Speed control of wind turbine permanent magnet synchronous generator using back-to-back converter

The utilization of renewable energy sources is becoming increasingly important in terms of energy efficiency and the effectiveness in recent years. Wind energy is one of these energy sources. Wind energy is commonly used in terms of cleanliness of the environment since its reliability and inexpensiveness is increasing more and more. An indisputable fact that the contribution of fossil fuels in electric power generation. However, the gradually depletion of these fuels increases the importance of wind energy. An important part of electrical energy is supplied by wind energy especially in the European countries as Denmark, Portugal, Spain and Germany The grid connected electricity generation from wind energy in Turkey started in 1998 and particularly since 2005, after the advent of the Law No. 5346 Renewable Electricity Law, is reached 1691,8 MW at the end of 2011 increased by over 100% every year with installed capacity and power generation. Then, It is reached the end of 2012 which corresponds to 4% of Turkey's total installed capacity reached 2,261 MW [1], [2]. Several wind turbines are designed to convert wind energy to electrical energy is available all over the world. This one is the most suitable and the most efficient for use in wind turbines, variable speed wind turbines. There is an electric machine which converts to electrcity energy from wind energy, operated as generator, in the structure of wind turbine. In this thesis, speed control with power electronics circuits of permanent magnet synchronous machine that is one of the machines used in wind turbines and is used commonly in recent years, and the operation as generator in determineted speed is simulated in Matlab/SİMULİNK. In the first chapter of the thesis, as a result of the review of the literature, it is given on brief informations about the studies which is made on the subject of the this thesis, the thesis?s purpose and hypothesis. In the second chapter, it is given the theoretical knowledge about wind energy, wind turbines and synchronous and induction generators used in these turbines and it is compared synchronous and induction generators with their advantages and disadvantages. In the third chapter, it is detail described structure, function, business logic, the mathematical model, advantages and disadvantages of Permanent Magnet Synchronous Generator (PMSG) used in this thesis. In the fourth chapter, field oriented control (FOC) method is decribed used PMSG speed control. In addition, it is given informations about back to back converter and is described PWM control techniques used control of this converter and is simulated in Matlab/SİMULİNK. The fifth chapter covers the simulation results on the subject. Speed of PMSG is controled with fied oriented control method. In this control, simulatin is made for inverter switchings by using individually Sinüsoidal PWM, Space Vector PWM and Histeresis Current Control PWM and the results are compared in terms of features the total harmonic distortion (THD), dynamic response, switching losses, etc. The sixth and final chapter, it is pointed out positive and negative results of the control techniques applied in this thesis.