A System for Connecting the Wind Turbines to Power Grid

Generating electrical energy by the alternative energy resources is getting popular as the cost of generating electricity using alternative energy sources is getting cheaper. One of the most popular alternative electrical energy generation method is the wind turbines. The asynchronous character of the wind turbines creates the problem of integrating the generated wind power to the main grid. Converters are the basic elements of integration. The traditional converters are used for interconnection but any system using a special converter that would enable the use of three lines at the same time for dc transmission was not introduced. This paper introduces a new HVDC system using star-delta converter which enables to integrate wind turbines with the main power grid. The converter introduced has three additional valves enabling three dc terminals at the output of the rectifier. The rectifier and inverter are used to design the system for wind turbines to be connected. The system is tested by modeling with PSCAD/EMTDC software for operation and dynamic stability. The results obtained are compared with the system build by traditional converter under the same conditions. The paper also proposes alternative applications for the same system.