The current status of the research on electrodynamics in electro-impulse de-icing (EIDI) system was summarized in this paper;several common calculation models were analyzed.By taking Bernhart-Schrag model

for example

the theoretical basis of electrodynamics model

the establishment of equivalent model and the solution of state equation were expatiated;the correctness of the model was also analyzed.For the simplified system of EIDI composed of circular flat coil and metal flat plate

Bernhart-Schrag model can help to predict the regular variation pattern of current in the coil and the pulse effect under the skin.