Considerations in Applying EMTP to Evaluate Current Transformer Performance under Transient and High Current Fault Conditions

With addition of in-plant generation industrial facilities face increased short circuit levels and DC components in fault currents. EMTP is an effective tool in modeling and studying current transformer (CT) performance under such conditions. This paper advances the applications of EMTP for such studies. CT’s models in EMTP may require hard-to-get information at early stages of power system projects. The paper examines approaches to make appropriate assumptions for missing model information and tests the sensitivity of EMTP results to such assumptions. By presenting case studies the paper facilitates such applications of EMTP and supplements an earlier IEEE Work Group on the EMTP modeling of protection CTs.