1.School of Electrical and Information Engineering,Changsha University of Science ＆ Technology;2.State Grid Hunan Electric Power Company Zhuzhou Power Supply Company
The main line of the 10kV line has a single-ended injection bus function, and the end is prone to low voltage problems. The main line pressure drop constraint can be transformed into the outgoing load constraint, which can provide great convenience for safe operation and planning. Therefore, this paper studies the estimation method of the first-end load security region boundary. Aiming at the numerous station loads along the line, based on the segmented pressure drop characteristics, a torque method for rapid estimation of the pressure drop across the main line is proposed; the actual station load distribution is equivalent to the characteristic form of balanced distribution along the line with several heavy load points, which is more consistent The actual situation: Based on the moment method, the relationship between the load at the head end of the line and the pressure drop is obtained, and then the linearized equation of the safety zone boundary of the head load is obtained. The results of the calculation examples show that the pressure drop analysis and safety zone boundary analysis of the moment method can meet the engineering accuracy requirements. Based on the boundary of the first-end load safety zone, the load margin of the 10kV line can be obtained, which is convenient for load control and rolling distribution network planning, and has good engineering application value.