  The constraints induced by prohibited zones (PZs) were traditionally
formulated as multiple disjoint regions. It was difficult to solve the optimal
power flow (OPF) problems subject to the disjoint constraints. This paper
proposes a new formulation for the OPF problem with PZs. The proposed
formulation significantly expedites the algorithm implementation. The
effectiveness of the new approach is verified by different methods including
traditional optimization methods, PSO and particle swarm optimization with
adaptive parameter control which is conducted on the IEEE 30-bus test system.
