Excitation controller and excitation control method for stabilizing voltage in electric power system

摘要

An excitation controller sets an output terminal reference voltage (VGref) of a synchronous machine (21) from a reactive current (IQ) output from the synchronous machine (21) and a high side reference voltage (VHref) of a transformer (22), and controls the field current to be supplied to the field winding (32) of the synchronous machine (21) in response to the deviation between the reference voltage (VGref) and the output terminal voltage (VG). This makes it possible to solve a problem of a conventional excitation controller in that although it can maintain the transmission voltage (VH) on the transmission bus (5) at a fixed value, an expensive PD (10) is needed for detecting the transmission voltage (VH) on the transmission bus (5), which increases the manufacturing cost of the excitation controller.