A hybrid method for voltage stability constrained optimal reactive power dispatch

This paper presents a hybrid method for solving voltage stability constrained optimal reactive power dispatch (VSCORPD) problem. The objective of VSCOPRD is to minimize the energy loss at the current time interval and the cost of adjusting discrete control devices while maintaining system security and voltage stability constraints within the permissible limits. An artificial neural network is trained to approximate the voltage stability margin during the optimization process. A modified ant colony optimization is used to solve the VSCORPD. The numerical results have demonstrated that the proposed method can effectively reduce energy losses, avoid excessive control device adjustments and simultaneously prevent the voltage collapse problem.