LSTM Derin Öğrenme Ağı ile Dalga Enerjisi Dinamiklerinin Analizi ve Tahmini

Öz

Yenilenebilir enerjinin en avantajlı kaynaklarından biri okyanus akıntıları ve dalgalarıdır. Deniz ortamındaki enerji bulunabilirliğinin tahmini araştırmacılar tarafından kapsamlı bir şekilde ele alınan bir konudur. Literatürde çeşitli hava durumu tahmin yaklaşımları, sayısal modeller ve hatta yapay zekâ sistemleri incelenmektedir. Okyanus dalgası ve gelgit enerjisi dönüştürme ekipmanlarının deniz ortamında ne kadar iyi çalışacağının tahmin edilmesi, diğer konulara kıyasla daha az araştırılan bir konudur. Bu nedenle, ilk adım olarak şamandıra tipi bir güç alma (power take-off, PTO) cihazının rastgele bir deniz ortamındaki zamansal dinamiklerinin modellenmesi gerçekleştirilmiştir. Rastgele deniz ortamını temsil etmek için bir spektrum tekniği kullanılmış ve çok spektrumlu okyanus dalgası alanını verimli bir şekilde simüle etmek için FFT rutinleri kullanılmıştır. Transfer fonksiyonu yaklaşımı bu çok spektrumlu ortamda PTO cihazının dinamiklerini modellemek için kullanılmıştır. İkinci adım olarak, Uzun Kısa Dönemli Hafıza (Long Short Term Memory, LSTM) derin öğrenme ağı, düşey hızları ve dönüştürücü güç zaman serilerini tahmin etmek için kullanılmıştır. Anlık dönüştürücü gücü ve cihaz dinamiklerinin LSTM tarafından tahmin edilebileceği gösterilmiştir. Araştırmamıza göre, bu tür tahminler için LSTM tabanlı derin öğrenme veya benzeri teknikler kullanılabilir; bu da güç dönüşümünü en üst düzeye çıkarmada, rezonans dinamiklerini öngörmede, aşırı yükleme ve dönüştürücü yapısal hasarını önlemede yardımcı olabilir.

Anahtar Kelimeler

• Okyanus dalgaları
• dalga enerjisi
• LSTM

Analysis and Forecasting of the Wave Energy Dynamics via LSTM Deep Learning Network

Öz

One of the most advantageous sources of renewable energy is the currents and waves of the ocean. Predicting the energy availability in the maritime environment is a topic that has been extensively addressed by researchers. Various weather forecasting approaches, numerical models, and even artificial intelligence systems are examined in the literature. Predicting how well ocean wave and tidal energy converting equipment will operate in a marine setting is less frequently researched compared to other topics. For this reason, modeling the temporal dynamics of a buoy-type power take-off (PTO) device in a random marine environment is carried out as the initial step. A spectrum technique is used to represent the random sea environment, and FFT routines are used to efficiently simulate the multi-spectral ocean wave field. The transfer function approach is used to model the dynamics of a PTO device in this multi-spectral environment. As the second step, the Long Short Term Memory (LSTM) deep learning network is used to predict the heave velocities and converter power time series. It is demonstrated that the instantaneous converter power and device dynamics can be predicted by the LSTM. According to our research, LSTM-based deep learning or comparable techniques can be used for these kinds of forecasts, which could be helpful in maximizing power conversion, anticipating resonance dynamics, and preventing excessive loading and converter structural damage.

Anahtar Kelimeler

• Ocean waves
• wave energy
• LSTM

Kaynakça

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