Solar Loss Disturbance Report Uncovers Reliability Gap in Frequency Measurement Errors
ATLANTA – An August 16, 2016 occurrence in the Western Interconnection resulted in the loss of approximately 1,200 MW of photovoltaic (solar) generation. A joint NERC and Western Electricity Coordinating Council task force investigated this event and found the loss of inverter power injection was due to a perceived low-frequency condition and low-voltage blocking of the inverters. 
The task force produced the 1,200 MW Fault-Induced Solar Photovoltaic  Resource Interruption Disturbance Report, which found that inverters are susceptible to tripping during transients generated by faults on the power system. The report found many of the resources tripped as they used near-instantaneous frequency measurements, which erroneously calculated the frequency.
Posted On: 06/08/2017