A risk assessment method for transmission network considering the influence of substations

Abstract

A transmission network risk assessment method considering the influence of substations. The method first collects the reliability parameter data of the regional power grid and the internal components of each substation and the basic parameter data of the internal relay protection of the substation; then establishes the Marko of the internal components of the power grid and the substation The state model and the hidden fault model of relay protection are used to determine the occurrence probability of each state of components and relay protection; then the improved non-sequential Monte Carlo simulation method is used to sample the system state; finally, the load shedding based on DC power flow is adopted The optimization model analyzes the load loss risk of the system state, calculates the risk index of the transmission network, and evaluates the risk of the transmission network according to the risk index. The invention can reflect the influence of the substation on the risk assessment of the transmission network to the greatest extent, further improves the accuracy and real-time performance of the risk assessment on the premise of satisfying the calculation accuracy, and can provide reliable basis for the grid operators to understand the real-time risks of the grid.

Description

technical field [0001] The invention relates to a method capable of accurately evaluating the operation risk of a power grid, and belongs to the technical field of power transmission and distribution. Background technique [0002] In the power system, as a key link in the power grid, the substation undertakes the power supply task from the transmission network to the user, and its main wiring directly affects the safety and stability of the power grid and the reliability of power supply. Therefore, it is of great practical significance to study the risk assessment method of transmission network considering the impact of substations. [0003] In the actual power grid, due to the mutual influence between the substation and the grid, the reliability of the substation with the same wiring form may vary with the role and position of the substation in the system. Therefore, the impact of substations on the power grid should be considered when evaluating system risk from the persp...

AI Technical Summary

Problems solved by technology

At present, the transmission network risk assessment methods considering the impact of substations can be divided into two categories. One is to analyze the reliability of the main wiring of the substation first, and then equivalent it to a bus node with a probability of failure, so as to realize the connection between the main wiring of the substation and the transmission network. This method not only improves the evaluation speed of the power grid, but also dilutes the impact of the main wiring of the substation on the power grid; the second is a hybrid method that combines the analytical method and the Monte Carlo simulation analytical method. First, the minimum cut set method is used to obtain the substation On this basis, the state sampling of the equipment in the transmission network is carried out, and the risk index of the entire transmission network is calculated after the simulation of the specified time is completed. This method is difficult to simulate the randomness of the internal component failure of the substation, and in the same The calculation accuracy is more time-consuming

Therefore, the existing transmission network risk assessment methods considering the impact of substations are not ideal in terms of assessment accuracy, and further research is needed

Images