Based on the sixth-generation 650 V SiC Junction Barrier Schottky(SiC JBS) diode and the third-generation 900 V Silicon Carbide Metal-Oxide Semiconductor Field-Effect-Transistor(SiC MOSFET), the single event effect, total dose effect and displacement damage effect of SiC power devices are studied. In the 20~80 MeV proton single event effect experiment, the Single Event Burnout (SEB) of SiC power device is accompanied by the generation of wave-shaped pulse current, and the breakdown characteristics of SEB devices are completely lost after irradiation. The accumulated proton fluence that induces SEB in SiC power devices decreases with the increase of bias voltage. In the single event effect simulation of SiC MOSFET, when heavy ions are incident on the device from the source, there exit a shorter SEB occurrence time and a lower SEB threshold voltage. The gate-source corner and the substrate-epitaxial layer junction are SEB sensitive regions of SiC MOSFET. The coexistence of strong electric field strength and high current density leads to excessive lattice temperature in the sensitive regions. When studying Co60 source total dose effect for SiC MOSFETs at gate bias (UGS=3 V, UDS=0 V), more serious electrical characteristics degradation occurs compared to at drain bias(UGS=0 V, UDS=300 V) and zero voltage bias (UGS =UDS=0 V). Using the middle-band voltage method, it is found that the vertical electric field in the oxide layer under gate bias increases the generation rate of trapped charges and exacerbates the degradation of threshold voltage. The neutron displacement damage leads to the reduction of forward and reverse currents in SiC JBS diodes. The neutron displacement damage effect experiments are carried out under the drain bias, and the electrical characteristics of SiC MOSFET are degraded the most significantly. This work provides a certain reference and support for the research on the radiation effect mechanism and radiation hardening of SiC devices for space application.