The capacitive coupling between busbars has an effect on ferroresonance occurring on neutral-grounded systems. In this paper
the effect is studied by software EMTP. Results show that the capacitive coupling not only increases the possibility of ferroresonance
but also raises the amplitude of the resonant voltage. It is advised that capacitive coupling may be not ignored when ferroresonance is concerned. In addition
the coupling capacitances among three phases could be taken to be equal in practice.