As shown in previous studies, the pulse train complexity enhances the efficiency of directed electromagnetic pulse effects on electronic equipment. Proposed are basic circuit arrangements and a theory of two generator types which are being developed for high-power electromagnetic fractal pulse sequence generation. Pulse generation occurs owing either to break in the electron current loop, powered from inductive storage, or to charge dumping and transitions between quasi-steady states in the virtual cathode (vircator) diode system. The generation process is controlled by a binary sequence which corresponds to the time series with the fractal properties. The current fractal pulse train leads to generation of the electromagnetic fractal pulse sequence.