Equivalent three-phase short circuit calculation method which considers outer network ground branch circuit and sensitivity information

Abstract

The invention discloses an equivalent three-phase short circuit calculation method which considers an outer network ground branch circuit and sensitivity information. Firstly, whole-network basic data including system element parameters, a topology structure and a trend calculation result under a normal running condition is input, then based on a sensitivity consistency equivalent method, an equivalent network is constructed, through a sensitivity weighing method, ground branch circuit admittance parameters are deducted, and according to trend, sensitivity and power transfer characteristic consistency, other parameters are solved. Finally, an improved equivalent method is applied to three-phase short circuit calculation, through the adoption of a node impedance method and a superposition theorem and based on the trend calculation result, a short circuit point current under a three-phase short circuit fault of an inner network, all node short circuit voltages and all branch circuit short circuit currents are calculated.

Description

technical field [0001] The invention belongs to the field of transient state analysis of power systems, and in particular relates to a three-phase short-circuit calculation method considering the equivalent value of an external network. Background technique [0002] With the development of the interconnected power grid, the short-circuit current level of the system continues to rise, which seriously threatens the safe and stable operation of the power grid, and the three-phase short-circuit causes the greatest harm. At the same time, the interaction between the interconnected subnets is increasing day by day, and the short-circuit calculation of the internal network must consider the impact of the interconnection and the external network. However, the characteristics of the hierarchical and partitioned operation and management of the power grid and the need to protect commercial secrets make it impossible for the internal network to obtain data from the external network. Int...

AI Technical Summary

Problems solved by technology

In the existing literature, in the static equivalence study of wind farms considering the consistency of tidal current and sensitivity, the precise equivalent parameters of the ground branch in the case of single boundary are obtained through the sensitivity weighting method, but they do not analyze how to solve the equivalence pair in the multi-boundary case. Dizhi Road

Images