Optimizing the costs of reactive power for the coordinated voltage control service

This paper presents a procedure for minimizing the costs involved with the reactive power - voltage control using the synchronous generators/compensators as ancillary service. The procedure combines an optimal power flow algorithm and the secondary voltage control algorithm, the first aiming to minimize the reactive power costs injected/absorbed by the synchronous generators/ compensators, while the second one assuming proportional loading of the generators with respect to their maximum capability limit. The reactive power of a generator can be controlled by the system operator by specifying a certain voltage at the generator terminals.