High-speed doubly-fed unit grid-connection control method and system

Abstract

The invention discloses a grid connection control method and system for a high-speed doubly-fed unit, relating to the technical field of wind turbine grid connection control, comprising acquiring wind turbine unit parameter information and constructing a state variable vector based on state-space modeling. Setting the sliding mode surface function and constructing the sliding mode control law, and processing the sign switching logic in the rotor-side current control by combining the boundary layer function. After the preset criteria conditions for frequency error, phase angle error, and voltage difference are satisfied, triggering the grid connection execution action, and performing closed-loop tracking correction for frequency drift and current harmonics.