The voltage stability problem of a large number of distributed photovoltaics connected to distribution network is the key issue affecting the safe and stable operation of a power grid. In order to adapt to the access of a high permeability distributed photovoltaic power generation system and improve the dynamic voltage support capability of an active distribution network, a dynamic voltage support strategy for an active distribution network considering the current margin of photovoltaic inverters is proposed. Analyzing the voltage sensitivity of the distribution network, and considering the current design margin of photovoltaic inverters, the strategy can make full use of the maximum allowable current of photovoltaic inverters under a voltage sag fault to maximize the active power output of photovoltaic inverters, thereby improving the short-term voltage stability of the active distribution network. Finally, the influence of the current margin of the inverters on the static var compensation system is analyzed and compared with conventional reactive power compensation systems. The comparison verifies the feasibility and effectiveness of the proposed strategy. This work is supported by the Science and Technology Project of the Headquarters of the State Grid Corporation of China “Research and Application of Industrial System Multi-layer Coordination Anti-defense Technology Adapting to Source-Grid-Load Interaction” (No. 52100218000U).