Based on the research of optimal power flow with transient stability constraints(OTS), optimal power flow with
transient stability constraints and variable clearing time of faults(OPF-TSCC) is proposed. By using a transformed strategy of
constraints, the OPF-TSCC is reformulated to a generalized semi-infinite programming(GSIP). Then a new solution method
based on GSIP is presented. Numerical examples of power systems show the effectiveness of the model and method, and the
new model can be applied to the critical clearing time of faults(CCT) problems.