An empirical study of compensation techniques for fast decoupled load flow

This paper presents a comprehensive study of compensation techniques used with the fast decoupled load flow (FDLF) method for power systems having branches of low reactance to resistance (X/R) ratios. Both series and parallel compensation schemes have been dealt with. The approach has been to use an empirical investigation to determine the optimal parameters for both schemes. Under optimal conditions the two schemes need the same numbers of iterations for convergence, even if the X/R ratios of some branches are exceptionally bad. The technique can be easily and efficiently used for a variety of problems; no matter whether the branches are radial or looped, distribution lines or three-winding transformers, and LV underground cables or HV overhead lines with series compensation. Moreover, the validity of the technique is not limited by the number of ill-conditioned branches.