Naslov
French utility investigations for simulating HF transients in power transformers

Autori
Poujade, Paul ; Jurisic, Bruno ; Moreau, Olivier ; Ryadi, Muhamed ; Xemard, Alain

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
CIGRE Pariz / - Pariz, 2018, 1-10

Skup
CIGRE Paris Session 2018

Mjesto i datum
Pariz, Francuska, 26.08.2018. - 31.08.2018

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Transformer ; high frequency model ; complex permeability ; EMTP ; measurements

Sažetak
Utilities conduct different types of investigations requiring the use of high- frequency electric transformer models. Within EDF, two types of studies are frequently carried out: • Lightning overvoltage transmission through transformers. The concern is to evaluate its possible impact on the generators or the auxiliaries of the power plant. • Review and checking of the dielectric stresses on the insulation of the windings. This is the reason why EDF has implemented a generic methodology for the development of high frequency transformer models. These models are more accurate and detailed than those commonly used in most EMT-type studies. Hence they are based on 2D magnetostatic and electrostatic automatized finite-element calculations. The magnetic computation makes use of the complex permeability concept to estimate reasonably the losses related to proximity effect (which are highly dependent on frequency), without requiring too much calculation time. Therefore, no empirical formulations are needed, which makes this method very generic. The processing of the method has been automatized as much as possible: the discretization of the windings is calculated automatically by the software program depending on the frequency validity and the level of details (disk, turn…) inputted by the user. Consequently, it will be usable for any transformer winding and core technology. This method automatically generates a model compatible with EMTP based on the state variables, which enables any kind of electromagnetic transient study to be carried out. The results of this work are well suited for studies of the type mentioned previously but could also be used for other studies requiring a frequency dependent transformer model (as for instance diagnostics using Sweep Frequency Response Analysis or other types of fast front overvoltage studies). The paper will detail the principles of the model and then present its validation based on measurements on a mock-up of a real single- phase power transformer reduced model and manufacturer model results on real power transformers. Finally the paper addresses further researches and challenges.

Izvorni jezik
Engleski

Znanstvena područja
Elektrotehnika

POVEZANOST RADA