Power System Stability Control Based On The Signal Of PMU

In power system ,both the transient stability and small signal are Power angle stability focused on by people .If Power system is in defect of some necessary control measures, one local disturbances or abnormal operation could arouse chain reaction of power system . With the establish of WAMS based on PMU , and combined with the decentralized and coordinated theoretics ,the main study for excitation system as follows:1. This paper expatiates on a basic concept of Power angle stability (transient stability and small signal stability) .In order to present through all kinds of control devices can improve the stability of power system , exist disadvantage . These control devices are usually decentralization allocation and control; It is difficult to chew on coordination function between them, in defect of dynamic coordination ability . Only using local information for constituting feedback control, the system oscillation will not be depressed better. So this paper by using signal of wide-area measurements combined with decentralized and coordinated control theoretics design excitation controller.2. This paper instructs the basal principle and constitution of WAMS based on PMU, PMU are the basal factors of WAMS, play a important role in WAMS. And instructs the basal of PMU.3. Instructs the main contents and ideology of decentralized and coordinated theory. And expatiates how design the decentralized and coordinated excitation controller.4. For a simple eight-machine power system, this paper design excitation controller with signal wide-area measurements combined with decentralized and coordinated control theoretics. The mathematic model of multi-machine system is established by programming, and the control law is obtained by calculating Levine-Athans equations. It is simulating in PSASP. In order to compare, designing the decentralized and coordinated excitation controller with feeding back local signal. Finally ,the calculation and simulations proves the decentralized and coordinated controller with signal of WAMS effect on improving the transient stability and small signal stability.