Determining the effect of temperature on microinverter inversion efficiency

Sandia National Laboratories is working to develop a set of test procedures and characterization models which may be used to describe the performance of AC modules and serve as a basis of product comparison. However, in measuring the module/microinverter system output, it is difficult to determine the effects of correlated parameters on system performance. In particular, we have found that the module temperature and the inverter temperature are highly correlated when the system is operating, and thus it is difficult to separate their effects on system power output. In 2014, we have conducted temperature testing on microinverters and we will show that the effect of temperature on microinverter performance is sufficiently small to justify omitting it from the final characterization model for AC modules.