Transmission system models provide the foundation for our planning process. We build reliability (Powerflow and Dynamics) and economic models annually to support the core planning functions necessary to ensure compliance with our Tariff and North American Electric Reliability Corporation (NERC) standards. We employ a collaborative stakeholder driven process to develop assumptions that ensure appropriate modeling of future transmission system scenarios. Models are also coordinated with our neighboring entities to ensure systems are accurately represented across our seams.

Process and Timeline

Models developed by MISO are used for a variety of near-term and long-term planning studies. On an annual basis, we build models to represent a 10 year planning horizon. The modeling process begins in September and concludes the following August. Stakeholders (data and equipment owners) are responsible for submitting the required modeling data to MISO. Our staff reviews the data for reasonableness, and compiles it into a set of models. Throughout the process, models are reviewed for reasonableness of data and performance. Stakeholders review draft models and provide us with feedback before they become final.

Modeling Process Map

Our Modeling Tools

  • Siemens PTI Model on Demand (MOD) database
  • Siemens PSS/E for Powerflow and Dynamics
  • Ventyx PowerBase database and PROMOD for economic studies

Our Models


  • Current year for summer, fall, winter and spring
  • 2-year out summer peak and light load
  • 5-year out summer peak, winter peak, shoulder and light load
  • 10-year out summer peak load


  • Utilizes the 5-year out summer peak, shoulder and light load, and 10-year out summer peak powerflow cases

  • Economic (PowerBase)

    • Utilizes current, 5-year and 10-year summer topology


    MTEP17 TSAT Dynamic Model Development Schedule

     Date  MIlestone
     03/01/2017  MISO issues dynamics data request
     03/22/2017  Stakeholders complete dynamics updates and send to MISO
     05/08/2017  MISO posts draft TSAT models for review.  Stakeholder review starts.
     05/22/2017  Stakeholders comments on draft models due to MISO
     06/14/2017  MISO incorporates changes from draft review
     06/15/2017  MISO posts final TSAT models

    MTEP18 Economic Model Development Schedule

     Date  Milestone
     01/30/2017  Economic Model Building Kick-off
     02/15/2017  PAC reviews futures
     04/04/2017  MTEP18 Futures Workshop
     06/01/2017  PAC review generator siting methodology
     08/01/2017- 09/30/2017  EPUG reviews Expansion Results & Preliminary Siting
     08/01/2017  PROMOD model posted for stakeholder review
     09/01/2017  Stakeholder feedback on PROMOD model due
     10/01/2017  Finalize MTEP18 PROMOD model


    MTEP18 Power Flow Model Development Schedule




     Responsible     Party


     LSE, TO, and GO data request sent



     Model On Demand reference models posted



     Generator data due to Model On Demand



     Load profiles  due to Model On Demand



     Transmission project , BLG profile, and device profile data due to Model On Demand



     Topology and Load Pass  model posted for review


     10/17/2017 – 11/1/2017

     Review Topology and Load Pass models    / updates to MOD

     LSE, TO, and GO


     Review Pass 3 models posted for review


     12/27/2017 - 01/31/2018

     Review of Review Pass models, respond to data checks  / updates to MOD.

     LSE, TO, and GO


     Final MTEP models completed / posted


     Related Documents

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