Tie-Line Power and Frequency Control of Electric Power Systems - Part II [includes discussion]

In a previous paper [ibid., vol. 72, pt. III, June 1953, pp. 562-71], the authors presented the results of a study of the performance of two interconnected steam-electric power-generating areas as affected by frequency and tie-line power controllers. The present paper extends this study to include hydroelectric power generating areas as well. As before, the object is to determine theoretically the best values of controller gains, that is, to find those controller settings that will result in best over-all system performance. The principal criterion of good performance is, also as before, the minimizing of any oscillations in tie-line power or system frequency resulting from load disturbances to either area. Thus, stability, rather than rapidity of response, is preferred, since the system actually is continually being disturbed by small and more or less random changes of load, rather than by the step load change used as a test disturbance in the study.