Power system stability evaluation method based on multi-feed generalized operating short-circuit ratio

Abstract

A power system stability estimation method based on multi-feed generalized operating short-circuit ratio (GOSCR) is proposed. The method includes: inputting the multi-feed generalized operating short-circuit ratio MIGOSCR model according to the power flow information; judging whether the output value of the MIGOSCR model is 1; If the value is greater than 1, the power system is in a stable state;If the value is equal to 1, the power system is in critical stable state. If the value is less than 1, the power system will lose stability. In accordance with that prior art, the invention solves theproblem that in the engineering planning process of the electric power system, MIESCRi is used as an index to plan the inaccuracy of the voltage support strength of the receiving AC system to the DCsystem, The method of the invention can accurately design the critical strength required by the receiving AC system for the voltage support of the DC system, so that the stability of the power systemcan be ensured, the system resources can not be wasted, and the economy can be ensured.

Description

technical field [0001] The invention relates to on-line monitoring and control of a power system, in particular to a method for judging the stability of a power system based on a multi-infeed generalized operating short-circuit ratio. Background technique [0002] Due to its advantages of low loss and large capacity, high-voltage direct current transmission has become the way of long-distance power transmission in my country. In the normal operation of the power system, as the DC transmission capacity gradually increases, the strength of the AC system at the receiving end becomes relatively weak; when the commutation failure of the DC system causes DC blocking, it will cause the power flow at the sending end to shift, which in turn will lead to Voltage instability occurs at the weak point, that is, the system loses stability. However, a large amount of reactive power needs to be absorbed during the DC recovery process after the fault is removed. If the reactive power compen...

AI Technical Summary

Problems solved by technology

The previous multi-infeed effective short-circuit ratio is an empirical index, which lacks strict theoretical proof, which leads to different critical values ​​in different systems.

According to the empirical critical value 1.5 provided by CIGRE to judge the critical static voltage stability of the system, there will be inaccurate problems

Moreover, the multi-infeed effective short-circuit ratio does not take into account the influence of the DC system control mode on the static voltage stability

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