A weak structure power grid is usually characteristic of weak structure, light load and long transmission distance. The grid of Republic of Congo is taken as an example to analyze special problems existed in the operation of such grids. Over-voltage in operation and the impact of generator integration on weak structure power system are focused. After a detailed discussion, a solving scheme was proposed. The simulation shows that the proposed scheme can ensure the safe and reliable operation of this grid; it can solve the problems existed in the parallel in of the generator. Result of this paper is also of some reference significance for solving similar problems in China.