The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The following topics are dealt with: electric machines; machine control; superconducting machines; electromagnetic shielding and electromagnetic compatibility; motor drives; power transformers and power supplies to apparatus.
This paper proposes a simplified thermal circuit to estimate the temperature rise in the winding of a totally enclosed fan cooled (TEFC) electric motor for different loads and/or cooling conditions since the motor has already been tested for a known condition. The differential of this circuit is the use of only two thermal resistances, one for the whole conduction and the other for the convection...
Stray losses outside of windings are a subject of numerous different analyses in the power transformer production industry. The purpose of this paper is to illustrate an approach that combines 3D finite element static magnetic field calculation and nonlinear mathematical programming in a single method derived to increase accuracy of stray losses estimation.
This paper shows a possibility to calculate and predict the sound radiation of electrical machines with the finite element analysis (FEA). Based on knowledge of analytical approaches, it is tried to show a possibility to calculate the noise emission of induction machines as a 2D-multi-physical problem with a more modern method. The influence of the machine housing relating to frequency spectrum is...
This paper presents a new modulation strategy control used to reduce the acoustic noise radiated by PWM-controlled induction machine drives and compares the measurements (and results) between a classical SPWM (sinusoidal pulse width modulation) and the new strategy HIPWM-FMTC (harmonics injections PWM and frequency-modulated triangular carrier) with a 1 KW induction machine with no load.
This paper introduces a software tool for the design of cage-rotor induction machines. The software covers electromagnetic dimensioning, thermal calculations and cooler design as well as mechanical calculations of critical speeds and natural stator frequencies.
A 3D finite element model is developed to simulate the load noise in order to understand the acoustic and mechanical behavior of power transformers. As we can show, a 3D model is required to get a good correlation between the simulation and measurements, because some resonant modes are not axisymmetric and the phases influence each other. To reduce the complexity of the model we investigated different...
In this paper, we advance results of an ongoing investigation related with the detection of static and dynamic eccentricity in cage induction motors fed by frequency converter using line current spectral analysis. A statistical analysis of the results obtained with the laboratory motors for different supply conditions has been carried out. These results allow us to present some preliminary conclusions.
Off-center of rotor in motors causes the noise and vibration. In this paper, the effects of various types of off-center of rotor on the dynamic characteristics of a miniature motor are estimated using the 3-D finite element method (3-D FEM).
The innovative insulating tape for rotating machines shows advantages concerning the electrical and mechanical strength as well as its thickness and thermal conductivity. In this paper the new developed mica tapes should be tested with respect to the thermal behaviour of the end corona protection and voltage endurance of various types of used mica paper. For this reason a test series of different...
During complex measurements on synchronous hydro-generator 35 MVA, among other measurements, temperature measurement of stator winding end was realized. The real aim of this temperature measurement was to determine influence of excitation winding on armature windings during different operation points. This paper describes the measurement procedure, measurement system and some problems that occurred...
This paper presents the results and conclusions on loss measurements of a 1 MW dual-stator synchronous motor with redundant voltage source inverter (VSI) drive. Measurements were performed on both 3-phase configuration with paralleled stator systems and 6-phase configuration with 30 degree phase shift between the stator systems (YY30). The results prove the applicability of YY30 configuration with...
The influence of various types of windings on the cogging torque and the total torque developed by a three-phase permanent magnet synchronous motor (PMSM) is investigated. The number of poles and rotor geometry are fixed and the stator slot number is modified. The finite element technique is used for the computation of the machine characteristic. The torque is determined by means of the Maxwell stress...
This paper presents an analysis of the environmental and life cycle costs of a switched reluctance motor (SRM) drive. The analysis was carried out according to the Energy-Using Product Directive (EuP 2005/32/EC) and following the Methodology for the Eco-Design of Energy-Using Products (MEEUP methodology). The base case model adopted is an 8/6 SRM with 1.5 kW of output power that can be considered...
In the late 1980s severe explosions of motors used on off shore oil platforms forced manufacturers of explosion protected electrical machines to make their products safer, although they were still built according to the latest standards. They started investigations that identified several features of design and operation of machines with negative influence on the explosion risk. The implementation...
High performance magnetic gears are competitive with mechanical gears in terms of their torque transmission capability, and they offer significant operational benefits. Various topologies of magnetic gear have been developed, the one which is described in this paper being particularly appropriate for use in applications for which a high gear ratio is required. It is the magnetic equivalent of a mechanical...
The paper presents the aspects regarding FEM analysis of a reluctant motor for direct driving of the light electric vehicles. The reluctant motor take into study is of special construction suitable for direct drive of a light electric vehicle. It is an inverse radial reluctant motor, with a fixed stator mounted on front wheel shaft and an external toothed rotor fixed on the front wheel itself. A short...
The paper comprehensively describes the design process of a 60 kW, 9000 rpm, totally enclosed, water cooled PM synchronous machine. PM machine technology is a rival choice for higher-speed applications ruled normally by traditional or solid-rotor induction machines. PM technology offers several advantages on higher-speed applications compared to IM solutions - a high torque density, small size and...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.