In this Letter we investigate factors that influence the effective critical electric field for runaway-electron generation in plasmas. We present numerical solutions of the kinetic equation and discuss the implications for the threshold electric field. We show that the effective electric field necessary for significant runaway-electron formation often is higher than previously calculated due to...

This paper presents a new concept for an active high voltage insulation system with dynamic and adaptive features. The governing principle is based on surface charge accumulation on dielectrically covered electrodes in air under atmospheric pressure. This accumulation results in a charge-induced electric field component which steers the field distribution within the system advantageously. At eq...

Abstract: This paper presents an on-board vehicular battery charger that integrates bidirectional AC/DC converter and DC/DC converter to achieve high power density for application in electric vehicles (EVs). The integrated charger is able to transfer electrical energy between the battery pack and the electric traction system and to function as an AC/DC battery charger. The integrated charger to...

Model for efficiency optimization of electric elevator drive is presented in this paper. It combines two strategies for efficiency optimization: Loss model control and Search control. Search control technique is used in a steady state of drive and loss model during transient processes. As a result, power and energy losses are reduced, especially when load torque is significant less related to i...

Hajime Urai, Dr. Eng. Takahide Matsuo Hiroaki Hashimoto Tatsuro Kato, Dr. Eng. OVERVIEW: The market for electric power transmission systems is expected to grow strongly, driven by growing demand for electric power in emerging economies and the adoption of renewable energy. Transformers, circuit breakers, and switchgear are important components of these electric power transmission systems. The e...

Experiments have been conducted on a dual electric grid thermionic device to investigate an alternative method of space charge mitigation in a thermionic energy convertor (TEC). Two electric grids, the attractor and deflector grids, provide opposing electric fields to overcome space charge while minimizing power losses to the attractor grid. Electron beams are formed in the electrode gap provid...

Various circuit technologies have been studied and developed. One of main streams concerns a soft switching technology to mitigate switching stress, leading to the reduction in switching losses or electro-magnetic noise. On the other hand, as a characterized orthodox technology, the existing chopper circuit is used for the electric vehicles, etc. Such technologies have a tendency to go out of v...

This master thesis deals with the design of an permanent magnet (PM) motor for electric vehicles. An analytical model for surface mounted PM-motors (SMPM) is derived and verified with finite element analysis (FEM). Special attention is paid to the iron losses as they influence the performances. Today's motors for traction in electric vehicles are most often induction motors. In recent years, PM...

Annual electricity distribution losses average 4% in the European Union. These losses represent 7 billion Euros in annual waste. New regulations are forcing electrical distributors to enhance efficiency across their networks. Network operators are also challenged to integrate alternative energy generation and electric vehicles into their grids. This paper offers a strategy for leveraging smart ...