Voltage Security Constrained Optimal Power Flow considering Smart Transmission Switching Maneuvers

To increase the security level and stability of the power systems, high controllability capability is needed. The voltage security margin (VSM) index in power systems can be also affected by various transmission switching (TS) maneuvers. However, one of the major challenges in optimal power flow problems using TS, is that there is no limit to the number of switching on the network over specific periods, thus increasing the probability of a failure occurrence, reducing also the reliability and lifetime of circuit breakers. In this work, a model of optimal power flow (OPF) problem using smart TS concerning the reliability of the CBs to reduce the number of switching and operation costs is presented, formulated with a non-linear function. Thus, a linearization method is implemented to linearize CBs reliability formulation, considering as well locally reactive power compensation devices such as capacitors, allowing more active power flow through the lines to supply more loads. An optimal planning and operation of capacitors can be introduced as another solution to increase the voltage security margin and network loading. The proposed linearized AC power flow model is evaluated in a real case study of the Fars Regional Electric Network in Iran.