An Intrusion Detection System (IDS) is a tool used primarily for security monitoring, which is one of the security strategies for Supervisory Control and Data Acquisition (SCADA) systems. Distributed Network Protocol version 3 (DNP3) is the predominant SCADA protocol in the energy sector. In this paper, we have developed an effective and flexible IDS for DNP3 networks, observing that most critical operations in DNP3 systems are utilized based on the function codes in DNP3 application messages, and that exploitation of those function codes enables attackers to manipulate the system operation. Our proposed anomaly-detection method deals with possible attacks that can bypass any rule-based deep packet inspection once attackers take over servers in the system. First, we generated datasets that reflected DNP3 traffic characteristics observed in real-world power grid substations for a reasonably long time. Next, we extracted input features that consisted of the occurrences of function codes per TCP connection, along with TCP characteristics. We then used an unsupervised deep learning model (Autoencoder) to learn the normal behavior of DNP3 traffic based on function code patterns. We called our approach FC-AE-IDS (Function Code Autoencoder IDS). The evaluation of the proposed method was carried out on three different datasets, to prove its accuracy and effectiveness. To evaluate the effectiveness of our proposed method, we performed various experiments that resulted in more than 95% detection accuracy for all considered attack scenarios that are mentioned in this study. We compared our approach to an IDS that is based on traditional features, to show the effectiveness of our approach.
With the increase in penetration of photovoltaics (PV) into the power system, the correct prediction of return on investment requires accurate prediction of decrease in power output over time. Degradation rates and corresponding degraded energy estimation must be known in order to predict power delivery accurately. Solar radiation plays a key role in long-term solar energy predictions. A combination of auto-encoder and long short-term memory (AE-LSTM) based deep learning approach is adopted for long-term solar radiation forecasting. First, the auto-encoder (AE) is trained for the feature extraction, and then fine-tuning with long short-term memory (LSTM) is done to get the final prediction. The input data consist of clear sky global horizontal irradiance (GHI) and historical solar radiation. After forecasting the solar radiation for three years, the corresponding degradation rate (DR) influenced energy potentials of an a-Si PV system is estimated. The estimated energy is useful economically for planning and installation of energy systems like microgrids, etc. The method of solar radiation forecasting and DR influenced energy estimation is compared with the traditional methods to show the efficiency of the proposed method.