سال انتشار: ۱۳۸۴
محل انتشار: سیزدهیمن کنفرانس مهندسی برق ایران
تعداد صفحات: ۷
Hamid JAVADI – Electrical Engineering Department Power and Water University of Technology (PWUT), Currently at University of Quebec at Chicoutimi (UQAC), Canada
One of the conventional methods to increase the capacity of power transmission lines and also to decrease the corona discharge in the vicinity of the conductor surface is to use conductor bundles. In this case, the high voltage gradient surrounding conductors and the corona losses of transmission lines decrease largely. Calculation of voltage gradient (electric field strength) for bundle conductors is done by changing these conductors into a single one that the radius of this equivalent conductor will be determined by an experimental Req = rb(n.r0/rb) 1/n . In this relation “n” is number of conductors bundled, “r b ” is radius of bundle and “R eq ” is the equivalent radius for a single conductor that yields the same effect as the bundle conductor. All software for electric field calculationsaround the conductor of high voltage bundle transmission lines are based on the above relation. It is evident that the results for the obtained values of electric field on the surface and the points very close to the surface of conductors are far from their actual values. Thus, in this paper, the development of a new formulation which can be used in the traditional algorithm for more precise electric field calculation of bundle conductors is introduced. Theoretically there is an optimum sub-conductor separation for bundle conductors (or radius of bundle) that will give minimum crest gradient on the surface of a sub conductor, hence by using of this formula in developed software, the optimum radius of bundle in point of view to minimize the maximum value of electric field of
various high voltage transmission lines can be determined.