Asenkron Motor Rotor Arızalarının İstatiksel Analiz Yöntemi ile Değerlendirilmesi

Bu makalede sincap kafesli asenkron motorlarda yaygın olarak meydana gelen rotor arızalarının istatistiksel olarak analizi ve değerlendirilmesi yapılacaktır. Rotor arızaları genel olarak rotor çubuklarının kırılması ve kısa-devre halkasının çatlaması sonucu meydana gelir. Rotor arızaları stator akımına harmonik olarak yansımaktadırlar. Bu harmoniklerin tespiti için çeşitli sinyal işleme yöntemleri kullanılmaktır. Bu harmonikler ve diğer özellik çıkarım yöntemleri asenkron motor arızalarını tespit edilmesi için kullanılmaktadır. Bu çalışmada stator akımı önce zarf analizi ile incelenmiştir. Zarf analizi sonucu elde edilen veriler istatistiksel olarak incelenmiştir. İstatistiksel analizde ortalama, medyan, standart sapma, varyans, basıklık, çarpıklık, olasılık yoğunluk fonksiyonu ve kümülatif dağılım fonksiyonları hesaplanmıştır. Elde edilen sonuçlar istatistiksel analiz yöntemlerinin sincap-kafesli asenkron motorlarda rotor arızalarının incelenmesinde ve tespit edilmesinde kullanılabileceğini göstermektedir.

Evaluation of Rotor Faults of Induction Motors by Statistical Analysis Method

In this article, commonly occurring rotor faults of squirrel-cage induction motors will be statistically analyzed and evaluated. Rotor faults generally occur due to broken rotor bars and cracking of end-rings. Rotor faults are reflected into the stator current as harmonics. Various signal processing methods are used to detect these harmonics. These harmonics and other feature extraction methods are used to detect the faults of induction motor. In this work, the stator current is firstly studied by using envelope analysis. The data gained as result of Envelope analysis are studied statistically. In the statistical analysis mean, median, standard deviation, variance, kurtosis, skewness, probability density function and cumulative density function were calculated. The gained results indicate that the statistical analysis methods can be used for the detection of rotor faults of squirrel-cage induction motors.

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