Due to the strong development of wind power and lack of investment in the development and revitalization of the transmission network, there is a need for a methodology that will enable the identification of maximum wind power plant integration capabilities into existing transmission network without the need for additional investment in network development, and without significant disruption of relations in the electricity market. The methodology proposed in this thesis is based on one-year simulation of power system operation with wind power plants on an hourly time basis. Simulation represents a complex optimization problem that is solved by iterative solving a series of simple subproblems. In the first subproblem, the order of conventional power plants commitment is determined as well as power distribution on deployed units in the system, based on incremental costs of their production, for each hour of the studied time frame. In the second subproblem, the boundary limit on individual wind power plant installed capacity scheduled for connection to a pre-defined network node is determined, taking into account the limitations of the transmission system under normal and N-1 operating conditions, while considering given (maximum planed) capacites of wind power plant on each location. In order to eliminate a large number of redundant linear constraints in the second-level subproblem enabling its solution, a reduction scheme based on a quick convex hull algorithm is implemented. In addition, since simultaneous wind speed (wind power) data at different locations are often unavailable or not sufficiently long, methods based on vector autoregression and Markov chains that can generate realistic simultaneous time series of wind speed (wind power) data, are developed.