As multi-infeed HVDC systems are integrated into power grid, the operation characteristics of the receiving-end grid have changed remarkably. A large quantity of local generators have to be shut down, resulting in the shortage of dynamic reactive power reserve and voltage support and the downfall of power grid withstanding disturbance capacity. Therefore, it is urgent to install dynamic reactive compensation device such as synchronous compensators. The voltage stability margin, AC fault range causing DC mutation failure, and short-circuit current level before and after installing compensator in the power grid are simulated and comparatively analyzed through simulation software, and the influence of installing compensator in multi-feed receiving-end power grid on system operation is evaluated fully. The research provides effective reference for allocation and parameters selection of synchronouscompensator and makes for promoting the development of synchronous compensator allocation for multi-feed receiving-end power grid.