Güç Kalitesi Bozulmalarının 2 Boyutlu Ayrık Dalgacık Dönüşümü ve Torbalama Karar Ağaçları Yöntemi ile Sınıflandırılması

Öz

Bu çalışmada, Güç Kalitesi (GK) bozulmalarının sınıflandırılması için 2 Boyutlu Ayrık Dalgacık Dönüşümü (2B-ADD) yöntemi ile öznitelikler çıkartılmakta ve Destek Vektör Makineleri (DVM), Yapay Sinir Ağları (YSA) ve Torbalama Karar Ağaçları (TKA) yöntemleri ile sınıflandırma işlemi yapılmaktadır. Gürültülü (40 dB, 30 dB ve 20 dB) ve gürültüsüz durumları içeren 11 farklı GK bozulması için toplamda 2200 adet sinyal sentetik olarak üretilmektedir. Sinyaller 2 boyutlu görüntü matrislerine çevrilmekte ve her birine 2B-ADD uygulanmaktadır. Farklı ayrıştırma seviyesi ve istatistiksel özellikler uygulanarak öznitelikler oluşturulmaktadır. Özniteliklerden en uygun olanları Sıralı İleri Seçim (SİS) ve ReliefF yöntemleri ile seçilmektedir. Benzetim çalışmasına göre 3 farklı sınıflandırıcının başarımı birbirleri ile kıyaslanmaktadır. Sıralı ileri seçim ile seçilen öznitelikleri kullanan TKA yönteminin %99.12±0.12 oranı ile en iyi başarımı veren yöntem olduğu görülmektedir.

Anahtar Kelimeler

• Güç kalitesi,2 boyutlu ayrık dalgacık dönüşümü,torbalama karar ağaçları sınıflandırıcısı,sıralı ileri seçim,ReliefF

Classification of Power Quality Disturbances with 2D Discrete Wavelet Transform and Bagged Decision Trees Method

Öz

In this study, to classify Power Quality (PQ) disturbances, attributes are extracted by 2D Discrete Wavelet Transform (2D-DWT) method and Support Vector Machines, Artificial Neural Networks and Bagged Decision Trees (BDT) methods are used for classification stage. 2200 signals are synthetically produced for 11 different PQ disturbances, including noisy (40 dB, 30 dB and 20 dB) and noiseless states. Signals are transformed into 2D image matrices and 2D DWT is applied to each. Attributes are created by applying different level of decomposition and statistical properties. The most appropriate ones are selected with Sequential Forward Selection (SFS) and ReliefF methods. BDT method, which uses selected attributes with SFS, is the method that gives the best performance with a rate of 99.12±0.12%.

Anahtar Kelimeler

• Power quality,2D discrete wavelet transform,bagged trees classifier,sequential forward selection,ReliefF

Kaynakça

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