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The location of distributed generators (DG) with different size on the power distribution systems could modify the voltage profile and impacts the level of real power losses. Faster optimization technique as well as a high computational speed of load flow are therefore required. This paper presents a linear model and an algorithm that allow to calculate the real power losses of the system. This methodology...
This paper presents the modelling and simulation of a low-power Brushless DC machine in a Rotor Flux Oriented mode in MATLAB/Simulink. The modelling of the machine is presented in the synchronous dq frame. Using this model suitable Proportional Integral controllers have been designed for the Rotor Flux Oriented speed and current loops. Sensorless simulation estimates obtained from a back-emf observer...
In this paper, we propose a method for identifying the differential mode impedance of a paralleled converter cell. The equivalent Thevenin / Norton circuit method is used for prediction. The predict of ElectroMagnetic Interference (generated by converters connected to the electrical network to identify the sources of noise, impedance and harmonics according to the identification of the contribution...
Individual pitch control is seen as a promising control technique for load reduction of the rotor blades in megawatt wind turbines. As the rotor blades are getting bigger and bigger, the asymmetric loads due to wind speed variations across the rotor area are increasing, too. Modern wind turbines include individual pitch actuators for every blade and the control effort is also reasonable. This is why...
To maximise essential system performance parameters, this research combines electrical, mechanical and position control models of a high-precision mechatronic system. The degradation of system performance induced by identified amplifier errors is analysed to reveal the significance of each error mechanism. The simplified outline of a mechatronic system is given to which models of the power amplifier...
This paper describes a methodology to build a combined conducted and radiated emission model for integrated circuits. The development of emission models of a FPGA extracted from two different approaches is presented and discussed. The first approach allows to build a predictable model from FPGA implementation and some passive measurement on FPGA device. The second approach allows to build a model...
The power electronic based Grid Side Converter (GSC) is the key technology for interconnecting RES. In order to obtain accurate simulation results, it is important to have a detailed-realistic modelling of GSCs. This requires a very small solver step (i.e., solver period near 1 μs) due to the high-frequency switching operation of these converters. Such a small solver period imposes computational constraints,...
Local grids featuring multiple carriers (electricity, gas and district heating) have attracted a certain degree of attention in the last few years, since technologies and components for the efficient conversion and storage of energy in different forms are becoming increasingly available. Grids of this type interact through energy hubs, i.e. grid nodes featuring connections to multiple energy carriers...
In present work is carried out modelling of single transistor parallel ZVS DC-DC converter. Main advantage of power circuit is direct work in steady mode. Thus, that allows avoiding a starting procedure and guarantees reliable operation in significant major change in load occur. The model is realised with Matlab. Computer simulations and experiments in lab model are performed by which the model is...
In the following paperwork a photovoltaic power supplying system for telecommunication equipment has been modelled. The power supplied equipment can be radio communication equipment, active equipment for optic networks and other. The model is developed in LabView. The chosen capacities of the energy storage elements (ESE) can be determined by using the developed model. The model can be used to determine...
The study focuses on the investigation small-signal stability in power systems using two methods. One of the methods is traditional method of modal analysis investigating behavior of the eigenvalues. Another one is a new sub-Gramians method that was worked out in Institute of Control Sciences (ICS) RAS. The method is based on the application of the so-called sub-Gramians derivable from solving the...
Variable frequency drives are widely used in industrial enterprises and are therefore an influential part of electric load. The aim of this study was to define a relation between voltage unbalance and variable frequency drive power. The mathematical models of drives with a cycloconverter and the frequency converter with a DC link (independent current and voltage inverter) were elaborated. Mathematical...
Modeling IoT systems behaviors and architectures requires new approaches to be elaborated for handling the challenging issues such as: large scale interaction and real-time reconfiguration. This can help both during the design and the operation steps for ensuring a correct design and for delivering a performant service. Different studies have been recently conducted and new initiatives, at the national,...
The operation of the off-grid system consisting of projectable PV panel array and two dieseis (one in reserve) generators SDMO J200K with 160 kW installed capacity are considered in this article. The aim of the study is to make a stability analysis of the system with an evaluation of problems can occur and their possible solutions, which keep the system operational. Three possible faults at generator,...
In this article, authors developed a model for one particular example of microgrid and considered possibilities to integrate solar panels and power storage into existing grid with diesel generator. The choice of configuration is described and power Quasi-Dynamic simulations are performed for the verification of the model. This paper mainly focuses on reliability issues and considers probability of...
A belt weigh feeder system is an electro-mechanical system consisting of variable speed flat belt conveyor designed for feeding bulk material in the process in a controlled fashion. The dynamic weight of bulk material on the belt is measured with a belt weigh bridge and the belt speed is controlled to compensate for the variation in weight so that the feed rate is maintained constant. The problem...
This study presents the control scheme model of a micro-hydrokinetic turbine system equipped with a permanent magnet synchronous generator (PMSG). A power conversion system model is developed to allow a variable speed hydrokinetic turbine system to generate constant voltage and frequency at variable water speeds. A DC-DC boosting chopper is used to maintain constant DC link voltage. The DC current...
A large number of studies have found seasonal and temporal variability in leaf photosynthesis parameters in different crops. This variability depends upon the environment, the developmental stage of the plant and the presence or absence of sinks. Girdling removes the bark and phloem down to the youngest xylem all around the stem and prevents export of photoassimilates out of the stem. This technique...
This paper presents a method for determination of breakdown voltage characteristics (BDV) of a gas-insulated switchgear (GIS) disconnector. The method is applicable for modeling very fast transient overvoltages that are generated during the disconnector opening and closing operations. The method is based on full-scale measurements, as typically performed during the disconnector development and/or...
Thermal power plants are the most common source of electricity generation. To save limited fuel resources and reduce the production cost, power sectors need to face to the most fundamental challenge, which is improving electricity generation efficiency. Modelling the power generation process is the most direct, essential and accurate way to provide necessary information for solving this problem. This...
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