Matrix converter based wind generation system with low voltage ride through capability

The aim of this work is to propose a strategy to guarantee Low Voltage Ride Through (LVRT) capability of a matrix converter based wind turbine without the need of additional external equipment. The proposed wind generation system is equipped with a Permanent Magnet Synchronous Generator (PMSG) and a Matrix Converter. Under normal operation conditions the Maximum Power Point Tracking (MPPT) is guaranteed by a speed controller that establishes the reference torque and sets the reference currents for the matrix converter. In the occurrence of voltage sags, new reference torques need to be established, to limit the currents in the matrix converter and in the PMSG stator windings. Also, to support the voltage, reactive power needs to be injected in the grid connection point. With this approach it is possible to guarantee that the PMSG is not disconnected from the grid in the presence of voltage sags with a depth of 80% all through 500ms.