Grid side system GSS model is studied and developed in steady state form by using phasor theory; studying the relationships between active and reactive powers, voltage, and currents at different operating modes. Then, control of the grid side converter GSC is optimized; developing the grid side dynamic model based on space vector theory. In this paper vector control technique that utilizes a rotating reference frame (dq) aligned to the grid voltage space vector is employed. This control algorithm made it possible to achieve the two main objectives of GSC: control of the DC bus voltage and assure transmission of power through the converter (along with controlled reactive power exchange). DC link bus voltage has been controlled using Interval Type-2 Fuzzy Logic Controllers (IT2FLCs). The proposed IT2FLCs were designed to deal with the ambiguity appeard as a result of changes during system operation. In this paper, design of GSC controller, which is responsible for the terminal voltage control in addition to the DC link voltage regulation, is performed. The developed IT2FLC controller is simulated using MATLAB/SIMULINK software for a 1.5 MW typical wind turbine to verify the performance of the controller. |
