Induction machine diagnostics based on FFT analysis of current space vector

• Autorzy: Rusek J.
• Języki publikacji: EN

Abstrakty

EN

FFT analysis of one of the stator currents has become a standard procedure for diagnosing the state of an induction machine. In this procedure the harmonics are all as if positive. However, if the stator currents are aggregated to a space vector, a direction of rotation of complex harmonics is determinable. The sign of a harmonic conveys additional information, important for diagnostic purposses. The paper presents analyses of calculated currents, based on an FFT algorithm for two currents. As, typically, a machine is fed through three cables, two currents are sufficient to establish a space vector of stator currents. The space vector is a complex quantity which can be put into an FFT analysis. A developed software is fitted with graphical interface. Unlike traditional display, separate amplitudes of harmonics are displayed above and below a horizontal frequency axis. The harmonics rotating in positive direction are displayed above, and the others below the frequency axis. The software automatically indicates zones where the slot harmonics are expected. The algorithm for this is based on a specific harmonic balance model. Based on the frequency of a slot harmonic, the rotor speed is determined. Preliminary analyses are uncluded.

Słowa kluczowe

EN

induction machine; electric machine; diagnostics; FFT analysis; current space vector

PL

maszyna indukcyjna; diagnostyka maszyn elektrycznych; analiza FFT; wektor przestrzenny prądu

• Wydawca: Sieć Badawcza Łukasiewicz - Górnośląski Instytut Technologiczny
• Czasopismo: Maszyny Elektryczne : zeszyty problemowe
• Rocznik: 2011
• Tom: Nr 5(93)
• Strony: 1--6
• Opis fizyczny: Bibliogr. 8 poz., rys.

Twórcy

autor

Rusek J.

• AGH University of Science and Technology,

Bibliografia

• [1] Rusek, J.: Categorization of induction machines in current signature analysis Electrical Engineering, Archiv fuer Elektrotechnik, Heidelberg, Volume 84, Number 5, Decembcr 2002, pp. 265-273
• [2] Zieliński, T.: Od teorii do cyfrowego przetwarzania sygnałów. Wydział EAIiE AGH, Kraków, 2002
• [3] Sobczyk, T.: Analiza procesów stacjonarnych maszyn elektrycznych. ZN AGH, nr 654, El. i Mech. G. i. H. z. 97, Kraków 1977
• [4] Rusek. J.: Moment elektromechaniczny silnika asynchronicznego klatkowego w stanie pracy ustalonej. Praca doktorska, AGH, Kraków, 1978
• [5] Rusek J.: Category, słot harmonics and the torąue of induction machines COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering. Volume 22, Number 2, 2003, pp. 388- 409
• [6] Elawgali S.: Diagnosing of rotor eccentricity and clutch wobbling of the induction machines, based on inspection of spectrums of the calculated and registered currents. Dissertation, AGH, Kraków, 2007
• [7] Stefani A., Filippetti F., Bellini A.: Diagnosis of induction machines in time-varying conditions 6th IEEE Int. Symposium on Diagnostics for Electric Machines, Power Electronics and Drives, SDEMPED 2007, Cracow, September 6-8, Proc. pp.126-131
• [8] Rusek J.: Diagnostic information contained in inter-harmonics of a direct and PWM supplied induction machine. International Conference on Renewable Energy and Power Quality. Santander, 12-14 of March, 2008, Proc. pp. 103-104