Study of material characteristics of core and winding to minimize losses on power transformer

Abstract

Power transformer has an important role in a transmission system. One factor that can reduce efficiency in the transmission system is transmission losses. Efficiency can be increased by reducing losses in the power transformer. The biggest influence determining the losses on the transformer is the material characteristic used by the transformer itself. To get maximum efficiency, it is necessary to optimize the materials on the transformer to get the lowest losses. The study is conducted by measuring core losses and copper losses on the 60 MVA 150/20 kV power transformer with the specified specifications. Furthermore, the transformer materials are changed into several types and the losses calculations are done. The calculation results are compared to get the most effective material. The results show that in the calculation of core losses, the core material type with the lowest core loss value is NK E-core of 0,49 Watt/kg. While in the calculation of copper losses, the winding material type with the lowest loss value is Continuously Transposed Conductor.

Analysis of Inductive Displacement Sensors with Large Range and Nanoscale Resolution

“…Equation ( 3) is the traditional analytical model for calculating the inductance sensor, and the inductance obtained does not consider the leakage inductance. By adding the Equation (11) to Equation (3), we can obtain a modified analytical model of inductance vs air gap characteristic: The calculation of leakage inductance with FEM is cumbersome and time-consuming, and the FEM model cannot be established before the preliminary design of geometric parameters is completed. Therefore, the FEM model can only be used for analysis, not for design.…”

“…Equation ( 3) is the traditional analytical model for calculating the inductance sensor, and the inductance obtained does not consider the leakage inductance. By adding the Equation (11) to Equation (3), we can obtain a modified analytical model of inductance vs. air gap characteristic:…”

“…Core loss mainly includes hysteresis loss and eddy current loss [11], which can be embodied as the equivalent hysteresis loss resistance R h and the equivalent eddy current loss R e resistance parallel to the coil inductance L * , respectively [12,13]. The equivalent circuit of an inductive coil is shown in Figure 13a, where R c is the DC resistance of sensor coil and C is the parasitic capacitance.…”