Abstract: The traditional HVDC transmission system is not only prone to commutation failure, but also difficult to maintain stable operation in weak AC systems. With the development of reverse blocking integrated gate commutated thyristors (RB-IGCT), the converter based on RB-IGCTs provides an effective solution to the commutation failure problem. However, existing studies have not adequately assessed the voltage stability of RB-IGCT-based HVDC systems. Therefore, in this paper, based on the quasi-steady state model, the power stability and voltage support capability are analyzed. Secondly, by calculating the critical short-circuit ratio, the ability of the RB-IGCT-based converters to maintain stable operation under the condition of low short-circuit ratios is proved. Then, the transient fault recovery characteristics of LCC and the RB-IGCT-based inverter station under receiving AC faults are studied, respectively. Finally, through PSCAD simulation, it is further verified that the RB-IGCT-based HVDC transmission system exhibits superior small-signal voltage stability and transient voltage stability compared to LCCs in weak AC systems, highlighting their potentials for future HVDC applications.