The successful implementation of Flexible Alternating Current Transmission System (FACTS) devices has resulted in a new control mechanism for power systems' safe and efficient functioning. A preventative security-constrained power flow optimization approach incorporating Voltage Adjusting Rheostat (VAR) control modes is proposed in this work to make full use and increase the economic efficiency and static security of a power system. A Predictive Cross Difference Progression Optimization (PCDPO) approach with VAR control is first introduced for power flow computation. The contributions of the static VAR compensator (SVC), Thyristor-Controlled Series Compensator (TCSC), and Thyristor-Controlled switching reactor (TCSR) in this coordinate control are compared, and the case the situation where no FACTS devices are inactivity are illustrated. The optimization model is then built by selecting a minimum system operation cost and a maximum static security margin as the goal while accounting for the impact of three different VAR management strategies on power flow distribution after an N-1 contingency. The Predictive Cross Difference Progression Optimization (PCDPO) algorithm, which is based on this model, is used to optimize the power system operating parameters and VAR control technique simultaneously. Finally, the proposed method is shown using a standard IEEE 30-bus system, demonstrating that it fully uses the capability of static VAR control and significantly enhances the power system's economic efficiency and static security. The proposed model was designed and implemented in the matalb2017a program to examine power flow optimization.