Patent ID: 6337561
Filing Date: 2002-01-08
Classification: H02P

Abstract:
An apparatus for stabilizing a power system, to be incorporated into an excitation control system of a rotating type generator in order to attenuate power fluctuations, said apparatus comprising:a short-cycle stabilizing section for computationally determining a short-cycle stabilizing signal for suppressing short-cycle power fluctuations in accordance with a rotational speed signal of a rotor of said generator and an active power signal of said generator; a long-cycle stabilizing section having a stabilization function including a phase compensation function adapted to compensate a phase delay relative to the rotational speed signal of said rotor so that said rotational speed signal is in phase with a phase angle signal of said rotor, for computationally determining a long-cycle stabilizing signal for suppressing long-cycle power fluctuations having a cycle time longer than short-cycle power fluctuations according to the rotational speed signal of said rotor, wherein, said long-cycle stabilizing section has a replacing section adapted to replace said rotational speed signal with at least one of, a signal of the frequency of the voltage of said generator, a signal of the electric current of said generator, an active power signal of said generator, a rotational speed signal generated by combining a signal of a guide vane opening of a water wheel linked to said generator and the signal of the active power of said generator, a rotational speed signal generated by combining a signal of a valve opening of the turbine linked to said generator and the signal of the active power of said generator, an internal phase signal of the generator generated by combining the phase angle signal of said rotor and a voltage phase signal of said generator, an internal phase signal of the generator generated by combining the voltage signal and a current signal of said generator, a phase angle signal of said rotor generated by combining the active power signal of said generator and the voltage signal of said generator, and an internal voltage phase signal of the generator generated by combining the voltage signal and the current signal of said generator; and an output section for producing a sum signal of said short-cycle stabilizing signal and said long-cycle stabilizing signal, and outputting the sum signal to said excitation control system.