Since 1999, our Research Department has released 59 scientific articles about transformer short-circuit calculations, tests, mathematical models, simulations and TRANSFORMER PROTECTOR efficiency to avoid transformer tank explosions and oil fires (list available upon request).
In order to study the energetic transfer phenomenon that occurs during a short circuit in transformers 2 experimental test campaigns were carried out; the first by Electricité de France in 2002 and the second by the Brazilian high voltage laboratory CEPEL, in 2004 on large scale transformers.
These 62 experimental tests consisted in creating low impedance faults in oil filled transformers equipped with the TRANSFORMER PROTECTOR. The tests showed that the arc first creates a huge volume of gas that is quickly pressurized, generating one high pressure peak that propagates through the oil. This First Dynamic Pressure Peak activates the TP within milliseconds preventing the transformer from exploding.
In addition to the experiments, a compressible two-phase flow numerical simulation tool has been developed. The experimental results have been used to validate the simulation model. Adding to this model a dynamic structural analysis package has been coupled to create a fluid structure interaction. These simulations definitively show the efficiency of the TRANSFORMER PROTECTOR to prevent explosion and fire.
The arc used in the simulation, located at the base of the right bushing, has parameters given in the table below and total energy of 7.19 MJ.
|Current(Peak)||Voltage (Peak)||Frequency||Duration||Total Energy|
|2,000 A||80,000 V||50.0 Hz||0.110 s||7.1986 MJ|