In preparation for the upcoming CAISO Transmission Planning Process Requirement pertaining to the Electromagnetic Transient (EMT) Modeling Guide for Inverter Based Generators (effective May 31, 2019), GridSME has developed a Frequently Asked Questions (FAQ) bulletin to support effected entities.

GridSME has observed that this requirement has created numerous questions for generators within the CAISO footprint. If your facility is a Category 1 or 2 you may be required to submit an EMT model suitable for sub-synchronous resonance (SSR) studies. These FAQs are designed to provide a better understanding of the EMT model requirements.

Questions addressed in this bulletin:
  • What is an EMT Model and what is it used for?
  • How do I know if I have to provide this information to CAISO?
  • What category has the CAISO identified my generating plant as?
  • What information is required to complete an EMT model?
  • What is the format that I need to submit the required data?
  • What happens if I do not comply on time with the CAISO TPP BPM?


  • If you would like more information on how this requirement may impact your organization, don’t hesitate to reach out. We look forward to assisting you with the EMT submission requirements or answering any questions that you may have.