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The idea of the paper is to present a successful symbiosis of the products of the leading firms in the electronics - National Instruments and Texas Instruments. The developed test bench is composed of hardware for data acquisition and control (sbRIO), working with the LabVIEW environment and the novel Power Management Lab Kit (PMLK) educational boards. The manipulation of these hi-tech boards becomes more accessible for a broader range of students, including undergraduates in schools, with the use of LabVIEW virtual instruments (VI), which assist the trainees in the manipulation of the kits - for example if a incompatible working configuration is set, the VI will pop up a message describing the result if its execution. Moreover it will provide guidance for choosing the right setup along the active decisions from the student and also with the VI can be taken measurements, without the need of external hardware. [ABSTRACT FROM AUTHOR]

The aim of the paper is to create a polymorphic informational model of a ZVS Buck quasi-resonant DC-DC converter for the modeling purposes of the object. For the creation of the model is applied flexible open standards for setting, storing, publishing and exchange of data in distributed information environment. The created model is useful for creation of many and different by type variants with different configuration of the composing elements and different inner model of the examined object. [ABSTRACT FROM AUTHOR]

Guaranteeng the parameters in the output of the power electronics device is of great importance for achieving the desired quality of the process of energy conversion. The combined methods for realization of the electronic devices with guaranteed parameters requires the usage of systematic approach in the realization of the power electronics device - from the stage of the parameter formulation to the receiving of the end product. In the investigation the application of the modelling and software products for the research are growing more and more. In that relation it is necessary the creation of a common programming environment in which the diversity of application programs can operate. In the paper is present an automated synthesis and design of single-transistor dc-dc converters. [ABSTRACT FROM AUTHOR]

The aim of the paper is to create a polymorphic informational model of a ZVS Buck quasi-resonant DC-DC converter for the modeling purposes of the object. For the creation of the model is applied flexible open standards for setting, storing, publishing and exchange of data in distributed information environment. The created model is useful for creation of many and different by type variants with different configuration of the composing elements and different inner model of the examined object. [ABSTRACT FROM AUTHOR]

Guaranteeng the parameters in the output of the power electronics device is of great importance for achieving the desired quality of the process of energy conversion. The combined methods for realization of the electronic devices with guaranteed parameters requires the usage of systematic approach in the realization of the power electronics device - from the stage of the parameter formulation to the receiving of the end product. In the investigation the application of the modelling and software products for the research are growing more and more. In that relation it is necessary the creation of a common programming environment in which the diversity of application programs can operate. In the paper is present an automated synthesis and design of single-transistor dc-dc converters. [ABSTRACT FROM AUTHOR]

In the paper work a experimental study has been made with practical trend, of a Buck DC - DC quasi resonant converter, working with ZVS (Zero Voltage Switching). In the work a mathematical expressions, for the parameters, which describe the work of the power part of the circuit, has been made. With their help a method for designing of a Buck ZVS DC - DC quasi resonant converter has been proposed. The advantage of this method is the use of simple expressions, which facilitate the designing, but in the same time an acceptable error of 10 % is kept, commensurate with the tolerance of the values of the reactive elements (capacitor and inductor). The verification of these expressions has been made with modeling (Matlab/Simulink), computer simulations (LTSpice) and experimental measurements on a laboratory stand. [ABSTRACT FROM AUTHOR]

The paper discusses the electronic control of Induction heater power converter for ferromagnetic materials melting working in independent excitation. The system of power electronic converters is composed by a controlled three-phase rectifier and parallel current source inverter. Analysis of regime with fixed current from the DC supply source has been made. This guarantees working with maximum power and respectively short meting process time. [ABSTRACT FROM AUTHOR]

Logisim is a program used for digital circuits simulation - gates, flip-flops and latches. This paper presents a simple method, which allows simulation of circuits, designed for the power electronics devices, based on digital control units. [ABSTRACT FROM AUTHOR]

In the work photovoltaic systems with DC load are studied. The study was conducted in order to increase effectiveness of photovoltaic systems. [ABSTRACT FROM AUTHOR]

The paper presents comparison between resonant inverters with reverse diodes and resonant inverters with limited voltage over the commutating elements (capacitors and inductances). Output and input characteristics of these inverters are given. [ABSTRACT FROM AUTHOR]

The paper presents a 2D model of a system for contactless inductive energy transmission. Graphical dependences for the inductance of the transmission coil on the frequency, on the magnetic permeability of the concentrators and on the distance between the coils are obtained. In addition, results for the power of the transmitting coil and the dependence of the induced voltage in the receiving coil on the frequency of the power supply are shown. An analytical model of an air transformer is used to explain the numerical results. [ABSTRACT FROM AUTHOR]

This paper aims to present an approach which automates electronic circuit design. It is based on index matrices with real number elements and their software implementation. Both they are developed by the authors as an example of universal tool on a wide class of electrical devices, and this approach is performed for complex components which have more than two terminals (functioning of PID-regulators is implemented). Designed programming classes are used in a.NET application in order to handle electronic circuits, and simulation on power converters functioning is presented. [ABSTRACT FROM AUTHOR]

In the current paper a model of bidirectional DC/DC multi quadrant converter is developed. The proposed model is composed by a separately excited DC motor, a buck-boost converter and a proportional-integral (PI) regulator. The solution is described with the aid of system of differentials equations and realized in the visual environment MATLAB/Simulink. Two operation modes are studied: acceleration mode and braking (regenerative) mode. From the presented and discussed results it is observed that the proposed solution is suitable for hybrid electric vehicles applications with multiple energy source such as battery and supercapacitor. [ABSTRACT FROM AUTHOR]

In the current paper a generalized mathematical model for control of energy flows in electric and hybrid vehicles is proposed. This solution includes an electric motor and internal combustion engine with their control. The main objective of this study is to estimate the optimal distribution of energy between several supplying sources. The used methodology is described with mathematical equations. The proposed model is realized in the environment MATLAB/Simulink. The generalized model allow better control and optimization of the entire system during acceleration and regenerative braking processes. [ABSTRACT FROM AUTHOR]

In the work are presented basic resonance circuits, which are used in resonance energy converters. The following resonant circuits are considered: serial, serial with parallel load parallel capacitor, parallel and parallel with serial loaded inductance. For the circuits under consideration, expressions are generated for the frequencies of own oscillations and for the equivalence of the active power emitted in the load. Mathematical expressions are graphically constructed and verified using computer simulations. The results obtained are used in the model based design of resonant energy converters with DC or AC output. This guaranteed the output indicators of power electronic devices. [ABSTRACT FROM AUTHOR]

This paper presents a study on the possibilities for implementation of local heating, air-conditioning and electricity generation (trigeneration) as distributed energy resource in the Smart Grid. By the means of microturbine-based generators and absorption chillers buildings are able to meet partially or entirely their electrical load curve or even supply power to the grid by following their heating and air-conditioning daily schedule. The principles of small-scale cooling, heating and power generation systems are presented at first, then the thermal calculations of an example building are performed: the heat losses due to thermal conductivity and the estimated daily heating and air-conditioning load curves. By considering daily power consumption curves and weather data for several winter and summer days, the heating/airconditioning schedule is estimated and the available electrical energy from a microturbine-based cogeneration system is estimated. Simulation results confirm the potential of using cogeneration and trigeneration systems for local distributed electricity generation and grid support in the daily peaks of power consumption. [ABSTRACT FROM AUTHOR]

In the following article a converter, providing management of the energy flow from the photovoltaic system (PV) to the elements for energy storage - supercapacitors, has been studied. The proposed converter provides charging and voltage balancing across series connected elements (supercapacitor cells). Simulation and experimental studies of the proposed circuit, from the PV system, has been made. Characteristics of the tested converter were made. [ABSTRACT FROM AUTHOR]

The purpose of this paperwork is to present a developed an experimental stand for testing different kinds of bi - directional circuits, providing a work of a supercapacitors in renewable energy systems - photovoltaic systems. A simulation model has been created of the studied bi - directional converter. During combined operation between a supercapacitor and a battery there are mainly two kinds of wiring methods. In the first method the battery is working in buffer mode and the supercapacitor is connected to the bi - directional converter. The second method is when the supercapacitor is working in buffer mode and the battery is connected to the bi - directional converter [1, 5]. In this paperwork a renewable energy system build in the first method is studied. For testing different circuit kinds of bi - directional converters in photovoltaic systems, an experimental stand, described in this work, has been created. The information measuring system is realized by the softwer LabView. In the document a comparison between the simulation and experimental results has been made. [ABSTRACT FROM AUTHOR]

In this article is proposed a method for forecasting vehicle traffic intensity in urban conditions and provides an estimate of the forecasting error. For input data in this study are used: the number of vehicles that have passed through a location of the road, based on data collected by observations; meteorological conditions; the day of the week; the season. For this purpose, database processing methods, statistical and stochastic methods are used. [ABSTRACT FROM AUTHOR]

Forecasting is a special scientific study, the subject of which is the perspective for the development of the phenomenon. It is of great importance for many scientific and applied fields. This article presents a stochastic model for microgrid load forecasting. Statistical and stochastic methods are used for forecasting. [ABSTRACT FROM AUTHOR]

In this article, a stochastic model for prediction of microgrid photovoltaic power generation, using statistical and stochastic methods is presented. The study is performed in the following steps: Processing of a large database of historical data (Data Mining); Construction of a stochastic forecasting model; Reporting a symmetric mean absolute percentage error in forecasting. [ABSTRACT FROM AUTHOR]

The paper presents the creation of a general mathematical model of a two-step optimization problem which finds the most energy efficient route where the battery and the electric engine of an electric-bicycle are used to minimum. In the first step, a multi-criteria problem is solved which finds the most efficient mode of operation of the battery and the engine in every segment part of the complete route. To solve this task a scalarization method is used (also known as weighted sum method). In the second step, a common most efficient route is found by applying a network optimization model. To find the solution a method of dynamic optimization is used - Bellman's Principle. The major part of the paper is dedicated to the mathematical models, the approaches and the demonstration of the models’ workability. For this reason, the generation of data is based on the a priori known information as well as on information which is periodic and stochastic in the time and space. [ABSTRACT FROM AUTHOR]

The paper presents the creation of a general mathematical model of a two-step optimization problem which finds the most-safer route of an electric-bicycle cyclist. The first step is a multi-criteria problem which finds the average risk in the different segments which forms the complete route. To solve the problem, a scalarization method is used (also known as weighted sum method). In the second step, the safer route is found by applying a network optimization model. To find the solution a method for dynamic optimization is applied (Bellman's Principle). The generation of data is based on the a priori known information as well as on information which is periodic and stochastic in the time and space. [ABSTRACT FROM AUTHOR]