Abstract: Distribution grid static synchronous compensator(DSTATCOM) is an effective means to improve power quality problems such as voltage offset and reactive power. Most of the existing DSTATCOMs use phase-locked-loop based grid synchronous control technology, which has weak dynamic voltage support capability due to the reasons such as phase-locked-loop(PLL) bandwidth and response speed of alternating current(AC) voltage control. To address this problem, an active voltage support method for DSTATCOM is proposed, which uses power synchronization control instead of PLL to realize grid synchronization. The control loop is composed of DC voltage loop, power loop, AC voltage loop and current loop from outside to inside. The reference of reactive power can be adjusted autonomously based on the magnitude of voltage fluctuation to support the voltage of point of common coupling. The reactive power control method with variable integral coefficient can achieve fast power tracking. Matlab/Simulink simulation results verify the effectiveness of the proposed control method.