Expansion of FRT operation range for grid-tied matrix converter system

This paper proposes a control method to expand a fault-ride-through (FRT) operation range for a grid-tied matrix converter. In the conventional method, the generator current is limited because the q-axis current is only controlled whereas the d-axis current is kept to zero. Consequently, the matrix converter cannot satisfy the FRT requirements for the grid reactive current due to the limitation of the generator current. Therefore, in the proposed method, the d-axis current is injected in order to be able to increase the generator current as well as the grid reactive current. This results increase the maximum grid reactive current by 15% as compared to that of the conventional method. From the simulation and experimental results, the proposed method expands the FRT operation range from 43 % to 100%, the FRT operation range is expanded by 57pt.