This paper deals with heatsink design and verification of IGBT-based full-bridge converter of rated power 150 kVA. The converter is designed for air cooling-based installation of total power 1.35 MVA operating in medium-voltage power system. In order to exactly determine the cooling abi...

This paper proposes new zero current switching (ZCS) transformerless high gain DC-DC converters for renewable energy conversion systems. A conventional high gain transformerless DC-DC converters derived with a simple auxiliary resonant network to obtain zero current switching (ZCS) turn-off condition&...

In this article we tackle the main problem of nanoparticles which is aglomeration, sedimentation and their long term stability. It has been proved that the nanoparticles offer various benefits for improving the electrical parameters (like breakdown voltage, dissipation factor tan,etc.) of in...

A Simulink/DriveSize based model for the hybrid speed and throttle control of a centrifugal pumping plant equipped with a variable speed drive is proposed in this paper. The model provides the possibility of input power estimation for mutual throttling and speed control. In ad...

The paper introduces basic characteristics of the traction drive and the way how modern multi-system traction vehicle can be realized. The main aim of the paper is focused on using single phase matrix converter (1ph MC) as an input converter for medium frequency transformer. T...

This paper deals with the verification of the maximum current rating of MOSFET transistors in a discrete package TO-247AC. The main motivation for this analysis was the redesign of AC power drive chain for electric go kart with three phase power converter of the output no...

Static Var Compensators (SVC) are related to improve quality of electrical energy in power grids. There are described two topologies of the static var compensator in the paper. First of them is a star/Y-connected topology and the second one is a delta/D-connected topology....

Key design and operation parameters of the system for magnetically guided actuation of miniature robots on planar surfaces are analyzed and discussed. The study is carried out on the numerical analysis and also on the experimental measurement on the prototype of the system. Special...

This paper presents a new approach to the design of direct digital frequency synthesizer (DDS) with possibility of fractional frequency tuning. Such DDS has advantage if small number of bits for phase accumulator is used. A new DDS frequency synthesizer was designed to enable ...

Cardiac output (CO) and stroke volume (SV) are important hemodynamic parameters for evaluation of cardiovascular performance of the subject. Especially noninvasive estimation of CO during sub maximal and maximal work is valuable. In this paper, one method suitable for athlete CO estimation&#...

In this paper the experiments with two or more mutually coupled phase locked loops (PLL) are described. The different types of coupled PLLs are simulated and results are confirmed by measuring in real systems. The experiments include analog and digital PLLs and simulation. In ...

Finite control set model predictive control (FCS-MPC) is one of successful model predictive control approaches in electric drives which offers effective solution to multi variable multi criteria problems. The optimal control is found by “brute force” search over the limited set of possi...

Finite control set MPC of IM drive is known to produce a spread spectrum of the stator currents. Spectrum of the acoustic noise also exhibits higher spread than that of the PWM which may be perceived as more pleasant sound by humans. Predictive acoustic noise control ...

Design of electrical machines with low carbon footprint is an actual topic in the industry. Total cost of ownership is the standardized methodology to consider the lifetime costs of a power transformer already in the pre-concept design stage. There still does not exist a widel...

The topic of the article is new insights into the load of transformers depending on their own losses. Transformers are among the most common, but important elements of the transmission and distribution networks. This is a reliable device with a guaranteed lifetime at the level...

This paper is focused on modeling of existing cogeneration power plant with backpressure turbine in Pilsen. The first motivation of the modeling is better understanding of all cycle features and its limitations. The second motivation is further investigation of some innovative implementation...

Standard short circuit tests of HV SF6 circuit breakers need high power sources and special synthetic facilities. Tests consist of many standard disciplines. Each of short fault disciplines requires high parameters from high power sources. They also require exact measurement and accurately&#...

Operational direct current grids (ODCG) are one of the most important components of many power plants and substations, for example, hydroelectric power plants. They are designed for power supply of relay protection devices, signalization and automation, and for the power supply of impor...

Accurate temperature control is an important part of an induction brazing process, because of a small difference between melting points of aluminum and soldering material. However, direct measurement of the local temperature at the spot of brazing is not possible in a production li...

In this article, we investigate the periodic nonlinear second order ordinary differential equation with damping u''(x) + r (x) u'(x) + g(x, u(x)) = f (x) , x ∈ [0, 2π] , u(0) = u(2π) , u'(0) = u'(2π) , where g is a L1-Caratheodory function, r ...