Verification of Utility Requirements on Modern Numerical Transformer Protection by Dynamic Simulation

Power utilities are aware of the specific characteristics and requirements for their network. For this reason, they may require additional functionality from the protective devices and secondary systems included in their power network. Therefore ECEPA requires a number of specific tests to be conducted on the protection system proposed for a particular application to prove the suitability of the proposed protection system for the specific application, as in Xiang (1). Only when all of these tests are successfully passed, the protection system is certified for use in ECEPA’s network. The 500/230kV autotransformers are extremely important power transmission elements in ECEPA’s network. Most of these autotransformers consist of three single-phase transformer units. Protection systems for these autotransformers have to fulfil very strict requirements, which are set down by the utility.