Volume 4, No. 11 (2005)

THE ELECTRICAL ASYNCHRONOUS MOTOR 2EDK04-110Y5 TYPE.FAULTS AND SOLUTIONS FOR THE INCREASING OF RELIABILITY; MEASURES ADOPTED FOR REPAIR`S PERFORMANCE

ANTIP MIHAIL, BORBEA CRISTINEL, RUSU TUDOR

The present work pretends to be a general guide for the repairers, but also for the users of electrical asynchronous motor 2EDK04-110Y5 types.Electrical asynchronous motor 2EDK04-110Y5 type fit out equipments used in the coal extractive industry in Romania, equipments which have foreign provenience (Russia).The importance of these engines, from the point of view of the equipment’s working, the complexity and the specific constructive characteristics, the utilization condition’s in activity, the inaccessibility for the professionals in Romania of such a specific technical information, determined S.C. Electro-Service S.R.L. Bacau, to achieve a detailed research in this field.This research accumulated theoretical and technical information – presented in the machine’s book; practical information – noticed from the motors which had arrived to the reparation; utilization terms - from the users, accumulated by them in time, through the machine’s utilization, the knowledge of extractive work specific conditions, the observations of machine behavior in working and the defects which appeared at the motor.All those information was described, in a technical seminary organized by the S.C. Electro-Service S.R.L. Bacau. Among the participants were experts from the users branch, but also experts from academical environments with experience in electrical machine designing.Through this study, S.C. Electro-Service S.R.L. Bacau wanted and managed to establish a certain solution accepted by both sides, solution which fulfill the requirements of quality and reliability requested by the customers.

MODELLING AND EMTP SIMULATION OF THE NON-LINEAR AND PARAMETRICAL CIRCUITS TO THE ELECTRICAL POWER QUALITY EVALUATION

BARABOI A., ADAM M., PANCU C.

It analyses the different non-linear and parametrical elements and circuits models and the possibilities of their simulation using EMTP software. It puts in evidence the characteristics of the simulation in EMTP, for each circuit model analyzed and the possibilities to using the results to the electrical power quality evaluation. In paper applications and numerical results are presented, obtained using the programs realized by the authors.

THE FREQUENT POWER TRANSFORMER’S DEFAULTS AND THE ABNORMALLY CONDITIONS OF WORKING. CAUSES AND REPARATIONS FOR EXTENDING THEIR LIFETIME

BORBEA CRISTINEL, RUSU TUDOR, ANTIP MIHAIL

This work will intend to present the default who appear at the oil transformers and their way of reparations based on the accumulated experience in the workshop of transformer’s reparations from S.C. Electro-Service S.R.L. Bacãu.

THE STATISTIC CHARACTER OF THE SHORT-CIRCUIT CURRENTS STRESSES

NEMEŞ CIPRIAN, IVAS DUMITRU

Knowing the thermal and electro-dynamic stresses is crucial to a safe design of equipment and power system components, manufacturing and other key industries but the subject generally does not receive the proper attention in engineering probabilistic design.The magnitude of these stresses depends directly on the short-circuit currents and the fault time and indirectly on the structural system characteristic and state just prior to the fault, thetype of fault, etc. These components affecting the magnitude of the thermal and electrodynamic stresses may be assumed as random variables, so, in order to take in account these parameters in stress analysis, the probabilistic approach will be a new way to explore the engineering design.

ASPECTS CONCERNING THE ELECTROMAGNETIC PRINT DETERMINATION OF THE ELECTRIC DEVICE

POPA SORIN, PUIU GABRIEL PETRU

The present work deals with the problem concerning the electromagnetic print determination of some different electric devices. So, we suggest the building of a scanner which could carry an electromagnetic field detector and, in the same time, serving of an acquisition plate, to be possible the command both of the scanner displace and the acquisition in real time of the values of the electromagnetic field produced by the device.

THE MODELLING AND THE SIMULATION OF THE INFLUENCE OF THE ELECTROMAGNETIC FIELD PRODUCED BY THE ENSEMBLE: SWITCH-SEPARATOR ON THE HUMAN BODY

PUIU GABRIEL PETRU, POPA SORIN

The present work shows the modelling and the simulation results of a situation in which one human being is subdued to the influence of an electromagnetic field generated by a working ensemble switch-separator.For making possible the construction of the ensemble switch-separator and of the human model, too, it is necessary to make a simplified model in Solid Works.The simulation of the electromagnetic field is possible only with the analyze in AC Magnetic in COSMOS EMS, by following the materials’ features and technical specifications of the equipment in debate. It obtains the diagrams and the graphics of the current density and of the inducted current.

THE CONSTRUCTIVE ELEMENT CALCULUS OF THE "IN CASING" CONTINUOS CURRENT ELECTROMAGNET’S COIL

RUSU TUDOR, ANTIP MIHAIL, BORBEA CRISTINEL

This paper include the theortical considerations, the stage of constructive element calculus of the "in casing" continuous current electromagnet’s coil and discussion concerning the factors that influence the working of these equipments. This paper is based on concrete case studies that was met in repair operation of "in casing" electromagnet in Electro-Service S.R.L. Bacau, for equipments used to elevate and transport. This paper is useful to the engineers who design, use and repair thus equipments.