Practical challenges in hybrid simulation studies interfacing transient stability and electro-magnetic transient simulations

This paper discusses practical challenges of interfacing Transient Stability Analysis and Electro-Magnetic Transient Simulation tools in hybrid simulation studies. Various interfacing approaches are examined and single-port Thevenin equivalent is proposed as a suitable and practical solution to represent the TSA-side system in the EMT simulation. The shortcomings of this representation are discussed and a quantitative measure is proposed to evaluate validity of the interface, which helps capturing the cases where the simulation may run into numerical instability due to simple representation of the external system. The effectiveness of the proposed technique is demonstrated using two practical power systems.