The Optimal Configuration of Reactive Compensating Capacity for Traction Substation

The technical and economical index of traction substations are concerned with the reactive power and negative phase-sequence (nps) power. Set up of parallel reactive compensation (PRC) which have combined compensation effects for the reactive power and nps power is the key to the problem. PRC for the positive sequence reactive power of traction load is only related to the total compensating capacity, and not related to the connection mode of transformer and the distribution mode of compensating capacity in every port; however, RPC for the nps power is not only concerned with the power and power factor of traction load, but also with the distribution of compensating capacity in ports of transformers´ secondary side and the features of PRC. According to the characteristic of PRC for traction load, two kinds of optimal configuration schemes for reactive power and negative sequence compensation are proposed, and the general expression for compensating capacity of each compensating port under the two compensation schemes is given. Taking the measured data of a certain traction substation for example, the feasibility of the two proposed compensation schemes is verified.