Research on Improvement of Line Loss Algorithm Based on Three-phase Unbalance Degree

Abstract

Line loss calculation is an important part of power supply company management. However, when the traditional line loss calculation method is used in an area with a relatively unbalanced degree, the calculated theoretical value and actual value will have a large deviation. Therefore, the paper studies the three-phase unbalance and selects the appropriate unbalance algorithm. Through the dynamic acquisition of three-phase load current, the three-phase unbalance degree of the transformer region is calculated. Then according to the unbalance degree algorithm combined with the equivalent resistance method, the formula of the line loss increment under three-phase unbalance is derived. The paper combines this increment into the improved equivalent resistance method to obtain a line loss calculation method suitable for use in unbalanced stations. Finally, the paper calculates the unbalance degree and the line loss increment under the actual example. And calculating the line loss values respectively by the statistical line loss calculation method, the theoretical line loss calculation method based on the equivalent resistance method, and the theoretical line loss calculation method based on the equivalent resistance method. The comparison shows: The proposed algorithm is closer to the actual line loss than the traditional line loss algorithm. The algorithm in this paper is more accurate and effective, and it can reflect the actual operation. Therefore, in areas where the three-phase imbalance is more serious, the algorithm of this paper will have more advantages than traditional ones.