Faculty of Mechanical Engineering
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Item type:Publication, A Review of Modeling Approaches and Key Parameters in the Simulation of Wastewater Treatment Plants(MDPI AG, 2026-01-20); ; ; ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Simulacija i odstranjivanje stick-slip efekta servosistema sprovodnog aparata hidraulične turbine(University Library in Kragujevac, 2021-01); ; ; ; Friction is a repeatable and undesirable problem in hydraulic systems where always has to be a tendency for its removal. In this paper, the friction model is presented through which the most accurate results are achieved and the way of friction compensation, approached trough technique presented with the mathematical model of a hydraulic cylinder of a hydro turbine wicket gate controlled by a servomechanism. Mathematical modelling of a servo mechanism and hydraulic actuator, and also the simulation of hydraulic cylinder as a part of a hydro turbine wicket gate hydraulic system where the stick-slip phenomenon is present between the system components that are in contact is presented. Applied results in this paper and the theory behind them precisely demonstrate under what circumstances the stick-slip phenomenon appears in such a system. The stick-slip effect is simulated using Simulink and Hopsan software and the analysis of the results are given in this paper. Removal of the stick-slip effect is presented with the design of a cascade control implemented to control the behaviour of the system and remove the appearance of a jerking motion. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Energy flexibility scenarios for North Macedonia(International Association for Hydro-Environment Engineering and Research (IAHR), 2022); ; ; The Paris Agreement signed in 2015, unites nearly 200 countries on the goal of limiting global warming and lowering carbon emissions. The goal of lowering carbon emissions can mainly be achieved by lowering fossil fuels within the energy sector since their use in electricity generation is a significant contributor to greenhouse gas emissions. This is why European countries, as well as North Macedonia, are planning to reduce the amount of climate-damaging fossil-fueled power plants, but to cover electricity demand, the share of renewable energies (in North Macedonia mostly wind and solar energy, here addressed as intermittent renewable energy sources - IRES) within their power systems must be increased. Changing power systems and including higher shares of IRES will increase imbalances and thus the need for flexibility (refers to means able to balance electricity supply and demand). Imbalances have always occurred in power systems, resulting from various reasons, and power systems are able to react with flexibility. Considered options, categorized into four kinds of flexibility (dispatchable generation, demand side management, increased interconnection, and energy storage), all offer possibilities to balance the systems by different approaches. Although all providing individual advantages, hydropower, especially pumped storage hydropower, was identified in this paper to be a very flexible, diverse option and a technology capable of meeting flexibility challenges set by the increase of IRES. The need for flexibility in the hydropower production could be improved using variable-speed turbines instead of multiple start-stops depending on the grid demand. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, 14. Energy Flexibility Scenarios for North Macedonia(IAHR, 2022-06-22); ; ; The Paris Agreement signed in 2015, unites nearly 200 countries on the goal of limiting global warming and lowering carbon emissions. The goal of lowering carbon emissions can mainly be achieved by lowering fossil fuels within the energy sector since their use in electricity generation is a significant contributor to greenhouse gas emissions. This is why European countries, as well as North Macedonia, are planning to reduce the amount of climate-damaging fossil-fueled power plants, but to cover electricity demand, the share of renewable energies (in North Macedonia mostly wind and solar energy, here addressed as intermittent renewable energy sources - IRES) within their power systems must be increased. Changing power systems and including higher shares of IRES will increase imbalances and thus the need for flexibility (refers to means able to balance electricity supply and demand). Imbalances have always occurred in power systems, resulting from various reasons, and power systems are able to react with flexibility. Considered options, categorized into four kinds of flexibility (dispatchable generation, demand side management, increased interconnection, and energy storage), all offer possibilities to balance the systems by different approaches. Although all providing individual advantages, hydropower, especially pumped storage hydropower, was identified in this paper to be a very flexible, diverse option and a technology capable of meeting flexibility challenges set by the increase of IRES. The need for flexibility in the hydropower production could be improved using variable-speed turbines instead of multiple start-stops depending on the grid demand. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Identification of the Conduit Water Starting Time Constant in Hydropower Plants Using LSTM and MLP Machine Learning Algorithms(Acadlore Publishing Services Limited, 2025-03-31); ; The accurate determination of the conduit water starting time constant ( ) is critical for optimizing hydro turbine performance and dynamic control in hydropower plants. Instead of relying on conventional calculation methods, machine learning (ML) techniques, specifically long short-term memory (LSTM) networks and multilayer perceptron (MLP) models, have been employed to identify . The dataset used for model training and validation comprises real operational data collected from two hydropower plants. The effectiveness of both algorithms in identification has been evaluated through simulation, with Python serving as the primary programming environment. The findings indicate that, despite its more complex architecture, LSTM does not necessarily yield superior results. In contrast, MLP, as a relatively simpler model, demonstrates greater accuracy in estimating , suggesting that intricate network structures are not always required for precise identification. Additionally, an optimization function ( ) has been utilized to assess the reliability of the identified values by comparing them with actual hydro turbine responses. The results underscore the practicality of MLP in hydropower system modeling, providing a computationally efficient alternative for conduit water starting time constant identification. These insights contribute to improving real-time turbine control and enhancing the efficiency of hydropower generation. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Design of Hydropower Plant PID Controller Parameters Using Artificial Neural Networks(IEEE, 2024-05-15); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, New Approach in Hydropower Plant Control Based on Neural Networks(University Library in Kragujevac, 2022); ; ; ; <jats:p>A new approach to efficient, faster, and intelligent hydropower plant (HPP) control, where constituent equipment is described with highly non-linear mathematical models based on the recommendation from the working group of IEEE on prime movers, is represented in this paper. HPP stability and high efficiency are important factors dependent on the dynamic changes in the energy system demands and the starting time of the plant because the obtained energy is very flexible to those changes in the energy system. This paper is shown and analysed the implementation of the artificial neural network-based controller with PID as an auxiliary controller which helped achieve better behaviour, faster plant stabilization, and operation. The benefits of new technologies and possibilities led to improvements in HPP control and faster system operation. This is achieved by using MATLAB® – Deep Learning Toolbox whereas the simulations are prepared in Simulink. Artificial Neural Networks (ANN) as a technique used in the HPP control systems have advantages in getting a stable and faster response but the complexity of the structure behind the neural networks (NN), meaning algorithms, number of hidden layers, training function, activation function can complicate and destabilize the process. In this paper, the focus is put on the mechanical power responses improvement and the advantages of implementing new technologies contrary to the problems that can occur by using them such as plant destabilization by implementing minor changes, fitting parameters, learning, and training processes, number of hidden layers/neurons, number of epochs, etc.</jats:p> - Some of the metrics are blocked by yourconsent settings
Item type:Publication, IoT System for Real-Time Water Quality Measurement and Data Visualization(IEEE, 2023-06-06); ; ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Computational Methods For Water Quality Index Calculation Using Real-Time Measurement System(IEEE, 2024-06-11); ; ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Development and Hardware-in-the-Loop Simulation of an Air Purifier Automatic Control System(IEEE, 2021-06-07); ; ; Rath, Gerhard