Yusuf OYSAL, Etem KÖKLÜKAYA, A. Serdar YILMAZ

Dinamik dalgacık ağların yük frekans denetimine uygulanması

Frekans kararlılığı açısından iki veya daha fazla sayıda güç bölgesi içeren enterkonnekte güç sistemlerinde, her bir bölgedeki üretim planlı bir güç alışverişini sürdürebilmek için gereklidir. Bu çalışmada içerisinde geri dinamikleri, ortogonal olmayan ana dalgacık aktivasyon fonksiyonları ve iç bağlantı ağırlıkları bulunan bir "Dinamik Dalgacık Ağı 'na (DDA) " dayalı yeni bir uyarlamak yük frekans denetleyicisi (YFD) tasarımı amaçlanmıştır. Bunun için bir DDA iki bölgeli bir güç sistemi örneğinde bölgeler arasına bağlanmıştır. Adaptasyon, DDA parametrelerinin ayarlanmasına dayanır. Bu da yük frekans hata masraflarını içeren bir ölçütün en aza indirilmesi ile sağlanır. Gerekli olan ölçütün ağ parametrelerine göre gradyanları, ek duyarlılık analizi ile hesaplanmıştır. Yapılan benzetim çalışmaları, bu denetim yaklaşımının geleneksel integral denetime göre daha başarılı olduğu bir iki bölgeli güç sistemi üzerinde göstermiştir.

Application of dynamics wavelet networks to load frequency control

Frequency stability is one of the stability criteria for large-scale stability of power system. In interconnected power systems with two or more areas, the generation within each area has to be controlled so as to maintain scheduled power interchange. Load frequency control scheme has two main control loops such as primary and secondary control. In primary loop, a steady state frequency error can occur forever. Secondary loop controls the active power at the tie line between areas. This paper proposes a new adaptive load frequency controller based on a "Dynamic Wavelet Network (DWN)" that has lag dynamics, non-orthogonal mother wavelets as activation function and interconnection weights. A DWN is connected between the two area power systems. The input signals of the DWN are the ACEs and their changes. The outputs of the DWN are the control signals for the two-area load frequency control. Adaptation is based on adjusting parameters of DWN for load frequency control. This is done by minimizing the cost functional of load frequency errors. The cost gradients with respect to the network parameters are calculated by adjoint sensitivity method. It is illustrated that, this control approach is more successful than conventional integral controller for load frequency control in two area systems.

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