To eliminate the coupling effect between the two vibration exciters during the fatigue test of wind turbine blades and improve the synchronous control performance of the two exciters, the parallell synchronization control strategy of virtual spindle was designed. The fuzzy PI control algorithm was applied to design a phase controller, and a two-point inertial excitation synchronous control test platform was built to verify the synchronous control effect of the algorithm. The results show that in the non-synchronous control state, there is a coupling effect between the two exciters, and there is a large phase difference fluctuation between the two exciters, which is difficult to realize the joint excitation of the two exciters, and the blade amplitude is disordered and not satisfied the requirements for blade fatigue test; in the synchronous control state, a good synchronous control effect of the two exciters is realized, the blade amplitude is stable, and the phase difference is within ±1.5°.