AbstractThe purpose of this paper is to derive a systematic procedure for reactive power control to decide the optimal location and size of compensation shunt capacitors so as to improve the system voltage profile. The proposed algorithm for locating the compensators is based on the sensitivities of the reactive power flow of system lines with respect to the reactive power injection at system buses where the reactive power of shunt compensation is considered as an important strategy in controlling voltage stability. After identifying the candidate buses, the problem is formulated as linear programming problem of the minimization of the possibility of voltage collapse and improving the system voltage profile by defining fewer equations and constraints, and saving computer storage and time. A test system is selected to verify the effectiveness and to confirm the accuracy of the proposed method. We therefore conclude that the practical application of this technique would enhance the security of a power system by reducing the risk of voltage collapse.