|Budget Amount *help
¥1,400,000 (Direct Cost : ¥1,400,000)
Fiscal Year 1999 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1998 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1997 : ¥400,000 (Direct Cost : ¥400,000)
As the results of this project, first the method of the equilibrium point control can be summarized as follows :
(1) The control input is chosen to put the unstable equilibrium point as far as possible from the stable one, or to eliminate it. So, the static analysis enables us to get a larger dynamic stable region by adding a linear or nonlinear control input.
(2) It is easy to consider the nonlinearity of generator, and the limiter of controller in power system.
(3) The method is fundamentally a nonlinear control, and it can be expected to control the oscillation including multi-modes.
Second, in the proposed method, by looking over the entire system from each generator-bus, a decentralized system is identified to simplify the problem of multi-machine power system into that of plural robust one-machine systems. Then, equilibrium points of each decentralized system are analyzed, and feedback gains of supplementary control inputs ua and ug for AVR and GOV are decided under the guarantee of stability. Thus, by adding the ua and ug to each generator, the nonlinear decentralized control for the system can be carried out. The method is applied to one-, three-, ten-, and twenty-machine model power systems, and the validity is verified through numerical simulations. Finally, it is shown that control responses and the critical clearing time of the system with the controller can be more improved than the case with PSS by introducing the nonlinear supplementary control inputs for the standard one-machine model system.