IEC 61970-302:2018 specifies a Dynamics package which contains extensions to the CIM to support the exchange of models between software applications that perform analysis of the steady-state stability (small-signal stability) or transient stability of a power system as defined by IEEE/CIGRE Definition and classification of power system stability IEEE/CIGRE joint task force on stability terms and definitions. The model descriptions in this standard provide specifications for each type of dynamic model as well as the information that needs to be included in dynamic case exchanges between planning/study applications.