EXCITATION CONTROLLER FOR SYNCHRONOUS MACHINE

PURPOSE:To obtain a response speed equivalent to an output voltage constant (AVR) control of a synchronous machine in a transmission voltage (PSVR) control by controlling an exciter of the machine according to a phase compensated value by altering a constant in response to a control state. CONSTITUTION:A deviation calculator (DM) 9 calculates a deviation of a detected value of an output voltage of a synchronous machine 1 for supplying power to a power system 4 through a booster transformer 2 from a set value. A DM 12 calculates to amplify a deviation of a detected value of a high voltage side voltage of the transformer 2 from a set value and outputs it. An adder 31 adds the outputs of the DMs 9, 12. A control switching contact 23 switches to allow the output of the DM 12 to be connected to or disconnected from the adder 31 in response to a control state. Then, an amplifier 19 amplifies the output of the adder 31, alters the constant in response to the control state, and outputs the phase-compensated value to control an exciter 30. That is, a changeover contact 26 is closed at the time of an AVR controlling to connect a phase compensator 21 to an amplifier 20. A changeover contact 27 is closed at the time of a PSVR controlling, and connects a phase compensator 22 to the amplifier 20.