Design and Compliance of Frequency Drifting Islanding Detection Methods with the IEEE Standard 1547.1

Islanding is one important concern for grid connected distributed resources due to personnel and equipment safety. Preliminary design and performance assessment of inverter-resident frequency drifting islanding detection methods (IDMs) can be done by means of non-detection zones (NDZs) in a load parameter space. However, this tool only reflects the steady-state condition, that is, if the frequency of the islanded system will end up within a normal frequency range, where islanding occurs. It does not provide any information regarding the transient period, which is an important factor for the definition of the load testing points for the IEEE Std. 1547.1. Time domain simulations are used to identify critical load testing points that yield the longest run times. Then, the impact of these load values on the effectiveness of the design of frequency drifting IDMs using NDZ is discussed. As a result, an additional criterion for IEEE Std. 1547 compliance is presented.