Capacitors, Condensers, and System Stability

It is concluded that for the type of systems studied, the system stability characteristics are affected very little by the type of kilovar supply chosen for a central source. If a system is designed and operated in accordance with well-established principles, utilizing modern relaying, suitable generator-voltage regulators, and switching equipments, the stability problem can be essentially narrowed down and isolated to those cases involving electrically long lines and hydroelectric generating stations. In this study, a wide numerical range of parameters was investigated, allowing certain conclusions to be deduced. The data can likewise be interpreted for other systems of similar types. For instance, the results of a high-reactance hydroelectric generator and transmission line of a given length can be applied with reasonable accuracy to a longer length of line and a lower-reactance generator. Similarly, the results of a heavily loaded station with a large inertia constant can be interpreted for one lightly loaded having a smaller constant. Refer discusssion in appendix on this subject. It follows therefore that if certain general conclusions can be reached for the particular systems studied over a wide range of parameters, the same general conclusions can be applied judiciously to other systems of the same type having different voltages, length of lines, machine ratings, and so forth. With this thought in mind, it will be appreciated that the range of constants and the variations studied make for more of a generalization than would appear superficially.