Analysis of Sliding Mode Control of variable speed wind turbine system with PMSG

This paper presents the studies of the nonlinear control method of variable speed wind turbine system with Permanent Magnet Synchronous Generator (PMSG). The considered system consists of wind turbine with direct-driven PMSG, the Machine Side Converter (MSC), Grid Side Converter (GSC) and control circuits. The mathematical models of wind turbine system and PMSG have been described. The control algorithms of the converter systems based on the methods of Sliding Mode Control (SMC) have been applied. In the control system of the MSC the Maximum Power Point Tracking (MPPT) algorithm has been used. Additionally the pitch control scheme is included in order to prevent mechanical damage of the wind turbine and to achieve limitation of maximum turbine power. In the control system of GSC the method of Voltage Oriented Control (VOC) has been applied. The considered wind energy system has been studied by digital simulation. The simulation studies showed the effectiveness and robustness of the proposed methods of SMC.