Study On Coordination Control Strategy Of Static Synchronous Compensator In Voltage/Reactive

Voltage/Reactive regulation control of Substation has always been a concern of many people; it's also concerned by every electricity sector. Now widely used based on the "nine-zone" reactive power control strategy, because the voltage and reactive power control devices and control strategies of the contradictions in the actual operation has revealed a serious problem. Fundamentally improve the voltage and reactive power regulation characteristics, proceed not only from the control strategy, but also from the voltage and reactive power conditioning devices to proceed. Actual project needs to find a voltage and reactive power control strategy has important theoretical significance and practical engineering value.Recently, with the development of power electronics technologies, several flexible ac transmission system devices make it possible to control power flows as well as bus voltages rapidly and accurately. Among the FACTS devices, static compensator (STATCOM), an excellent reactive power source and load as well, is an adequate device to control the voltage magnitude in a specific bus. In general, there are tow different types of reactive power control devices that are widely employed in a distribution system. An automatic voltage regulator is usually installed to control the secondary bus voltage of a main transformer at a distribution substation through the action of transformer on load tap changers (OLTC). A shunt capacitor (SC) is installed at the low-voltage bus of the substation to adjust the reactive power flow through the main transformer. Although an already installed ULTC transformer is one of the probable candidates for that coordination, there needs to be an additional coordination controller which substitutes for the role of the present ULTC controller because the present controller assumes that it is the only available controller.