Viliam Fedak

Survey of distance laboratories in power electronics

The paper presents an overview of the current state of development of distance and virtual laboratories in Electrical Engineering with a special attention to the fields of Power Electronics and Electrical Drives. Based on a broad overview of the open Internet resources from fields of Electrical Drives and Power Electronics and taking into consideration the ideas presented recently at conferences and published in journals and own experiences, the challenges and ways of future development of e-learning in the presented fields are sketched. This survey brings an overview of the contents of real experiments of the remote controlled laboratories that are placed at various universities. A special care is devoted to preparation of the learners to experimentation, including examining their knowledge before joining to the experiment. In the Appendix a complete survey of distance laboratories is given.

Modeling and simulation of the BLDC motor in MATLAB GUI

The paper proposes a model of brushless DC motor considering behavior of the motor during commutation. The torque characteristic of BLDC motor presents a very important factor in design of the BLDC motor drive system, so it is necessary to predict the precise value of torque, which is determined by the waveforms of back-EMF. After development of simple mathematical model of the BLDC motor with sinusoidal and trapezoidal waveforms of back-EMF the motor is simulated in the MATLAB/Simulink environment. Based on analysis of the time responses a comparison study of results of both BLDC motor types is presented in Graphical User Interface of MATLAB environment.

PEMCWebLab - Distance and virtual laboratories in electrical engineering: Development and trends

The paper deals with basic philosophy and structure of remote controlled laboratory for experimentation in electrical engineering. The laboratory collects experiments from fields of power electronics, electrical machines, electro-mechanical and motion control systems. The workbenches in the real laboratory are used over Internet. The real experiments of the remote controlled laboratory are placed at various universities. A special care is devoted to preparation of the learners to experimentation, including examining their knowledge before joining to the experiment. To have a feeling of participation in the experiment, except of the measurement data, also the signal from Web camera is transferred to a distance operator.

Dynamic Simulation of Electrical Machines and Drive Systems Using MATLAB GUI

Since the first appearance, the fields of electrical machine and drive systems have been continuously enriched by introduction of many important topics. Progress in power electronics, microcontrollers, new materials and advances in numerical modeling have led to development of new types of electrical machines and in field of electrical drives to realization of complex control algorithms. Their verification is usually done by simulation during system design, thus the effort is concentrated to development of simulation models.

Dynamic Emulation of Mechanical Loads with Backlash Based on Rapid Control Prototyping

The paper discusses advanced control of a dynamometer performing dynamic emulation of mechanical loads. Assumed is certain class of nonlinear load with backlash. Paper presents and describes the basic control structure, which can be used for validation of speed algorithms and its practical implementation with rapid control prototyping. Validation of experimental results against the simulations has been performed with experimental test bench containing permanent magnet DC machines and DC-DC converters with high sampling times in current control loops.

Non isolated and non-invertingCockcroft-Walton multiplier based hybrid 2Nx interleaved boost converterfor renewable energy applications

In this paper hybrid non isolated and non-invertingCockcroft-Walton multiplier based 2Nx InterleavedBoost converter (2Nx IBC) for renewable energy applications is presented. The presented hybrid boost converter topology is derived from non-inverting Nx Multilevel Boost Converter (Nx MBC) and inverting Nx Multilevel Boost Converter (Nx MBC). In renewable energy applications, generated voltage needs to be stepped up with high conversion ratio using a DC-DC converter at voltage levels as per the application requirement. The advantages of the presentedtopology of interleaved converter are high voltage conversion ratio, reduce ripple, low voltage stress, non-inverting output voltage without utilizing the high duty cycle, coupled inductors and transformer. The main advantage of presented topology consists in increasing voltage gain by adding capacitor and diode into circuitry without disturbing the main circuit. Moreover, the presented topologyis compared with several recent non isolated high gain DC-DC converters. The proposed topology is simulated in MATLAB/SIMULATION andobtained results verify the validity of the design and operation of converter.

Educational visualization for teaching power electronics

Different methods of visualization and graphic representation of converter operation are surveyed and possible ways of interactive animation are introduced. Effectiveness of selected e-learning method is demonstrated on example of an converter commutation, which is explained first with traditional method and for comparison with interactive animation (e-learning). I. INTRODUCTION Present engineering has to deal with increasingly complex systems. In particular, this is the case in electrical engineering. Though this is obvious in microelectronics, also in the field of power systems engineers have to design, operate and maintain highly complex systems such as power grids, energy converters and electrical drives. This is reflected in engineering education, where teachers try to communicate the many aspects of complex systems and where students try to learn and deal with this complexity. The introduction of new technologies (e.g. ICT) in teaching, though very promising at first glance may turn out to be counterproductive when the accent is on teaching, rather than learning. The same technologies may prove to be highly effective, if they are introduced to support the understanding and, consequently, handling and even designing of complex systems.

Philosophy of Interactive e-Learning for Power Electronics and Electrical Drives: a Way from Ideas to Realization

The paper reports about methodology at design of interactive e-learning modules that are suitable both for teaching and learning. They cover special topics of electrical engineering, starting from the fundamentals, through electrical machines, power electronics to the fields of controlled electromechanical energy conversion, like electrical drives, complex drive systems, application of drives, mechatronic systems, telemanipulation, and robotics. In the paper, the emphasis is devoted in detail to philosophy and realization of the modules from fields of Power Electronics and Electrical Drives. On several examples there are explained main principles and specialties at their development.

Wavelet transform with fuzzy tuning based indirect field oriented speed control of three-phase induction motor drive

This manuscript presents the details about the novel controller using wavelet transform and fuzzy logic tuning for speed control of an induction motor drive. The conventional proportional-integral (PI) speed controller in an indirect vector control of induction motor drive has been replaced by the proposed controller for an improved transient and steady state performances. The discrete wavelet transform has been used to decompose the error speed into different frequency components and the fuzzy logic is used to generate the scaling gains of the wavelet controller. The complete model of the proposed controller along with an induction motor drive incorporating the proposed controller has been developed in numerical simulation software using Matlab/Simulink environment and a set of results are provided within this paper in comparison to the conventional controller scheme.

Teaching Electrical Drives and Power Electronics: eLearning and Beyond

Today the education is influenced by eLearning facilities and the accent lies in skills and (deep) understanding rather than in knowledge. In the paper survey of the present state of development of eLearning in Electrical Drives and Power Electronics (ED&PE) is given. Problem based and project based education are the keywords for modern education. This gives to the student a very good knowledge in individual disciplines while integrating the disciplines together to a useful whole of knowledge and skills is difficult. Integrating the disciplines and finding new challenging examples and teaching methods is illustrated on example of an electrical drive for a hybrid car. The paper summarizes the results achieved in the development of multimedia based eLearning tools in the field of electrical drives and power electronics as well as distance and virtual laboratories. Finally many challenges for future development of the eLearning are listed