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.
Dynamic rotor faults of induction machines as broken bars and rotor eccentricity cause dynamic changes in the rotor electromagnetic field and therefore also in magnetomotive force. These changes in the electromagnetic field cause motor current amplitude and phase modulation. The rotating electromagnetic field has not a stable angular frequency but oscillates around its angular frequency. The phase...
Demodulation techniques extract modulating currents induced by induction motors rotor faults and directly evaluate these fault currents in time and frequency domain. Vector representation of amplitude and phase modulation is analyzed with the investigation, how both modulations change with changing parameters. It is proved that fault indicators of amplitude modulation do not change with motor changing...
Dynamic rotor faults of induction motors, mainly broken or cracked rotor bars and dynamic rotor eccentricity, cause stator currents modulation. The detailed motor current analysis revealed meaningful phase modulation and its relation to amplitude modulation at increasing motor load and inertia load It is shown, that by increasing motor load mainly phase modulation increases and by increasing inertia...
Dynamic faults of induction machines cause modulation. The main frequencies of modulating signals are rotation frequency at dynamic eccentricity and slip pole frequency at broken rotor bars or frame. Demodulation methods increase resolution both in magnitude region and frequency region, facilitate and precise evaluation. The paper introduces the basics of envelope analysis and two demodulation methods...
Space transformation transfers 3 phase currents to one space (Parkpsilas) vector. Frequency component of space vector magnitude MagP2fl at 2fl is the basic diagnostic symptom. In the paper the analysis of possible cause of 3-phase current system unbalance due to stator faults are discussed and it is shown, that stator faults induce amplitude, phase or harmonic distortion unbalance. By comparing the...
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.