CONTROL METHOD AND SYSTEM FOR CONTINUOUS HIGH AND LOW VOLTAGE RIDE THROUGH OF PERMANENT-MAGNET DIRECT-DRIVE WIND-DRIVEN GENERATOR SET

摘要

A control method and system for continuous high and low voltage ride through of a permanent-magnet direct-drive wind-driven generator set. The control method comprises: monitoring the voltage of a grid connection point of a wind farm; determining a transient state time period for a wind-driven generator set to switch from high voltage ride through to low voltage ride through; in the transient state time period, controlling the wind-driven generator set to provide gradually increasing active current to the grid connection point; and in the transient state time period, controlling, according to the working state of the wind-driven generator set before high voltage ride through, the wind-driven generator set to provide reactive current to the grid connection point. Thus, the effective support for the voltage of a power grid is achieved.