Reliability Improvement for a High-Power IGBT in Wind Energy Applications

The power command in wind energy conversion systems is subject to wind power fluctuations, which may cause significant thermal cyclings of high-power insulated-gate bipolar transistors and may, consequently, lead to a reduction in lifetime. To address this reliability issue, a model integration is established in MATLAB/Simulink, which includes a doubly fed induction generator (DFIG), an aerodynamic model, a drive train model, and a pitch control system. A detailed model of a three-phase converter is adopted for thermal modeling and lifetime estimation. A low-pass filter is utilized to improve the lifetime consumption of the rotor-side converter control in the active power loop in the DFIG. The simulation results indicate that the resulting reliability performance of the system has been significantly improved. Moreover, the capacity factor has been estimated.