Abstract
Authors defined that the optimum location of an intermediate switching stations in bulk power long distance transmission system is the points where the transient stability is at an average level, from the viewpoint that margin of transient stability varies depending upon the local load and location of fault on the lines. To make this location more useful, fault location and variation of local loads shall be taken into account.
This paper introduces the probabilistic stability index and examines the optimal location of switching stations as follows: (1) The stability probability was extended to handle fault location in continuous manner, istead of discrete way. (2) The optimization index was proposed, which takes the probability with fault location as random variable into account; and the optimum location were analyzed. (3) Considering the time dependence of fault occurrence and load variation, a procedure for evaluation of fault occurrence probability which depends on the load was proposed and its effectiveness was verified. (4) The optimum location of switching station was examined with variation of loads taken into account. To make the optimum location more practical is made possible in this sense.