新能源转换系统功率模块驱动可靠性分析与试验

目前推挽结构的功率模块驱动可通过减小驱动电阻将导致开通、关断时间的缩短，但同时也将导致开关过程中IGBT功率器件电流、电压热应力的增加，从而使功率模块可靠性降低。对此，在分析功率模块失效机理和热模型的基础上，提出一种基于dSPACE的分段控制算法，通过软件和硬件结合分段控制功率模块开、关断速度。通过实验揭示了功率模块的表面温度变化规律，得出表面温度变化的指数曲线，并证明了该控制方法具有良好的驱动和保护功能，在缩短开关时间的同时可以有效抑制电压、电流应力的增加，并能有效减少新能源转换系统中输出电压和电流的谐波、提高电压利用率和波形质量，使新能源转换系统可靠性得到提高。

Analysis and experiment for reliability of power module driving circuit in renewable energy conversion system

Reducing the driving resistance for the present push-pull driving circuit for power module will make the time shorter,but this process will result in the increase of current and voltage thermal stress. Therefore,a novel driving method based on dSPACE is introduced and validated on the basis of analyzing the failure mechanism and thermal model of power module. The ascending theory of case-temperature is investigated and then an exponential curve is achieved for power module. Experiments prove that the method has a good driving and protective performance,and it effectively reduces harmonics of output current and voltage in the new energy conversion system,and enhances the voltage utilization rate and waveforms quality. Thus the reliability of power module is greatly improved.