This paper introduces a complete design and simulation of a controller for the double fed induction generator (DFIG) turbine. The work also included the solar updraft tower (SUT) design to supply Al-Mahmoudia hospital in Baghdad/Iraq. The design includes the daily average load estimation, annual solar irradiance and, temperature monitoring, and logging.
According to the data obtained from the Ministry of Science and Technology, Baghdad has low wind speed. Therefore, the (SUT) has been designed to generate electrical power depending on the difference between the external and internal air temperature. The temperature difference will generate a suitable airspeed to drive the wind turbine, connected to the proposed (DFIG) generators that generate the appropriate electrical power required. The proposed controller of the DFIG is based on (vector control) by using PI control to feed the power of the rotor circuit parts. The (DFIG) consists of two back-to-back PWM inverters connected between the stator and the rotor. This paper's main goal is to design and simulate a controller for two (DFIG's) under various operating conditions driven by a wind turbine, which is rotated by the warm wind effect inside the solar updraft tower. This is to generate maximum power with constant magnitude and frequency of the output voltage. The proposed controller's performance is verified by using a simulation model built using the MATLAB/Simulink software. The simulation results confirm that the proposed controller (Vector Control), using PI controller maintains both the magnitude and frequency of the output voltage stays constant at the nominal values and stabilization irrespective of the wind speed variations and extract maximum output power. In addition, the controller provides (MPPT) to the turbine to generate the maximum power according to the available wind speed. The torque will give the rotor quadrature current (Iqr), which causes speed change according to the working conditions. The results also showed the steady-state and discussed the two different methods (Vector Control, MPPT) of the control strategy (DFIG). MATLAB and Simulink software used for modeling one of DFIG's modules to supply the hospital load of 276 KW. Besides, simulation results show that the controller demonstrates significant improvements in terms of better stability and faster response.
