RESPONSE AND SELECTIVITY IN LARGE TURBO-GENERATOR EXCITATION LOSS DETECTION.

Analyses the response and selectivity of devices used to detect turbo-generator out-of-step conditions by a mathematical model of the turbo-generator and power system elements. Although detection time can be important for highly utilized turbo-generators, detuning from synchronous overswing and asynchronous rotation is determinative. Detection by generator impedance or excitation current with monitoring of the stator voltage is therefore favored, although faster response is considered to be urgently required.