethrough capability, in addition to the balance between mass and efficiency. This paper presents a quantitative comparison of the three potential candidate architectures for TeDP electrical networks. This analysis provides the foundations for establishing the feasibility of these different architectures subject to design and operational constraints. The findings of this paper conclude that a purely ac synchronous network performs best in terms of mass and efficiency, but similar levels of functionality and controllability to an architecture with electrical decoupling via dc cannot readily be achieved. If power electronic converters with cryocoolers are found to be necessary for functionality and controllability purposes, then studies show that a significant increase in the efficiency of solid-state switching components is necessary to achieve specified aircraft performance targets.
72 citations
TL;DR: In this article, a review of hybrid rocket engines state of the art was performed, together with a detailed analysis of the possible applications of such a technology, taking into account the needs of industrial applications of this technology.
72 citations
21 Jun 1998
TL;DR: A research effort is discussed that addresses the design and implementation of a formation flight system that is capable of truly infinite endurance and the difficulties involved in the autonomous control of such systems.
Abstract: It has long been known that aircraft flying in close formation can achieve an overall efficiency much greater than is possible for each aircraft flying alone. When coupled with possible near-term advances in solar-electric power storage and aeronautical propulsion systems, it is theoretically possible to create a formation flight system that is capable of truly infinite endurance. This paper discusses a research effort currently underway that addresses the design and implementation of such a system. A brief overview of the system concept is given, and some of the particular problems inherent are more fully discussed. In particular, the difficulties involved in the autonomous control of such systems are presented and discussed.
72 citations