Energy Efficiency Improvement by Tap Adjustment in Transformer Using Genetic Algorithms

Öz

Main purpose in this study is to minimize the active power losses of the distribution systems as an optimization problem. To achieve this, the tap position of the ULTC (Under Load Tap Changer) is used as the system variable. As the processual flow of the method, the tap setting of the ULTC in the IEEE 13 Bus test system, was obtained by power flow with OpenDSS software according to the predetermined load condition for 24 hours, on the first step. The step value of the transformer's output voltage of the transformer is adjusted to the desired level (usually 1 per-unit (pu) in the middle point of the feeder), in OpenDSS software. In the next step, as the main objective, an implementation is designed in MATLAB to compute the transformer tap values, which will minimize the active power losses in distribution systems by using genetic algorithms which is a heuristic method. As a constraint, the voltage level in the system is kept between 0.95 - 1.05 pu. Simulation studies have shown, loss minimization provides more effectiveness and better energy efficiency by using the step values obtained by genetic algorithms.

Anahtar Kelimeler

• Energy efficiency
• Optimization
• Genetic algorithms
• Transformer tap changing

Genetik Algoritmalar Kullanılarak Transformatörde Kademe Ayarı ile Enerji Verimliliği İyileştirme

Öz

Bu çalışmada amaç, bir optimizasyon problemi olarak, dağıtım sisteminin aktif güç kayıplarını minimum yapmaktır. Bunun için, sistem değişkeni olarak kademe değiştiricili transformatörün kademe pozisyonu kullanılmıştır. Yöntem adımları olarak önce, IEEE 13 Baralı test sisteminde bulunan kademe değiştiricili transformatörün kademe ayarı, 24 saat için önceden öngörülen yük durumuna göre OpenDSS yazılımı ile güç akışı yapılarak elde edilmiştir. OpenDSS yazılımında kademe değeri transformatörün çıkış gerilimi istenilen seviyeye (genellikle fiderin tam ortasında 1 per-unit (pu) olacak şekilde) ayarlanmaktadır. Sonra esas amaç olan, dağıtım sistemindeki aktif güç kayıplarını minimum yapacak transformatör kademe değerleri MATLAB programında, sezgisel yöntemlerden olan genetik algoritmalar kullanılarak bulunmuştur. Kısıt olarak sistemdeki gerilim seviyesi 0.95 - 1.05 pu arasında tutulmuştur. Yapılan Simülasyon çalışmaları, genetik algoritmalarla elde edilen kademe değerleri ile kayıp minimizasyonun daha etkin daha iyi enerji verimliliği sağladığını göstermiştir.

Anahtar Kelimeler

• Enerji verimliliği
• Optimizasyon
• Transformatör kademe ayarı
• Genetik algoritmalar

Kaynakça

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