EXCITATION CONTROL SYSTEM

摘要

PURPOSE:To suppress the variation in the terminal voltage of a variable speed regulator at system defect time by providing means for calculating the time of applying the strengthened amount of an excitation on the basis of a defect phase, a slip and a machine constant when a defect occurs at a system side. CONSTITUTION:A defect state discriminator 24 judges the phase and the degree of a defect from the voltage and the current of a generator. An exciting phase controller 25 calculates the phase to be strengthened in the excitation from the machine constant, operating state and the defect state on the basis of the signal from the discriminator 24. A calculator 27 takes the difference between a terminal voltage Et and a reference voltage EtO, and a converter 28 converts the output to a slip frequency. A switch 29 is closed when the output of the converter 28 is applied to the excitor. The closing time of the switch 29 is controlled by the output of the controller 25. A calculator 30 adds the exciting amount before strengthening the excitation from the converter 26 and the strengthened amount of the excitation from the switch 29, and supplies it to an excitation amount setter 17.