EXCITATION CONTROL DEVICE AND EXCITATION CONTROL METHOD FOR SYNCHRONOUS MACHINE

PROBLEM TO BE SOLVED: To provide an excitation control device for a synchronous machine, having a power system stabilizer (PSS) that outputs an optimum stabilization signal depending on: change in an external reactance Xcalculated by an estimation method with a relatively small calculation amount accurately and quickly; and change in a state amount (P[synchronous generator active power], Q[synchronous generator reactive power], V[synchronous generator armature terminal voltage measurement value]) at an operation of a synchronous machine.SOLUTION: Control amount detection means detects a control amount of an operation state of a synchronous machine. The detected control amount is inputted to external reactance estimation means, and an external reactance value seen from the synchronous machine is estimated by a Kalman filter mechanism. The control amount of the synchronous machine and the external reactance value are inputted to a power system stabilizer (PSS) to generate a stabilization signal. A target value for a terminal voltage of the synchronous machine which is set by voltage setting means, the control amount detection value of the synchronous machine, and the stabilization signal obtained by the power system stabilizer are inputted to an automatic voltage regulator (AVR), and an ignition angle control signal of a semiconductor rectification device provided in an excitation circuit of the synchronous machine is outputted.