SUPERVISORY CONTROLLER FOR SAFETY LIMIT OF GENERATOR

PURPOSE:To perform supervisory control easily with high accuracy by providing means for detecting the terminal voltage of a generator, means for operating the margin of stability, and an adder for adding a control amount to the exciter for the generator in order to control the field or adding the control amount to a governor in order to reduce the output thereof. CONSTITUTION:A position detector 15 detects direct-axis and quadrature-axis positions of generator pole. A direct-axis and quadrature-axis component analyzing section 10 extracts direct-axis and quadrature-axis components of a basic wave component of generator voltage and current provided from a basic wave component analyzing section 9 through a potential transformer 4. A control operation section 12 operates a margin M based on the direct-axis component of generator terminal voltage and a maximum value thereof. When the margin exceeds a set value, a corresponding control amount is fed to an adder 6. Consequently, a voltage regulator 7 performs regulating operation based on an amount obtained by adding the control amount to the difference between the detected value and the set value of terminal voltage, and performs field control of a generator 3 based on the operated output.