9818246814

Zeszyły Problemowe - Maszyny Elektryczne Nr 86/2010

Barbara Górnicka, Lech Górecki Instytut Elektrotechniki, Wrocław

CHARAKTERYSTYKA ELEKTROIZOLACYJNEGO LAKIERU NASYCAJĄCEGO O ULEPSZONYCH WŁAŚCIWOŚCIACH

CHARACTERIZATION OF THE IMPREGNATING VARNISH WITH IMPROVED PROPERTIES

Abstract: The results of imestigation under dcveloping modem '"corona resistant" impregnating vamishes are presented. The better properties. especially improved resistance to pulse voltage coming from PWM imerter was achieved by ineorporation of nanofiller to standard polyestroimide vamish using the special elaborated procedurę. The nanocomposite vamish shows the durability under pulse yoltage above 20 times longer compared to the standard vamish and also the better bond strength. lesser water absorption and high thermal endurance. The discussion of phenomena tliat appeared in the nanostructurcd materiał is also presented.

Maria J. Zielińska, Wojciech G. Zieliński Politechnika Lubelska, Lublin

OPRACOWANIE ALGORYTMÓW REGULACJI NAPIĘCIA ZASILANIA WYSOKOOBROTOWYCH SILNIKÓW KLATKOWYCH CELEM ZAPEWNIENIA ZADANEGO MOMENTU KRYTYCZNEGO LUB ROZRUCHOWEGO

DEVELOPING ALGORITHMS FOR REGULATING THE SUPPLY VOLTAGE OF SQUIRREL-CAGE HIGH-SPEED MOTORS IN ORDER TO OBTAIN THE GIVEN BREAKDOWN OR STARTING TORQUE

Abstract: Obtaining a high value of the breakdown or starting torąue in an asynchronous motor is a very im-portant issue from the point of view of improving its opcrational properties. These values can be determined based on data of a typical equivalent scheme. This refers to motors without the skin effect in the cage bar or those in which the phenomenon has been omitted.

In a high-speed motor, the phenomena of core saturation and skin effect influence the parameters of the equivalent scheme. which are not constant values and depend on the frequency of supply voltage and the value of the current in the bar of the rotor’s cage. In consequence. an equivalent scheme valid for classic motors should not be used for analysis of the performance of a high-speed motor.

Based on an eqiuvalent scheme which takes into account the influence of frequeney on its parameters. the ar-ticle describes how supply voltage was selected in order to guarantee the prcsen ation of the given breakdow n or starting torque. The calculations were madę for threc motors rcpresenting Iow, medium and liigh power machines.

Maria J. Zielińska, Wojciech G. Zieliński Politechnika Lubelska, Lublin

METODA WYZNACZANIA POŚLIZGOWYCH CHARAKTERYSTYK ADMITANCJIWYSOKOOBROTOWEGO SILNIKA KLATKOWEGO

A METHOD OF DETERMINING THE SLIPPING CHARACTERISTICS OF AMITTANCE OF A SQUIRREL-CAGE HIGH-SPEED MOTOR