Department of Electromechanical Engineering

The Department of Electromechanical Engineering is a predecessor of the historical nucleus from which the Faculty of Electrical Engineering Osijek originates, and this is reflected in the fact that activities of this Department are still based upon courses Fundamentals of Electrical Engineering and Electrical Measurements as fundamental courses in the field of electrical engineering.

 

The Department of Electromechanical Engineering is a predecessor of the historical nucleus from which the Faculty of Electrical Engineering Osijek originates, and this is reflected in the fact that activities of this Department are still based upon courses Fundamentals of Electrical Engineering and Electrical Measurements as fundamental courses in the field of electrical engineering, while scientific and professional strength of the Department of Electromechanical Engineering lies in the fields of electric machines and power electronics. The Department consists of two chairs, and it has five laboratories, which resulted from good engineering practice that all courses held within the framework of this Department relate theoretical knowledge to practical work in the laboratory. Scientific research, professional work and expertise are based on the competencies of staff members of the Department of Electromechanical Engineering implying cooperation with the economy through the following activities: 

  • Estimation and identification of power systems and machines from the measurement of characteristic values of the system in time and frequency domain during a transient process;
  • Estimation and identification of characteristics and setting of modern digital excitation systems for large synchronous machines;
  • Characteristics and setting of the power system stabiliser within the synchronous machine excitation system;
  • Setting of digital protection systems in power plants;
  • Testing of all types of small and medium motors and generators;
  • Testing of electric drives in industrial, energy, transport (electric traction) and technological processes;
  • Inspection and testing of wind turbines, gas engines (in biogas plants), compressors;
  • Creating a system for on-line monitoring of power plants and processes to enable continuous monitoring of exploitation conditions, timely identification and fault diagnosis in a plant and plant protection from emergency operating conditions;
  • Monitoring and diagnostics of electric machines in the field of vibration measurement, signal analysis and design of our own solutions for on-line monitoring systems for protection against vibration of rotating machines;
  • Installation, setting and commissioning of various types of frequency converters and starters;
  • Preparing studies of different switching states and harmonic (FFT) analysis of three-phase power transformers;
  • Consulting services in various design projects and modernisation of plants pursuant to prior art and technology, i.e., developing technical solutions; 
  • Services using a mobile measuring system for field testing of high power electric motors;
  • Shooting the range of power supply of induction machines in operation and analysis for diagnostic purposes: bearing failure, broken rotor bars, broken short-circuit rings and interturn short circuits in windings;
  • Preparation of documentation for maintenance, repair and reconstruction of industrial plants;
  • Assembling modern equipment to measure different process variables;
  • Testing of stray losses in transformers and testing of the impact of higher harmonics on transformer operation;
  • Testing of stray losses in induction motors and testing of the impact of higher harmonics on heating, efficiency and total losses of induction motors;
  • Performance testing of induction motors fed by frequency converters and their impact on the power grid;
  • Electromagnetic calculation of induction and synchronous motors for adjusting the magnetic circuit in the design of the same machines;
  • Transformer sizing and testing of transient phenomena; 
  • Determination of reactance and reluctance torque in synchronous machines;
  • Design of controlled elevator drives with induction motors and determining a driving curve, i.e., solving elevator kinematics given the default driving conditions;
  • Modelling and setting of the synchronous generator control structure (turbine control, excitation control - automatic voltage regulator AVR and stabiliser for electromechanical oscillations PSS);
  • Design and testing of propulsion and steering systems of electric vehicles and boats;
  • Design and construction of special electric machines for use in environmentally demanding spaces and in areas with an explosive atmosphere;
  • Design of charging power supply for electric vehicles and vessels from alternative energy sources (water, air);
  • Design and testing of active suspension;
  • Design of uninterruptible power supply  systems;
  • Expertise of non-linear electrical networks;
  • Installing and setting of measuring system parameters for recording and data collection;
  • Problem analysis and mathematical description (modelling) in the field of metrology;
  • Design of virtual measuring devices by using software tools;
  • The choice of transducer components and analysis of power converter operation modes;
  • The choice of a power converter topology with respect to the required type of sources and loads they connect;
  • Record keeping and recording of the harmonic content of selected currents and voltages by means of a waveform analyser (LEM NORMA) and a Tektronix series oscilloscope, and the associated measuring equipment and software (WaveStar);
  • Testing of power converters for use in photovoltaic systems;
  • Design of photovoltaic systems of up to 300 kWp;
  • Numerical calculations of transient and static electromagnetic fields in electrical appliances and devices by using the finite element method;
  • Numerical calculations of transient and static mechanical and thermal stresses of structural elements of electrical devices by using the finite element method;
  • Numerical electromagnetic calculation of induction and synchronous motors for adjusting the magnetic circuit in the design of the same machines;
  • Numerical electromagnetic calculation for transformer sizing and testing of transient phenomena;
  • Numerical calculation of electromagnetic fields of power lines and cables in order to study static and transient conditions, i.e., the determination of parameters; 
  • Optimisation of load distribution and power flows in electric power supply systems by changing the position and the amount of reactive power compensation devices (passive and active);
  • Mathematical modelling of power systems: nonlinear models, linearised models, modal analysis, calculations and analysis of participation factors;
  • Signal analysis, signal processing, interpolation, digital filter processing;
  • Development of new and improvement of existing mathematical models of real physical elements used in various fields of electrical engineering (machinery, power lines, semiconductor devices, etc.) for use in various calculations and simulations;
  • Calculations and simulations of electrical, mechanical and thermal values for complex electrical systems;
  • Posing and solving various optimisation problems in electrical engineering with emphasis on the application in electromechanical and power engineering (e.g., optimal deployment of compensation devices in the electric power system, optimal deployment of distributed generation in the electric power system, optimal maintenance of electric machines, optimal design of electric machines, optimal insulator design, optimal performance of photovoltaic cells, optimal connection of photovoltaic panels to a photovoltaic field, etc.);
  • Parameter estimation of mathematical models of real elements in electrical engineering (e.g., replacement scheme parameters: machines, surge arresters, photovoltaic panels). 

Mission of the Department of Electromechanical Engineering is education and training of future experts in the field of electric machines and drives, as well as management and process automation in industry, power engineering and transport. An equally important aspect is the area of power electronics as the foundation of modern industrialisation in terms of training for the development, engineering design, production management, commissioning and maintenance of modern electrical equipment. The Department consists of two chairs, and it has five laboratories, which resulted from good engineering practice that all courses held within the framework of this Department relate theoretical knowledge to practical work in the laboratory. The vision of the Department of Electromechanical Engineering is based on young professional scientists, whose aim in the coming period is to equip a modern Centre for Electric Machines for the wider region, which, in addition to elementary study and testing of electric machines themselves, entails detailed research in the field of electrical measurements as a basis of electrical engineering, as well as in the field of power electronics as the flywheel in the development of industrial automation, but also new trends in usage of renewable energy sources. The second direction of development is based on current trends in the use of numerical calculations in modelling electromechanical devices based on theoretical electrical engineering the aim of which is to form a scientific research team, or to establish a laboratory for numerical calculations in electrical engineering. In the forthcoming period, the development shall be based on several directions: 

1. Establishment of a modern Centre for Electric Machines as a scientific research centre of excellence within the framework of which the following laboratories shall be affirmed:

Electric Machines Laboratory
• Electric Drives Laboratory
Laboratory for Electric Circuits Analysis and Metrology
Power Electronics Laboratory
• Laboratory for Testing Electric Vehicles and Vessels

2. Establishment of the Photovoltaic Power Systems Laboratory as a component of the future Centre for Renewable Energy Sources under the leadership of the Department of Power Engineering. The main task of this Laboratory is to develop procedures for exploring power converters typical of photovoltaic systems.

​3. Establishment of the Numerical Calculation Laboratory as a component of the future Centre for Numerical Calculations in Electrical Engineering, which would be developed parallely by the Department of Communications, the Department of Power Engineering and the Department of Computer Engineering and Automation. Modern trends in the use of numerical calculations in modelling electromechanical devices today are an indispensable part of the process of designing, planning and analysis, and they are based on the fundamental laws of electrical and magnetic fields, Maxwell’s equations and boundary conditions. 

4. Principles of the research strategy aim at creating preconditions for linking scientific research and professional work, which would enable employees of the Department of Electromechanical Engineering to participate in professional projects and expertise. In so doing, the funds necessary for the purchase of equipment for the creation of conditions for research, testing and measurements shall be provided first through scientific projects from pre-accession funds and later on from the Cohesion and Structural Funds. Hence, it is necessary to increase the number of applications for EU research projects in order to reinforce the publication of research results in international scientific journals with the impact factor. It is also necessary to intensify connections with universities in the EU and the immediate region, as well as to apply for joint projects, which also implies greater mobility of scientists of the Department of Electromechanical Engineering. Currently, employees of the Department of Electromechanical Engineering have successful communication with scientists from the immediate region, i.e., Zagreb, Split, Maribor, Budapest, Novi Sad, Tuzla, and Sarajevo, as well as with scientists from Spain, Greece and Ukraine.