Comparison of three different multi-scale models for transmission lines to simulate diverse transients in power systems

This paper presents three main multi-scale transmission line models that are capable of simulating diverse transients. Such multi-scale simulation is achieved by using the methodology frequency-adaptive simulation of transients (FAST). In addition to the time-step size, a new simulation parameter referred to as shift frequency is introduced. Appropriate adjustment of both shift frequency and time-step size allows the integral simulation of electromagnetic and electromechanical transients within the same study. Based on the simulation concept FAST, three different multi-scale models of transmission lines are developed. These models include multi-scale line model with lumped parameters, multi-scale line model with constant distributed parameters, and multi-scale line model with frequency dependence. Case studies are performed to validate different multi-scale line models in terms of accuracy and efficiency. For studying diverse transients, the multi-scale line model with frequency dependence is the best choice.