Superconducting dynamic synchronous condensers (SDSCs) exhibit significant potential for replacing traditional dynamic synchronous condensers (DSCs) due to their powerful reactive power output capability and low thermal losses, which are attributed to their large short-circuit capacity, high air-gap magnetic density, and low synchronous reactance. This study comprehensively reviews the development trajectory and current research status of SDSC, both domestically and internationally, and conducts an in-depth analysis of their advantages. Based on this, this paper highlights three typical cases of SDSC and summarizes the key technologies of SDSC from the perspectives of the excitation winding, stator structure, rotor magnet, and cooling system. Finally, it proposes that cooling and insulation technology, quench issues of AC windings under magnetic fields, and torque tube transmission technology will be the key technical challenges for future research and resolution in SDSC.