Single-phase grounding faults in distribution networks can bring significant risks to equipment and personal safety. This study utilizes a combination of the cascaded H-bridge (CHB) and modular multilevel converter (MMC) structures to achieve arc suppression using the voltage arc suppression method. During the fault and arc suppression processes, the injection of zero-sequence components leads to an increase in network asymmetry. This subsequently causes an imbalance in the distribution of active power in the hybrid MMC (HMMC), making traditional interphase capacitor DC-side voltage balancing strategies less effective. Thus, this study analyzes the impact of negative-sequence and zero-sequence components on the interphase capacitor DC-side voltage from the perspective of active power, we propose a control strategy for interphase capacitor DC-side voltage balancing, which is based on negative-sequence current injection. Finally, simulations are conducted to verify the feasibility and effectiveness of this arc suppression scheme and the proposed interphase capacitor DC-side voltage balancing control strategy under arc suppression conditions.