Table 4: Performance comparison of the modified IEEE-118 test system for four different operating modes.

The two casesOperation modesLoad margin (p.u.) Iteration numbersCPU time in seconds

AC/DC system14.61881529.7642
AC/DC system24.87501532.0300
AC/DC system34.86251531.2754
AC/DC system46.2750 1576.4324