Static synchronous series compensator（SSSC） is an important AC power transmission device that can damp power oscillation of the system.In this paper

the dynamic adjustment process of SSSC working with synchronous voltage difference with controllable amplitude and phase angle with system power exchange to realize compensation is analyzed on the basis of studying the basic topological structure and mathematical model of SSSC.A power oscillation damping controller with grey wolf optimization（GWO） algorithm is designed.The main parameters of the controller are optimized by GWO algorithm.The power system simulation model with the rated capacity of 100 MVA SSSC is built to simulate the transient conditions such as grid power fluctuation and three-phase grounding short-circuit fault caused by the unstable output power of the distributed generation

which verifies that the SSSC introduced in this paper can play a role.Good damping effect to improve the stability of the power system.