Computer Simulation of Theoretical Model of Electromagnetic Transient Processes in Power Transformers

Abstract

The paper is presenting theoretical analytical model and computer simulation of electromagnetic transient process in a transformer. Transformer parameters in a selected transitional process have been analyzed. Theoretical model refers to an energetic transformer with concentrated parameters with consideration of parameters of mutual inductance M. Simulation was performed on a personal computer using the software program MATLAB SIMULINK. The computer simulation confirmed the possibility of transitional process analysis in transformer’s windings with concentrated parameters

Graph-Analytical Method of Determining Impedance in Electrical Transformers

“…In this case, the graph-analytical method for the verification of the simulation method [14], which replaces the measurement method, dry power transformer ABB of coupling , power 1; 2; and 3.15 MVA, and the tests with three measurements for active, for capacitive, and for inductive loads are selected (adapted the program psb3phasesignalseq (Figure 3)) [14].…”

Analysis and Estimation of Values of Currents and Voltages at the Disturbances in Induction Machine Using Tested Matlab Simulation

“…Values are defined by standard: for light source and projectors are (-2,2÷+5%) and for all other receivers, including electric machines, are ±5% [4,9]. Small values of voltage asymmetries (±1% is sufficient) create an important values of current asymmetries, of ±(7÷9)% order [4,9].…”

“…Small values of voltage asymmetries (±1% is sufficient) create an important values of current asymmetries, of ±(7÷9)% order [4,9]. Winding temperature of the induction machines   n  in function of asymmetries is dependent on resulting coefficient of voltage asymmetries u  [4]:  is inverse component of the current equal to the direct and no longer plays a subordinate role. At asymmetrical voltage feeding system the thermal losses can be calculated according to the expression:…”

“…In selected mathematical model and with the computer assistance it is possible to determine asymmetry conditions and to estimate the additional losses 3  m of phase-distorted loads arising from the fundamental and higher harmonics of asymmetric voltage and current components [3,4].…”

“…There are two mathematical models for examination of normal and transient processes in the electric machine, electrical and thermal, whose models contain the following quantities: voltage, current, magnetic fluxes, mechanical torques, velocity, and power [4,5].…”