International Aegean Conference on Electrical Machines and Power Electronics / Electromotion Joint Conference, İstanbul, Türkiye, 8 - 10 Eylül 2011, ss.115-119
Different types of generators are used in wind farms including Synchronous and Asynchronous generators and Double Fed Induction Generators (DFIG). In Synchronous generator case, a power electronic circuit called a cyclo-converter is used as an interface to connect the generator to network. This circuit uses a DC-AC inverter with controllable switches that implies the proper and fixed amplitude and frequency in the output. This paper proposes a new method to minimize the harmonics amplitude that contains the firing angles control and a three-phase coupling transformer. In this method, 11 firing angles are defined for every bridge in a quarter of cycle. Then all the harmonic amplitudes is calculated as a function of 01 to On. Then an objective function is defined as a complex of unwanted harmonics (except the even harmonics, and triplen harmonics that are eliminated with the coupling three-phase transformer). This objective function is minimized with numerical methods, to find the optimized values of theta(1) to theta(11). All of this calculation are redone for some admissible amounts of V& in a bounded certain range, and some operating points are gained. A neural networked, trained by these operating points, will have the control of firing the switches after that.