Arc grounding faults (AGF) in distribution networks can trigger protection maloperation and secondary hazards. Existing fault models often fail to accurately represent the dynamic characteristics of arc high-resistance grounding faults (AHGF) due to neglected dielectric breakdown and arc heat transfer effects. Additionally, conventional arc suppression methods exhibit poor adaptability under high-resistance conditions. To address these issues, this paper proposes an AGF model incorporating heat transfer effects and a hybrid arc suppression method. A grounding resistance model is established that integrates dielectric breakdown characteristics with temperature-dependent resistivity. A variable- dimension Mayr-Cassie arc model with thermal coupling is developed. A series-connected hybrid topology combining passive and active arc suppression is designed to reduce active suppression’s active power consumption. Finally, experimental and simulation results based on MATLAB/Simulink and real distribution network AGF tests with three typical grounding media (birch, red soil, and concrete) demonstrate that, the proposed AGF model can accurately represent fault characteristics, achieving full-cycle current waveform correlation coefficient of 0.8734~0.9173. The proposed hybrid arc suppression method can effectively and reliably suppress various AHGF faults.