Modelling and simulation of wind turbine emulator using DC motor

Abstract

Global warming and increasing oil prices has led the world to discover new energy resources which are environment friendly and are found in abundance so that they meet energy demand of the world. Wind energy is one of the most promising forms of renewable source of energy which can be used to generate electrical energy. In wind technology, a wind turbine is used to convert the kinetic energy of the wind into mechanical energy. Wind turbines are connected to generators with or without a gearbox to produce electricity. A generator is used to convert the mechanical energy coming out of turbine rotor into electrical energy and this energy can be used in standalone systems or with systems connected to the grid. This complete system wind turbine to grid is known as wind energy conversion system (WECS). Wind turbines are large in size and are mounted on a tower at a fixed height hence field study of wind turbines is not easy and physically taxing. Moreover, wind is intermittent in nature and changes continuously with time. Hence the study of wind turbine and its performance analysis under different conditions of wind speed and pitch angle is done by creating a turbine model, which is realised through a dc motor giving the characteristics similar to a turbine. Such a configuration is referred to as wind turbine emulator. In this paper, wind turbine emulator is designed using a separately excited direct current motor operating with a chopper circuit controlled to achieve prescribed wind turbine behaviour through current control of dc motor with a proportional integral (PI) controller. This wind turbine emulator is coupled to permanent magnet synchronous generator (PMSG) to check its performance.