Patent ID: 9722520
Date: 2017-08-01
CPC Classifications: F03D,F05B,H02P,Y02E

Claim:
1. A method for controlling a variable speed wind turbine generator connected to a power converter comprising switches, said generator comprising a stator and a set of terminals connected to said stator and to said switches, said method comprising: determining an estimated stator flux value corresponding to an actual generator power; calculating a stator flux difference value between a stator flux reference value and the estimated stator flux value; calculating a stator flux difference vector with a magnitude and direction, wherein the stator flux difference vector is a difference between a stator flux reference value and an estimated stator flux vector value; and operating said switches of said power converter with switching times based at least on the stator flux reference value, the estimated stator flux value, the calculated stator flux difference value, the stator flux difference vector, and a DC-link voltage of the power converter to adapt at least one stator electrical quantity to obtain a desired generator power magnitude, wherein said switches are operated according to a space vector modulation scheme for controlling a switching pattern of said switches, and wherein said switching pattern is formed by applying one or more vectors during one or more switching times, and said switching times for the switching pattern is determined from the magnitude and direction of the stator flux difference vector.