PI控制器。 The principleand control strategy of a static synchronous compensator (STATCOM) are analyzed. A nonlinear variable gain fuzzy PI controller for STATCOM was designed via Takagi-Sugeno (T-S) type fuzzy model. The characteristics of the gain variation were parameterized and governed by the rule proportionality. The controller provides suitable voltage control and transient stability enhancement over a wide rang of operating conditions of power system. The transient simulation results on a single-machine infinite-bus system (SMIB) including STATCOM show that the performance of the proposed controller is better than conventional PI controllers.