DFIG subsynchronous oscillation suppression method based on double-second-order generalized integrator

Abstract

The invention discloses a DFIG subsynchronous oscillation suppression method based on a double-second-order generalized integrator, and belongs to the field of doubly-fed wind generator subsynchronousoscillation suppression. The problem that the stability of a power grid is affected due to the fact that subsynchronous oscillation of a DFIG unit of a wind power plant is induced when a series compensation capacitor is added into an existing long-distance power transmission line to improve the electric energy quality is solved. In the control process of the rotor converter, the subsynchronous harmonic component in the stator output voltage Vabc in the process of obtaining the phase theta1 by using the phase-locked loop is filtered by using the phase-locked loop realized by the second-order generalized integrator; a stator current sub-synchronous component suppression ring realized by a quasi-resonance controller is used for generating an estimated value of a sub-synchronous harmonic component in the DFIG rotor side rotor input voltage to counteract the harmonic component in a DFIG rotor side rotor input voltage instruction. The method is mainly used for suppressing the subsynchronousoscillation of the wind power generation system realized by the DFIG.

Description

technical field [0001] The invention belongs to the field of suppressing subsynchronous oscillation of a doubly-fed wind power generator (DFIG). Background technique [0002] The grid-connected penetration rate of new energy power generation has gradually increased, and the grid-connected capacity of wind power has continued to expand. How to improve the grid-connected stability of wind farms and how to improve the stability of the grid are the main issues of the future smart grid. [0003] Usually, wind farms are built in remote areas. Therefore, after the wind energy is converted through electromechanical, a long-distance electric energy transmission is required to output new energy power to the load. In modern power grids, series compensation capacitors are often used in the lines to reduce the influence of inductance effects, thereby improving the power factor of transmission lines. The method of series compensating capacitors tends to cause low-frequency oscillation o...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to solve the problem that adding series compensation capacitors to the existing long-distance power transmission lines to improve the power quality will induce subsynchronous oscillations in the DFIG units of the wind farm and affect the stability of the power grid. DFIG Subsynchronous Oscillation Suppression Method of Integrator

Images