Expert system for sweep frequency response analysis of. Application of variable frequency transformer vft for grid interconnection of pmsg based wind energy generation system. Research on the use of matlab in the modeling of 3phase power systems tawanda mushiri member iaeng, charles mbohwa abstract this paper describes the modeling and simulation library for power systems si1mulation under simulink environment. The variable load current magnitude is modulated at a frequency of 5 hz so that its apparent power varies approximately between 1 mva and 5. The tf model object can represent siso or mimo transfer functions. Blocks definition and links to elements, junctions, systems, testbenches, and utility libraries. Variable frequency transformer model analysis by matlab home automation system scada and power system automation fuzzy logic based flow control distributed control system for industrial automation process dynamics, control and automation using labview irrigation control system pid controllers for industrial process control. We analyze the current signal from the rphase when a 400 kv threephase transformer is energized. The model takes into account the winding resistances r1 r2 r3 and the leakage inductances l1 l2 l3, as well as the magnetizing characteristics of the core, which is modeled by a linear rm lm branch. Response for stability purposes simple model for power system use hvdc alternative can. Hence, this paper aims to explore the possibility of grid integration of pmsg based wtg using vft. Variable voltage variable frequency speed control of. Model and simulation analysis of variable frequency.
In the paper, a closed loop digital simulation model of vft and its control system are developed with matlab simulink and a series of studies on power flow. In order to convert responses from the frequency domain into the time domain, you need to perform an inverse fourier transformation. By default, if a vector x contains only positive integers, then tabulate returns 0 counts for the integers between 1 and maxx that do not appear in x. Modeling, analysis and simulation of vft for power flow control through.
New model variable frequency transformer free download as pdf file. Functionally, the vft is similar to a backtoback hvdc converter. Analysis of variable frequency transformer used in power transfer. A digital simulation model of vft and its control system models are developed with matlab and a series of studies on power transmission between power system networks are carried out with this model. Basically, it is a rotatory transformer whose torque is adjusted in order to control the power flow. Application of variable frequency transformer vft for.
Research on the use of matlab in the modeling of 3phase. The frequency response is computed at the frequencies provided by the vector frequency, in radtimeunit, where timeunit is the time units of the input dynamic system, specified in the timeunit property of sys. Citeseerx modeling, analysis and simulation of vft for. To avoid this behavior, convert the vector x to a categorical vector before calling tabulate load the patients data set. The out power thus generated in vf mode has been practically verified. Create frequencyresponse data model, convert to frequency. Matlab simulation model of vft based power system networks b. This example helps you validate a circuit envelope model using a static analysis in the frequency domain, a time domain simulation, and small signal analysis in cases where the.
The powergui block also opens tools for steadystate and simulation results analysis and for advanced parameter design you need the powergui block to simulate any simulink model containing simscape electrical specialized power systems blocks. In this paper, a simulated model of vft is used as a controllable bidirectional power transmission device that can transfer power inbetween power system networks. A matlabsimulink model to study the performance of the vft for. Real time analysis of vft for asynchronous power flow control. This project report deals with the harmonic analysis of single phase inverter with pulse width modulation pwm. Closed loop control analysis of variable frequency. Modeling current signal from an energizing transformer. Ppt presentation on variable frequency transformer youtube. Variable frequency transformer vft is used as a controllable bidirectional transmission device that can transfer power between asynchronous networks and functionally is similar to backtoback hvdc.
Discrete variable ratio twowinding ideal transformer. Recently a variable frequency transformer vft has been used as a flexible ac link between two power systems. This transformer model s equivalent circuit considers each of the winding turns separately 4, so simulating and. This paper describes the basic concept of a new model variable frequency transformer nmvft. This example shows how to create a time series model and use the model for prediction, forecasting, and state estimation. The matlab simulink model developed is successfully used to demonstrate the real power flow from the pmsg to the grid. Pdf recently a variable frequency transformer vft has been used as a flexible ac. A variablefrequency transformer vft is used to transmit electricity between two asynchronous or synchronous alternating current frequency domains. Modelling and simulation of stepup and stepdown transformers. Variable frequency transformer vft is identified as a flexible ac. I have briefly covered the underlying theory and concepts, not with the aim of writing a textbook on circuit analysis and electronics. The simulink model for both simple and practical inverter has been simulated in matlab.
Expert system for sweep frequency response analysis of transformer using matlab jitendra kumar, dr. Display the first five entries of the height variable. Short circuit test of transformer lets say, voltmeter reading is vsc. Introduction variable frequency transformer vft is a. In this paper a straightforward model is proposed for transient analysis of transformers. Variable voltage variable frequency control of threephase induction motor in closed loop is the significant feature of the thesis work. Matlabsimulink software to study the dynamic performance of the vft when. The measurements were performed by sydkraft ab in sweden. It stores the equivalent simulink circuit that represents the statespace equations of the model. Transformer testing and analysis using matlabsimuink. The simscape electrical specialized power systems fundamental blocks measurements library contains an impedance measurement block that measures the impedance between any two nodes of a circuit.
New model variable frequency transformer electromagnetic. This paper presents a novel lumped parameter high frequency circuit model of transformer using emtp analysis of transients within the windings. We assume here that the initial state, this frequency is the nominal frequency. Detailed model of a 100kw gridconnected pv array duration. Optimized modeling of transformer in transient state with.
Variable frequency transformer vft is a controllable bidirectional transmission device that can transfer power between asynchronous networks. It avoids both hvdc link and facts based power transmission control system. Pdf modeling and simulation the current transformer for. Index terms variable frequency transformer vft, asynchronous, new model variable frequency transformer nmvft, vf control, matlab. The topics covered in part ii are dc analysis, transient analysis, alternating current analysis, and fourier analysis. The different features of matlab toolboxes used in the analysis of power systems are described. Basically, it is a rotating transformer whose torque and speed are adjusted to control the power transmission. Ac and dc sources, breakers, transformers, rlc branches and loads, transmission lines. Harmonics introduction to harmonics symptoms expected harmonics from vfds harmonic resonance. Lumped parameter electromagnetic modelling approach. Transformer testing and analysis using matlab simuink. We have an excellent collection of ppt presentation. Basically, it is a rotatory transformer whose torque is adjusted in.
Latest technical seminar topics for electrical engineering. Lumped parameter electromagnetic modelling approach for. Abstractvariable frequency transformer vft is a controllable. Create a frequency table for a vector of positive integers. The model is capable of representing the impedance or admittance characteristics of the transformer measured from the terminals under different terminal connections up to approximately 200 khz. Frequency table matlab tabulate mathworks united kingdom. The third technique facilitates smallsignal analysis to obtain the frequency response of a filtering system that exhibits nonlinearity at a given operation point. If a utility transformer is provided, the pcc is most likely on. Variable frequency transformer vft is used as a controllable bidirectional transmission device that can transfer power between asynchronous networks and func slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. Transfer functions are a frequency domain representation of linear timeinvariant systems. Environment block for simscape electrical specialized. Signals can be considered as the impulse response of an autoregressive linear model, and can thus be modeled using tools such as ar data for signals can be encapsulated into iddata objects, by setting the output data of the object to the signal values, and leaving the input empty. Get the attractive ppt presentation on variable frequency transformer from. Modeling and simulation the current transformer for measuring current harmonics using matlabsimulink.
Variable frequency transformer matlab simulink projects phdprojects. For instance, consider a continuoustime siso dynamic system represented by the transfer function syss nsds, where s jw and ns and ds are called the numerator and denominator polynomials, respectively. This algorithm allows multivalued hysteresis behavior to be represented. Modeling and simulation of threephase power transformer. Model ideal frequencyindependent couplers with sparameters divider model ideal frequencyindependent dividers combiners with sparameters. Variable frequency transformer facts technology for. The linear transformer block model shown consists of three coupled windings wound on the same core. Variable frequency transformer vft which is a new grid interconnection.
Closed loop control analysis of variable frequency transformer vft. The present describe a method to teach power system engineers how to represent the hysteresis in current transformer modeling. Variable frequency transformer vft is a controllable, bidirectional transmission device that can transfer power inbetween power system networks. Analysis and simulation of a dstatcom for voltage quality. Citeseerx document details isaac councill, lee giles, pradeep teregowda. The input power during test is indicated by wattmeter reading. Lumped parameter electromagnetic modelling approach for transient. The initial state of power electronic devices diodes, thyristors, and so on is considered to be open, unless a nonzero. Its various parameters such as r,c and filter design.
The model is simple, so that the simulation with this model is easy and fast. The for loop can be vectorized, which is the matlab way to do something like that. Simulation1 three phase inverter and variable frequency drive simulation with matlab simulink duration. The core technology of the vft is a rotary transformer with threephase windings on both rotor and stator. The results obtained are compared with the results obtained by matlabsimulink. Learn more about high frequency transformers, bidirectional dcdc converters. I have to use a high frequency transformer, which i believe can be implemented by using a ferrite core in hardware. The model which has been developed based on transformer. A digital simulation model of nmvft and its control system are developed using matlab. I dont have matlab at hand, so i cant do it for you, unfortunately.
The names of the electrical state variables, inputs, and outputs are returned in three matrices. Pdf modeling and simulation of variable frequency transformer for. Firstly threephase induction motor drive system is simulated in various modes using matlab xilinx, then. For example, if xt represents a signal to be modeled, then the corresponding. Nmvft and its control system are developed using matlab. Modeling and simulation of variable frequency transformer.
Abstract variable frequency transformer vft is used as a controllable bidirectional transmission device that can transfer power between asynchronous networks and functionally is similar to backtoback hvdc. The variable frequency transformer vft is a controllable, bidirectional transmission device that can transfer power between asynchronous networks. Abstract variable frequency transformer vft is a controllable bidirectional transmission device that can transfer power between asynchronous networks. Estimate frequency response and spectrum using spectral analysis with frequency dependent resolution. Lets consider that you load the data from the first file into the variable magnitude and from the second file into variable phase. Harmonic distortion from variable frequency drives harmonic distortion from variable frequency drives. Generating a variable frequency sine wave in matlab. Pdf new model variable frequency transformer nmvft a. Variable frequency transformer matlab simulink projects.
871 711 1561 1168 1116 1100 729 1231 155 1211 477 1198 687 650 1491 504 1163 719 579 524 265 1085 1174 1207 604 751 1084 1356 1192 657 1068 666 1556 1151 940 1124 1476 1234 486 756 444 914 352 1448 640 849 943 1376