Voltage and reactive power mode control is performed by dispatcher for the purpose of ensuring required reserves on steady state stability and load stability as well as permissible voltage operating conditions of electric grid equipment. The decision made by dispatcher engaged in controlling reactive power and voltage modes is founded on instructional materials developed in advance for each voltage control station (CS) with focus on data about typical modes of power system or energy area operation. The actual efficiency of reactive power compensation facilities depends on many factors (the composition and operation of grid elements, the composition and operation of generating equipment, etc.). To make final and balanced decision, in some cases, it is necessary to perform some estimation calculations, which take more time for decision making. To minimize and reduce the time required by dispatcher for their decision making and improve its accuracy when involved in voltage and reactive power mode control, it is reasonable to develop software able to determine the efficiency of reactive power compensation facilities in real time.