Time Delay Margins Computation for Stability of Hybrid Power Systems

Yıl 2020, Cilt: 23 Sayı: 4, 1131 - 1139, 01.12.2020

Halil Erol , Saffet Ayasun

https://doi.org/10.2339/politeknik.593892

Cited By: 2

Öz

In load frequency control (LFC), it is essential to
transmit measurements of control signals from the control center to plant side
and remote terminal units (RTU) to control center. Therefore, time delays
become inevitable due to the use of conventional communication channels. The
dynamic performance of LFC system would be degraded by these delays.   This paper is dedicated to the
delay-dependent stability of the LFC of hybrid power generation subsystem. The
system studied includes wind turbine generator (WTG), photovoltaic system (PV),
ultra-capacitor (UC) bank for energy storage, fuel cell (FC) system and diesel
generator(DG). Delay margin is stated for the upper bound on the delay for
stability of LFC system. An analytical method is used to compute delay margins.
Delay margins are calculated for wide range of proportional-integral (PI)
controller. Such results could be utilized to tune the PI controllers as to
achieve a compromise between the dynamic performance and the delay margin. It
has been determined in which intervals, the controller parameters of the
proposed hybrid system can be selected while the system is in stable region.
the results are presented in tables and graphs. Simulation study of the
proposed system with Matlab / Simulink was performed. The results of the
simulation studies and the theoretical studies showed compatibility. Simulation
studies verify the effectiveness of the proposed method.

Anahtar Kelimeler

Delay-dependent stability, delay margin, electrical power systems stability, load frequency control

Melez Güç Sistemlerinde Zaman Gecikmesinin Kararlılık Analizi

Öz

Yük frekans
kontrolü (LFC) de, kontrol sinyallerinin ölçümlerini kontrol merkezinden
kontrol ünitesine ve uzak terminal ünitelerinden (RTU) kontrol merkezine
iletmek esastır. Bu nedenle, geleneksel iletişim kanallarının kullanılması
nedeniyle zaman gecikmeleri kaçınılmaz hale geliyor. LFC sisteminin dinamik
performansı bu gecikmelerle azalır. Bu makale, yerel melez enerji üretim  sisteminin LFC'sinin gecikmeye bağlı
kararlılığını analiz etmektedir. Çalışılan sistem, rüzgar türbini jeneratörü
(WTG), fotovoltaik sistem (PV), enerji depolama için ultra-kapasitör (UC)
bankası, yakıt hücresi (FC) sistemi ve dizel jeneratör (DG) içerir. Bu
çalışmada, böyle bir sistemin modellemesi ve benzetimi yapılmıştır. Gecikme
marjı, LFC sisteminin kararlılık gecikmesinde üst sınırı belirtmektedir.
Gecikme marjlarını hesaplamak için analitik bir yöntem kullanılmıştır. Gecikme
marjları, oransal- integral (PI) kontrolörün geniş bir aralığı için
hesaplanmıştır. Bu sonuçlar, PI kontrolör parametrelerini, sistemin dinamik performansı
ile gecikme marjı arasında dengeli bir seçim yapacak şekilde ayarlamak için
kullanılabilir. Önerilen hibrit sistemin kontrolör parametrelerinin kararlılık
çerçevesinde hangi aralıklarda seçile bilineceği tespit edilerek, tablo ve
grafik halinde sunulmuştur. Önerilen sistemin Matlab/Simulink ile bezetim
çalışması gerçekleştirilmiştir. 
Simülasyon çalışmaları ile teorik çalışmaların sonuçları uyumluluk
göstermiştir. Simülasyon çalışmaları önerilen yöntemin etkinliğini
doğrulamaktadır.

Anahtar Kelimeler

Gecikmeye bağlı stabilite, gecikme marjı, elektriksel güç sistem kararlılığı, yük frekans kontrolü

Kaynakça

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