Study On Wind Power Converter IGBT Failure Analysis And Its Reliability Evaluation

Energy source is one of the important materials base on which human can survive and develop, but large-scale using the traditional energy source represented by fossil fuel energy source has brought two increasingly prominent problem that are the energy crisis and environmental degradation. So the attention of new energy source’s development and utilization is drawed over the world seriously, especially the wind energy, which is made enough eyeballs. Also wind power has been fully developed in recent years. Even so, the wind power generation system often works in complex outdoor environment, and the reliability is still a serious challenge.Wind power inverter is the core control component of wind power system, and also one of the weakest link. Its main challenges on its reliable operation are derived from random variation of wind speed, large temperature difference between day and night, high humidity or sand, and so on. According to the analysis of the working conditions, power device failure is one of the main factors influencing the reliability of the inverter, so the research on failure analysis of power semiconductor devices is of great practical significance.There are lots of factors on power device failure, but the failure related to the encapsulation of power component that is caused by thermal load fluctuation is one of the main factors. So the evaluation of power device thermal load is the prerequisite of evaluating its reliability, and easing the power device of thermal load fluctuations is an effective way to improve the system reliability.In this paper the main work is as following: first, in this paper, based on the basic structure and working principle of IGBT understanding, the mechanism of IGBT failure analysis is studied deeply, then the power loss and the thermal load model of IGBT module are established. Secondly, according to the above the problems which should be paid attention to when power converter main circuit is designed are given; Finally, the reliability of the wind power converter system designed is evaluated based on the reliability of IGBT module, so that it’s useful to the design and operation maintenance of wind power converter.