Electron paramagnetic resonance (EPR) has been used for investigation of intrinsic defects in 4H and 6H SiC. At W-band frequency (similar to 95 GHz), the detailed structures of most of the EPR spectra in 4H and 6H SiC irradiated with electrons have been observed. We report our observation of two new EPR spectra, labelled EI1 ' and EI3 ', which are other configurations of the vacancy-related EI1 and EI3 centers. The transformation from the EI1 and EI3 centers to the EI1 ' and EI3 ' configurations, respectively, can be realised by annealing. Two new EPR spectra, labelled EI5 and EI6, with trigonal symmetry and spin S=1/2 were observed in irradiated p-type material. The EI5 and EI6 centers can be identified as the C vacancy and Si antisite in the positive-charge state.