Control system of wind power generator, wind farm, and method for controlling wind power generator

Abstract

A wind power generator generates power through a rotation of a rotor and is interconnected, and operated with its power generation output previously limited in order to be able to further supply the power to a power system in response to a decrease in system frequency. Thus, a concentrated control system derives a required restricted amount corresponding to a power generation output required to respond to the decrease in system frequency, derives a value by subtracting an amount corresponding to a latent power generation output with which the power generation output can be increased, from the required restricted amount, and sets a restricted amount of the power generation output in each wind power generator to perform the operation with the power generation output previously limited to respond to the decrease in system frequency, based on the above value.

1 . A control system of a wind power generator interconnected to a system to generate power through a rotation of a rotor, and operated with its power generation output previously limited in order to be able to further supply the power to a power system in response to a decrease in frequency caused in the power system, comprising:
 first deriving means for deriving a required restricted amount corresponding to a power generation output required to respond to the decrease in frequency of the power system;   second deriving means for deriving a value by subtracting an amount corresponding to a latent power generation output that the power generation output can be increased with, from the required restricted amount derived by the first deriving means; and   setting means for setting a restricted amount of the power generation output to perform the operation with the power generation output previously limited, to respond to the decrease in frequency of the power system, based on the value derived by the second deriving means.   
     
     
         2 . The control system according to  claim 1 , wherein
 the latent power generation output includes at least one of a power generation output obtained from inertial energy possessed by the rotating rotor, a power generation output obtained from an overload operation performed at a rated output, and a power generation output used for charging an electric storage device.   
     
     
         3 . The control system according to  claim 1 , wherein
 the setting means sets the value derived by the second deriving means as the restricted amount of the power generation output in a case where a rotation speed of the rotor does not reach a rated rotation speed.   
     
     
         4 . A wind farm comprising:
 a plurality of wind power generators; and   the control system according to  claim 1 .   
     
     
         5 . A method for controlling a wind power generator interconnected to a system to generate power through a rotation of a rotor, and operated with its power generation output previously limited in order to be able to further supply the power to a power system in response to a decrease in frequency caused in the power system, comprising:
 a first step of deriving a required restricted amount corresponding to a power generation output required to respond to the decrease in frequency of the power system;   a second step of deriving a value by subtracting an amount corresponding to a latent power generation output that the power generation output can be increased with, from the required restricted amount derived in the first step; and a third step of setting a restricted amount of the power generation output to perform the operation with the power generation output previously limited, to respond to the decrease in frequency of the power system, based on the value derived in the second step.