It's a new challenge to power system stability and control when wind farm cluster is connected to Power Grid at a substation. This paper presents work that has been conducted to research this impact on power system transient stability. The paper obtained results conducted in a realistic Power System with installed wind generation equal to 950MW. The results are generally positive that wind farm cluster should not create serious dynamic risks if the control strategy of DFIG is to support system during faults by generating reactive power. The system studies were performed using the simulation tools PSS/E. Modeling and simulation experiences for this tools achieved during the study are presented in the paper.