Single‐phase transformer modeling for inrush ‎currents simulation using differential evolution

Abstract

Accurate modeling of transformer saturation characteristics is essential for analyzing inrush currents and harmonic overvoltages. This paper outlines a straightforward method for correct estimation of the transformer's inrush current where the residual flux effect is considered. The Ι-Λ nonlinear characteristic of transformer core is estimated by the sum of two exponential functions. The differential evolution optimization method is used to identify the parameters of the iron core model including the current flux nonlinear function and the core loss resistance. The objective function to be minimized is the root mean square difference between the measured and calculated inrush currents. The experimental iron characteristic is obtained from the secondary winding voltage and primary winding current waveforms produced during transformer energization. The performance and accuracy of the proposed method have been verified by a close agreement between simulation and measured inrush waveforms for a single-phase transformer.

A new model to study ultra-saturation phenomenon during the energization of a loaded three-phase power transformer and its effects on differential protection

“…So, the standard differential protection is not able to identify the ultra-saturation phenomenon, and the description and control of the ultra-saturation phenomenon is necessary for preventing the false trip of the differential protection. Also, several studies have been carried out to distinguish between the inrush current and the internal and external faults by various algorithms [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], but none has taken the ultra-saturation phenomenon into account. This paper presents a new model for investigating the ultra-saturation phenomenon during energization of a loaded three-phase power transformer.…”

“…Several studies have been carried out to distinguish internal faults from external faults and the magnetic inrush current by various algorithms such as the harmonic restraint and the park transform . Also, some works have used special algorithms such as the support vector machine‐based protection scheme , the self‐adaptive transformer differential protection , the time‐domain analysis of differential power signal , the inner bridge connection , the standard 87T differential protection for power transformer and special power transformer , intelligent hybrid systems , moving windows , S‐transform , time‐frequency analysis , differential evolution , negative sequence analysis , and S‐transform and fuzzy expert systems to distinguish between the transient phenomena. But none of these studies have modeled the ultra‐saturation phenomenon.…”

Modified method for transformer magnetizing characteristic computation and point‐on‐wave control switching for inrush current mitigation

“…In Wiechowski et al, the method presented in Neves and Dommel for implementation and verification in the DigsiLent Programming Language (DPL) was exploited. Ketabim and Naseh proposed a method based on the differential evolution (DE) algorithm to identify the iron core parameters, in which the DE was used to minimize the difference between the measured and calculated inrush current. A method for correctly estimating the inrush current in the transformer was also presented in this work.…”

An Adaptive Approach for Simulation of Inrush Current in Three-phase Transformers Considering Hysteresis Effects

“…In addition, parameter determination of the adopted model is critical for obtaining accurate results. Therefore, modeling of transformers for low-frequency transients and inrush current simulation is still under investigation [4][5][6][7][8][9][10][11][12][13][14].…”