The magnitude and frequency of voltage swings has become difficult to manage as the aggregate number of asynchronous generating resources increases and inverters used to interconnect these resources provide little or no reactive support to the system. PJM anticipates that this may create a planning and operational issue within the eastern interconnection and is interested to act proactively by exploring the issue and developing solutions. To mitigate voltage swings and manage voltage within the allowed operating range, inverters with enhanced functionalities like dynamic power control could be deployed. Enhanced functionalities such as improved fault ride-through capability could also improve system stability during system disturbances when the grid frequency may go outside the normal operating ranges.
To protect the generators, the existing trip setting requirements prescribed in IEEE 1547 include both under and over voltage and under and over frequency limits. However, these limits pose a risk to grid reliability as they prevent generators from staying online during a temporary system disturbance and effectively worsen the impact of the disturbance. New standards may need to be developed to take advantage of the enhanced inverter functionalities to expand the ride-through capability without damaging to generators and to increase reactive support to the system during and after a disturbance.