Wind power farm tripping method and device for preventing transient voltage instability

Abstract

The invention provides a wind power farm tripping method and device for preventing transient voltage instability. The method comprises steps as follows: acquiring a dynamic grid model, and setting a wind power farm model in the dynamic grid model to be a constant-power source so as to obtain a differential-algebraic equation set of the dynamic grid model; performing time-domain simulation on the differential-algebraic equation set under the condition of preset faults to acquire a singular point for terminating the time-domain simulation; acquiring a partial derivative matrix of the differential-algebraic equation set, and calculating the minimum modulus characteristic value of the partial derivative matrix at the singular point and a corresponding left characteristic vector of the partialderivative matrix at the singular point; determining an active balance equation in the left characteristic vector and an element wk corresponding to the active balance equation; performing tripping onthe wind power farm with the maximum element wk modulus value under the condition of preset fault. Control performance parameters of the wind power farms are acquired by the aid of left characteristic vector information at the singular point, the wind power farm with the best control effect is selected for implementation of tripping emergency control, and stability of a grid system is guaranteedwith the minimum tripping price.

Description

technical field [0001] The invention relates to the technical field of electric power system safety control, in particular to a method and device for preventing transient voltage instability in a wind farm. Background technique [0002] The characteristics of wind turbines are different from traditional synchronous generators. Due to the existence of the internal flux linkage of the synchronous generator, the potential is often expressed in the transient process, and the ability to control the voltage is strong. The ability of wind power to control power of wind turbines is strong, and the power can be quickly and flexibly adjusted through power electronic devices, but the ability to control voltage is weak. Voltage stability is a problem that needs to be paid attention to after large-scale wind power is connected to the grid. When the power grid is disturbed and causes the voltage drop of the grid-connected point of the wind farm, the wind turbines that do not have the vo...

AI Technical Summary

Problems solved by technology

The ability of wind power to control power of wind turbines is strong, and the power can be quickly and flexibly adjusted through power electronic devices, but the ability to control voltage is weak

Images