Dynamic security region practical and rapid algorithm considering trip time difference of two ends of line

Abstract

The present invention discloses a dynamic security region practical and rapid algorithm considering trip time difference of two ends of a line. The algorithm comprises: determining and considering the dynamic security region of a fault clearing time difference, and employing a fitting method to calculate a base hyperplane coefficient, wherein the hyperplane linear relation expressions in the fault clearing time are a0y0T=k[Tau]0+c and a0ym=k[Tau]m+c, the two formulas are employed to calculate the coefficient k and the coefficient c, and the hyperplane coefficient of any one fault condition ([Tau]1, [Tau]m) is calculated according to the following formula: (img file='DDA0001398374140000011. TIF' wi='286 he='114' / ). The dynamic security region practical and rapid algorithm considering trip time difference of two ends of the line researches the influence on the PDSR (Practical Dynamic Security Region) when the two ends of the line are not tripped at the same to provide a higher requirement for the accurate determination for a security boundary and a stability limit so as to ensure the system security and economy; and moreover, the PDSR solution process is simplified in the error permissible range and the solution time is reduced.

Description

technical field [0001] The invention belongs to the field of safe and stable operation and control of electric power systems, and more specifically relates to a practical fast algorithm for a dynamic safety domain that takes into account the time difference between tripping at both ends of a line. Background technique [0002] Power system faults occur from time to time, and the relay protection device can find out the fault and remove it in time, which is characterized by selectivity, quick action, sensitivity and reliability. In most cases, the fault removal is completed by the main protection. According to statistics, in 2015, there were 138 equipment faults in the 220kV and above voltage level AC system of Hebei Power Grid, and 138 faults were quickly removed by the main protection. 100% rapid fault removal rate [1] . The main protection of 220kV and above lines is longitudinal protection [2] , this paper studies 220kV and above lines, and the fault removal time consi...

AI Technical Summary

Problems solved by technology

In the actual operation of the power system, the action time of the relay protection is a random variable near the set value, and there is a time difference between the tripping actions on both sides of the line. [3]-[7]

When the two ends of the line are not tripped at the same time after the fault is taken into account, how much will the stability limit and safety boundary of the system change? This problem has not been reported so far.

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