Time-domain protection relays have increasingly attracted the attention of electrical power utilities. These relays speed up the tripping process of traditional protection schemes, increasing the stability margins of high-loaded power grids. Among the existing time-domain protection functions, the travelling wave (TW)-based differential protection TW87 has shown to be promising. However, as such a function is relatively new in the relay market, studies on the TW87 performance have been of interest to protection engineers. Thus, this study presents a parametric analysis of the TW87 performance. To do so, massive fault simulations are carried out, considering different fault scenarios and protection settings. From the obtained results, important issues related to the TW87 performance are addressed.