Control method for direct torque controlled PMSG in wind power generation system

This paper proposes a generator control method for a variable-speed wind power generation system using an interior permanent magnet synchronous generator controlled by a direct torque control scheme. The proposed system has neither a wind speed sensor nor a generator position sensor, and is expected to have cost and reliability advantages for small power generation systems. It also offers several advantages over conventional current control systems: (1) ease of maximum power point tracking; (2) ease of flux-weakening control in high speed winds; (3) a novel method of torque limiting, which makes it easy to maintain the armature current at the limiting value. The experimental results demonstrate the effectiveness of the proposed system including its performance at the cut-in wind speed, and also show the influence of parameter variation.