Power Lab Banja Luka

About the lab

The members of the Laboratory for Electrical Power Engineering at the Faculty of Electrical Engineering, University of Banja Luka are engaged in research and projects related to all aspects of electrical power engineering.
The main area of research is enhancement of reliability indices in medium voltage distribution networks by employing fault passage indicators.

Featured research (14)

Standalone hybrid systems based on renewable energy sources may represent a convenient and cost effective option for powering isolated consumers located far from the existing grid. In this study the focus is on particular photovoltaic-wind-diesel-battery systems which supply mobile telephony base stations. In the study, both the consumption of telecommunication electronic equipment and the consumption of cooling devices are taken into account. Nine characteristic locations across Europe with different climatic conditions were selected for comparative techno-economic assessment. For each location, a comprehensive simulation and optimization routine was performed, in order to find the optimal system configuration and the minimum amount of total annualized costs. The obtained results are discussed and some conclusions regarding system sizing at different locations are drawn.
In contemporary electrical power systems real-time power line monitoring and supervision are commonly performed using simple non-invasive devices with contactless magnetic field measurement. Measured magnetic fields are commonly employed for fault detection in fault passage indicators, but they can also be used to determine electrical and non-electrical power line variables. In this paper a novel adaptive method for conductor sag estimation is proposed, using magnetic field measurement. The method is based on the properly calibrated approximate power line magnetic field model, in which catenary-shaped conductors are modeled by tilted straight-line conductors of infinite length. By this approximation, the overhead power line model can be used in simple devices for power line monitoring in real-time. Applicability and accuracy of the proposed method for power line conductor sag estimation is verified by computer simulations and measurements on a three-phase overhead line model, scaled to laboratory conditions.
The paper proposes a novel planning approach for optimal sizing of standalone photovoltaic-wind-diesel-battery power supply for mobile telephony base stations. The approach is based on integration of a comprehensive probabilistic sequential Monte Carlo simulator and a black-box optimizer using DIRECT (DIviding RECTangles) method. The main property of the simulator is that input variables are modeled as correlated random processes rather than independent random variables without a time index. By taking into account autocorrelation and mutual correlation, temporal properties of all input variables are kept realistic, such as sunrise and sunset times in irradiance model, daily and seasonal changes in temperature model, and consumption of cooling devices and electronic equipment which depends on the ambient temperature and setting of the parameters of the control devices. The optimization target is to select rated capacities of major system components and to tune the main control parameters for achieving minimum total annual costs without compromising system reliability. The proposed algorithm is tested on planning a typical 2 kW potential base station located on a windy and sunny hill in the Mediterranean region.
This paper presents a laboratory setup for testing and experimental verification of fault detection methods based on contactless measurement of power line magnetic field. The setup consists of a physical power line model scaled to laboratory conditions with two orthogonal measuring coils installed on one support pole underneath phase conductors. Voltages induced in the coils are amplified and filtered out by using analog electrical circuits and are fed to a digital data acquisition board. The sampled voltages are digitally processed by employing a generalized fault detection method previously developed by the authors. In this paper the main steps for designing the measuring coils, analog amplifying and filtering circuits are described in detail. The developed laboratory setup is verified by experiments for different shunt and series faults.
Optimal sizing of standalone hybrid renewable power supply for mobile telephony base stations is considered in this paper. This task is very complex due to stochastic nature of input variables such as wind speed, solar irradiance, ambient temperature and electric load. Further concern is modeling of the power consumed by cooling devices which is also uncertain variable dependent both on ambient conditions and power dissipation of telecommunication equipment. The realistic behavior of the station both in electrical and thermal terms can be analyzed only by a comprehensive probabilistic simulator. The basic idea of this paper is to systematically vary the main input parameters (rated powers of wind turbine and photovoltaic system along with battery capacity) and to run a Monte Carlo simulation for each considered variant observing the technical and economic indicators. Based on the minimum annual costs, it is possible to choose the best available investment solution. Simple optimization can be extended to multi-objective by adding some additional goals, such as minimizing the operating time of a diesel backup generator. The optimization method is tested on an illustrative example of a base station located in the Mediterranean area.

Lab head

P. Matic
  • Faculty of Electrical Engineering
About P. Matic
  • P. Matic currently works at the Faculty of Electrical Engineering, University of Banja Luka. P. does research in Industrial Engineering, Engineering Education and Electrical Engineering. Their most recent publication is 'Non – Regenerative IPMSM Drive Braking Scheme Based on q – Axis Current Component Limiting'.

Members (5)

Cedomir Zeljkovic
  • University of Banja Luka
Đorđe Lekić
  • University of Banja Luka
Predrag Mršić
  • University of Banja Luka
Bojan Erceg
  • University of Banja Luka
Nemanja Kitić
  • University of Banja Luka, Faculty of Electrical Engineering